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MID-SCALE EMBEDDED GENERATION CONNECTION STANDARDSFEASIBILITY STUDY FINAL REPORT

Embedded Generator Technical Standards Feasibility

Prepared for The Commonwealth Department of Resources, Energy and Tourism

12 June 2013


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Mid-Scale Embedded Generation Connection Standards


Feasibility Study Final Report

Prepared for

The Commonwealth Department of Resources, Energy and Tourism

Prepared by

AECOM Australia Pty Ltd

Level 2, 60 Marcus Clarke Street, Canberra ACT 2600, Australia

T +61 2 6201 3000 F +61 2 6201 3099 www.aecom.com

ABN 20 093 846 925

24 June 2013

60282416

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© AECOM Australia Pty Ltd (AECOM). All rights reserved.

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Quality Information

Document Mid-Scale Embedded Generation Connection Standards

Ref 60282416

Date 24 June 2013

Prepared by Colin Watson, Mark Lampard and Yili Zhu

Reviewed by Craig Chambers and David Adams

Revision History

Revision Revision

Date Details

Authorised

Name/Position Signature

1 28-Feb-2013 Draft Report David Adams

Director Energy

Advisory

DA

2 28-Mar-2013 Interim Report David Adams

Director Energy

Advisory

DA

3 12-Apr-2013 Interim Report - revision David Adams

Director Energy

Advisory

DA

4 27-May-

2013

Final Report Draft David Adams

Director Energy

Advisory

DA

5 12-Jun-2013 Final Report David Adams

Director Energy

Advisory

DA

6 23-Jun-2013 Final Report - after client

review

David Adams

Director Energy

Advisory


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Table of Contents

Executive Summary i Introduction 1 1.0

1.1 Background 1 1.2 Summary of previous work 2 1.3 Project Scope 2 1.4 AECOM Methodology 2

Australian and International Industry Literature Review 5 2.0

2.1 Scope 5 2.2 Australian Literature 5 2.3 Overseas Literature 9 2.4 Summary 11

Stakeholder Consultation Discussion 12 3.0

3.1 What is unique to mid-scale generation? 12 3.2 What is your organisation’s appetite and requirements for this standard? 13 3.3 What are the embedded generator proponent’s needs that a standard can address? 14 3.4 How can the technical requirements be balanced with financial considerations? 14 3.5 What are the critical requirements for existing customers? 15 3.6 What are the most appropriate scope and level of detail for a connection standard? 15 3.7 Additional comments 15

Commercial Discussion 17 4.0

4.1 Extent of feedback received on commercial aspects 17 4.2 Potential cost impact 17 4.3 Potential response and actions by DNSPs 17 4.4 Potential response and actions by generation proponents 18 4.5 Potential response and actions by generator suppliers/installers 19 4.6 Potential market benefits and risks 20

Considerations for New Technical Standards 21 5.0

5.1 Feasibility of developing technical standards 21 5.2 Single or multiple standards 22 5.3 Range of technical issues 22 5.4 Stakeholder participation 23 5.5 Use of International standards 23 5.6 Experience overseas 24 5.7 Alternatives to a Technical Standard 24

Characteristics of Technical Standards 26 6.0

Summary and Recommendation 27 7.0

Glossary 28 8.0

References 29 9.0

9.1 Australian 29 9.2 International 30

Appendix A List of Stakeholders A

Appendix B B Stakeholder Questionnaire B


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i

Executive Summary

The Department of Resources, Energy and Tourism (RET) has engaged AECOM Australia Pty Ltd (AECOM) on behalf of state, territory and Commonwealth governments to conduct a feasibility study on the development of a grid connection technical standard for mid-scale embedded generators. The purpose of this project is to examine whether it is feasible to develop standards for the connection of mid-scale embedded generation to the electricity distribution networks within Australia that will assist in achieving the objectives set out by RET, being:

To contribute to delivery of Measure 1.1.3 of the National Strategy for Energy Efficiency, to “Maximise

the potential for the application of cogeneration, tri-generation and other distributed generation

technologies that increase energy efficiency”, and

To support action on the findings of the Australian Energy Market Commission (AEMC) that the current

framework for determining minimum technical standards creates an impediment to efficient connection

of embedded generators in the National Electricity Market (NEM).

This study focuses on mid-scale embedded generation that is not covered by AS 4777 and is exempt from

registration in the NEM, generally 30 kW to 5 MW, and connected to a distribution network. It covers all forms of

generation in this range and aims to be technology agnostic. The findings may be applicable to generators that

are larger than 5 MW but are eligible for exemption from registration in the NEM due to limited energy export to

the network.

This Final Report provides AECOM’s findings and recommendations from a literature review, stakeholder

consultations, and a technical and commercial assessment. Stakeholders’ comments to the Interim Report were

considered in preparing this Final Report.

Background

At present there is not a set of consistent technical standards within Australia for the connection of embedded generation between 30 kW and 5 MW. The Australian Energy Market Commission has found through its review (AEMC Review of Demand Side Participation in the National Electricity Market Final Report, November 2009, p. 45) that the current framework for determining minimum technical standards creates an impediment to efficient connection of embedded generators in the NEM. The AEMC has found that “the flexibility afforded in determining minimum technical standards is causing delays and increasing costs for embedded generators.”

The lack of consistent technical requirements and practices for connection of mid-scale embedded generators

are, in AECOM’s opinion, evident in the following aspects of the embedded generation market:

The perceived or material technical barriers and cost barriers to investment and connection of

embedded generators.

The lack of standardisation of embedded generation equipment from manufacturers.

The lack of consistent electrical distribution network design standards and practices across Australia to

accommodate future distributed or embedded generation installations.

This project examines the feasibility of creating a set of nationally consistent technical connection standards to

address these issues and serve the above stated RET objectives.

Methodology

AECOM has conducted research on the current technical requirements associated with generation connection

practices throughout Australia.

Relevant industry literature available on the issues pertaining to connection of embedded generators was

researched and reviewed. This included past reviews and consultations conducted in Australia and overseas that

are relevant to this study. In addition the Distribution Network Services Providers’ (DNSPs) own technical

documents, as publically available on their websites, were reviewed.


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A series of stakeholder consultations have been carried out across Australia. The purpose of the consultations

was to seek the views of stakeholders on the issues relevant to the feasibility of establishing generation

connection technical standards. A questionnaire was developed and circulated to all stakeholders in preparation

for the consultation conferences and for post conference written submissions on the technical specifics. State

governments, DNSPs, industry bodies, manufacturers and embedded generation project proponents were invited

to participate in the consultation. Market institutions were also informed of the study. A stakeholder list is shown in

Attachment A. It is considered that these stakeholders have provided sufficiently broad representation across the

industries that are relevant to this study. AECOM has also considered how the technical standards might impact

on the commercial realities that are facing proponents of embedded generation projects.

Consultation Outcomes

Mid-scale generators, due to their size, have a relatively small impact on overall system security when compared

to large generators that require extensive compliance assessment to ensure safe operation. These small sized

generators are often connected to distribution networks, where a range of issues must be addressed to ensure

safety, system security, reliability and quality of supply to other parties. The solutions to address these issues are

often in the form of network augmentations funded by the proponents, or design and operational requirements

and protocols imposed on the embedded generators as conditions for connection.

An appropriate technical standard would assist both the DNSPs and generator proponents in achieving project

milestones by improving certainty for all parties. Broadly, such a standard may be developed and deployed to

deliver the following outcomes:

to improve consistency of connection requirements for all or each category of connection points across

all Australian electricity distribution networks

to open the opportunity to standardise off-the-shelf products and equipment for embedded generators

to provide clearer understanding of the technical complexity and remove uncertainty for embedded

generation proponents

to reduce the costs of embedded generation and therefore increase demand side participation

to promote consistent distribution network designs across Australian DNSPs, which would improve

consistency of connection requirements in the long term.

There are potentially two approaches to developing a standard to achieve the above objectives. One is to develop

a common set of high level criteria for connection outcomes in terms of public and operational staff safety,

operability, service quality, reliability, and network asset safety and security. However, this approach may be

inherently difficult and ineffective. This is because networks have been designed to service load of various types

and characteristics at specific network locations. The network development standards and operational

philosophies also differ from DNSP to DNSP. The connection requirement to satisfy the standard would be

naturally determined on case by case bases which would lead to little “standardisation”.

The other approach is to define a set of specific common technical requirements that both DNSPs and embedded

generation proponents could apply. This is an outcome driven approach. In principle, if such a standard could be

implemented effectively, it should promote connection consistency and have a positive impact on achieving the

stated objectives. This is the approach that AECOM has investigated in detail in this study.

The latter approach requires appropriative level of prescriptiveness. Connection requirements that are too

prescriptive may limit the opportunity for optimisation and may lead to unnecessary or excessive investment that

could be perceived as ‘gold plating’ of the connection requirements.

For achieving the appropriate level of prescriptiveness, AECOM considers that a single standard with multiple

parts is likely to be required to cover:

Generating units with a nameplate rating of between 30kW and 1 MW

Asynchronous generating units with a nameplate rating of between 1 MW and 5 MW

Synchronous generating units with a nameplate rating of between 1 MW and 5 MW


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The scope of the connection requirements are the same as for larger generators, but with less restrictive

parameters, as some of the requirements for transmission networks are less significant in, or not applicable to,

distribution networks. In many cases the requirements are more impacted by the characteristics of the local

network at the point of connection. Many of these technical limits could be set as a minimum or maximum

requirement in a standard.

However, some technical aspects relating to a local network need to be considered on a case by case basis and

in AECOM’s view cannot be addressed with a set of uniform requirements.

Information and feedback from the consultation process indicates that it is too early to determine whether the

overall cost impact of a standard would be positive, negative or neutral for any anticipated benefits before the

details of the standard are determined. On one hand it would appear that a standard would reduce the costs

associated with the connection process and overall make the connection process easier to navigate. It could also

improve the understanding of the technical risk for investors early in the feasibility process. On the other hand, if a

standard is used to provide a reference point for automatic access for embedded generation projects, costs to the

DNSPs to accommodate new connections are likely to increase. A cost benefit test, however, could be applied

during the development of any standard and be made part of the criteria for the standard development.

Summary and Recommendation

There is significant interest and appetite from all stakeholders who have participated in the consultation process to

develop a standard or suite of standards that covers the technical issues relating to the connection of mid-scale

embedded generation within Australia.

A connection standard that balances the costs and benefits would offer benefits beyond potential improvement in

connection process clarity and certainty, outcome predictability and cost to embedded generator connections. It

could contribute to improving national consistency and promoting common industry practices in distribution

network planning, design and operations. It could also contribute to standardisation of equipment which would

lead to cost reduction in equipment, streamlined installation practices, and operational consistency.

We consider that it is most appropriate that a standard or suite of standards be developed rather than an industry

guideline. The standards should be referenced or enforced by the state and territory technical regulatory bodies.

We consider that broad stakeholder participation in the development of a standard is crucial to its success. This is

due to the standard impacting on not only technical requirements, but also business processes, project risk,

capital cost, and return on investment for multiple parties. There was strong interest shown across the majority of

stakeholders for being involved in the development of a technical guide or standard.

Given the need for a nationally consistent approach we recommend that a Standards Australia based technical

standard should be developed and implemented.


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Introduction 1.0

1.1 Background

The Department of Resources, Energy and Tourism (RET) has engaged AECOM Australia Pty Ltd (AECOM) on

behalf of state, territory and Commonwealth governments to conduct a feasibility study on the development of a

grid connection technical standard for mid-scale embedded generators. The purpose of this project is to examine

whether it is feasible to develop standards for the connection of mid-scale embedded generation to the electricity

distribution networks within Australia that will assist in achieving the objectives set out by RET, being:

To contribute to delivery of Measure 1.1.3 of the National Strategy for Energy Efficiency, to “Maximise

the potential for the application of cogeneration, tri-generation and other distributed generation

technologies that increase energy efficiency”, and

To support action on the findings of the Australian Energy Market Commission (AEMC) that the current

framework for determining minimum technical standards creates an impediment to efficient connection

of embedded generators in the National Electricity Market (NEM).

In the NEM, technical connection requirements are specified in the National Electricity Rules for generators which

are registered with the Australian Energy Market Operator (AEMO). In general, generators above 5 MW capacity

must register with AEMO. For very small generators (up to 30 kW) connected via an inverter, there is an

Australian Standard, AS 4777, to guide connection requirements.

However, there is not a consistent set of technical standards for connection of generators between 30kW and

5 MW across Australia. Some states and territories set out their requirements in local laws and regulations.

Otherwise, technical standards are determined by the network service providers consistent with their obligations

to deliver electricity to their customers safely and securely.

The Australian Energy Market Commission (AEMC) has found through its review of demand side participation

(AEMC Review of Demand Side Participation in the National Electricity Market Final Report, November 2009, p.

45) that the current framework for determining minimum technical standards creates an impediment to efficient

connection of embedded generators in the NEM. The AEMC has found that “the flexibility afforded in determining

minimum technical standards is causing delays and increasing costs for embedded generators.”

The lack of consistent technical requirements and practices for connection of mid-scale embedded generators

are, in AECOM’s opinion, evident in the following aspects of the Embedded Generation (EG) market:

the perceived or material technical barriers and cost barriers to investment and connection of

embedded generators

the lack of standardisation of EG equipment from the manufacturers

the lack of consistent electrical distribution network design standards across Australia to accommodate

future distributed or EG installations.

This project examines the feasibility of creating a set of nationally consistent technical connection standards. Such

standards, if feasible, could be expected to contribute to the reduction of barriers and costs for EG investment.


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1.2 Summary of previous work

In the EG space, several studies and investigations have been carried out over the past decade, looking at

whether the market frameworks support efficient levels of connections. These include:

In 2004, Utility Regulators Forum (URF) recommended a national Code of Practice for Embedded

Generation (CoPEG).

In 2006, CRA International completed a review of NEM arrangements for renewable and distributed

generation.

In 2007, Allen Consulting Group and NERA Economic Consulting completed a review and made

recommendations on the development of national frameworks for electricity distribution, including review

of the draft CoPEG and network connection arrangements.

In 2009, AEMC (AEMC, 2009) presented the “findings, recommendations, and supporting reasoning on

whether there are material barriers to the efficient and effective use of demand-side participation in the

NEM.”

In 2010, AEMC found (Stage 2 Report on Demand-Side Participation in NEM) that “the flexibility

afforded distribution companies in determining minimum technical standards is causing delays and

increasing costs for embedded generators.”

In 2011 Energy Networks Association (ENA) produced a guideline for the preparation of documentation

for connection of embedded generation within distribution networks, which was intended: “for use by

ENA members in preparing their own customised public and internal guidelines for connection of

embedded generation at the distribution level of the network”.

September 2011 ClimateWorks Australia, Seed Advisory and Property Council proposed a Rule change

for connecting embedded generators.

While there have been numerous investigations on both the commercial connection and the technical connection

assessment process, these efforts have not led to a set of consistent requirements and processes for the

connection of EG, which has been seen as a market barrier in these reviews.

1.3 Project Scope

The scope of this project is to explore the feasibility of developing a common set of technical requirements for the

connection of mid-scale embedded generators across all DNSPs, including Western Australia and the Northern

Territory, and to gauge industry support for a common connection standard. The assessment of feasibility is

based upon three factors: desirability, achievability and net benefit.

The scope is limited to technical standards and their feasibility only; it does not extend to a review of the

connection procedures and processes within the DNSPs.

This study focuses on mid-scale embedded generators not covered by AS 4777 and exempt from registration in

the NEM, generally 30 kW to 5 MW. It covers all forms of generation in this range and aims to be technology

agnostic. The findings may be applicable to generators that are larger than 5 MW but are eligible for exemption

from registration in the NEM due to limited energy export to the network.

1.4 AECOM Methodology

The general methodology for addressing the requirements of the project consists of literature review, stakeholder

consultations, technical review and commercial impact review.

1.4.1 Research and Consultation

Research was conducted on the current generation connection practices and technical requirements for

connecting EG for all states in Australia.

Relevant industry literature available on connection of embedded generators was researched and reviewed. This

included past reviews and consultations conducted in Australia and overseas that are relevant to this study.


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3

An industry wide consultation with relevant stakeholders was carried out to gauge stakeholder views on the need

for and feasibility of a technical standard. Consultations were held by teleconference, on a state by state basis, as

it was thought that this would encourage open discussion and debate on the questionnaire, thereby capturing all

major issues. A questionnaire was circulated to all stakeholders to obtain stakeholders’ views of the specific

technical requirements. An interim report was circulated to stakeholders and a number of written responses, as

noted in Appendix A were received. The relevant responses and comments from the stakeholders have been

considered in this final report.

1.4.2 Stakeholder involvement

The following stakeholders have been identified, in conjunction with RET, and engaged in the consultation

process.

market institutions

Distribution Network Service Providers

industry bodies, including organisations representing developers and investors

equipment suppliers identified in consultation with the Clean Energy Council (CEC) and Energy

Efficiency Council (EEC)

A full list of stakeholders is included in Appendix A. AECOM considers that these are the key stakeholders and

represent broad industry players in manufacturing, design, installation, connection and operation of EG as well as

investment in this market.

1.4.3 Technical Review

A range of technical connection issues were considered, including but not limited to:

Power system protection schemes and settings – to ensure correct and safe operation of protective

devices

Equipment fault level contribution and management – ensures equipment and apparatus remains

within design parameters

Network and supply voltage levels – quality of supply to customers is delivered within allowable

tolerance bands

Communications and control – visibility and control of networks to ensure a stable and safe

environment for operators

Operational and public safety – Safety to the public and network operatives

Security of network and supply – ensures that the security of supply remains within planning

requirements

Power quality – quality of supply to customers is delivered within allowable tolerance bands

Availability of generation – ensures sufficient generation to meet load demand.


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1.4.4 The context of the feasibility assessment

The feasibility, that is, desirability, achievability and net benefits of a connection standard, has been considered in

the following context:

What is unique to mid-scale generation that needs to be reviewed?

What is the stakeholders’ appetite and requirements for a standard?

What are the embedded generator proponents’ needs that a standard can address?

How can the technical requirement be balanced with financial considerations from the proponent’s

perspective?

What are the critical requirements to ensure reliability, safety and quality of supply to existing

customers?

What are the most appropriate scope and level of detail for a connection standard?

What level of willingness to engage do stakeholders have?

What are the successes and relevant experiences overseas?

What international standards on embedded generators are available and currently being utilised?

1.4.5 Commercial Impact Review

Our team has analysed the technical findings and has provided a review of how these findings may impact on the

overall process, timing and cost of connection. We have attempted to answer questions such as:

What impacts would a standard have on the cost of connection and the timeframes?

How can the technical and commercial uncertainties facing the generator proponents and property

developers be reduced through a connection standard?

What are the anticipated behaviours, commercial practices and investment decisions that a connection

standard may lead to?

How might a standard impact the commercial viabilities of embedded generators?


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Australian and International Industry Literature Review 2.0

2.1 Scope

The scope of the literature review included desktop research of domestic and international regulations on mid-

scale EG, domestic DNSP connection guidelines, and issues identified in the past public reviews and

consultations in relation to EG connections.

The literature has been reviewed in the context of whether a single or multiple set of standards may be required;

whether a set of minimum or other level of standard could be specified; whether local network characteristics may

affect the requirements; and what may be evident as unique to mid-scale generators. The international literature

has also been reviewed for feasibility of adoption within Australia.

2.2 Australian Literature

2.2.1 Overview

For generators that are registered within the NEM, technical standards for connection and continued compliance

therewith are defined in schedule 5.2 of the NER. The NEM Generation Registration Guide provides a standing

exemption for generating systems with “a nameplate rating of less than 5 MW” as they “cannot significantly affect

market outcomes or impact power system security” (AEMO, 2010). This Guide also confirms that the “conditions

for connection of Generators do not apply to your facility if you are eligible for exemption from registration in

respect of the facility and the facility is connected or intended for use in a manner the Network Service Provider

considers is unlikely to cause a material degradation in the quality of supply to other Network Users” (AEMO,

2010).

However, there are guidelines and electricity codes in each jurisdiction and in many cases the DNSPs still require

compliance with the technical standards and requirements of Schedule 5.2 of the NER, indicating that a level of

standardisation is achievable and possibly desirable from the point of view of DNSPs.

The Northern Territory and Western Australia electricity networks are not governed by the NER and hence each

has its own independent version of technical standards.

Table 1 summarises the high level differences between the publically available DNSP guidelines on the technical

requirements for connection to their network.

The subsequent sections summarise samples of the technical requirements in each jurisdiction gleaned from the

material publically available via the selected DNSPs website. The review is not intended to be exhaustive but

rather only provide an indication of the different regulatory structures and variation in the accessibility and

consistency of documentation across regions and States; and in some instances, even within a region.


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Table 1 Summary of DNSP documentation on mid-scale generator connections

State/NEM

Region

DNSP Guidelines

available?

Complete

technical

criteria

provided?

Separate

guidelines for

non-AS4777

invertor/PV?

Mid-scale

boundary

defined?

New South

Wales

ActewAGL

Ausgrid

Endeavour

Essential Energy

Yes

Yes

Yes

Yes

No

No

No

No

Yes

No

No

No

No

Northern

Territory

Power & Water Technical

Code

No No No

Queensland Energex

Ergon Energy

Yes

No (pending)

No

No

Yes

No

1-5 MW

South

Australia

SA Power Networks Yes No No No

Tasmania Aurora Energy Yes No No No

Victoria CitiPower/Powercor

Jemena

SPAusnet

United Energy

Yes

Vic ESC

Vic ESC

Vic ESC

No

No

No

No

No

No

No

No

2-10 MW

No

No

No

Western

Australia

Horizon Power

Western Power

Yes

Yes

No No

No

1-10 MW

1-10 MW

2.2.2 Queensland NEM Region

Energex provides a customer standard for small to medium scale embedded generation (Energex, 2012), which

incorporates the connection application process, the technical requirements, and the system standards all in the

one document. Minimum standards are provided for many criteria, and provision is made for local network

impacts on quality of supply standards. The technical requirements are similar in scope to the NER but neglect

impacts on system security, which might be interpreted as saying that this is less important for mid-scale

embedded generators.

The main requirements cover:

Generator control systems to manage synchronisation, voltage and reactive control;

Fault level management;

Protection systems and schemes;

Remote monitoring and control;

Earthing requirements;

Power quality.


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2.2.3 New South Wales NEM Region

2.2.3.1 ActewAGL Requirements

ActewAGL makes a distinction between photovoltaic installations up to 200kW, and larger photovoltaic systems,

and synchronous generators with a total nameplate rating not exceeding 5 MW at a single connection point. Their

documentation reflects this division, saying that they outline “ActewAGL’s minimum requirements to ensure these

obligations are met” (see Table 2). Separate guidelines are developed for each group to provide the necessary

focus.

Table 2 ActewAGL’s connection requirements

Generator Requirements

PV up to 200kW AS4777 parts 1 to 3

ActewAGL’s service and installation rules

ActewAGL’s guidelines for the connection of small PV generators in parallel with

ActewAGL’s distribution network.

NER chapter 5

NECF Second Exposure Draft (2009)

PV greater than

200kW

As per smaller units;

ActewAGL’s “Large scale photovoltaic installations”

NER clause S5.2.5.

Small generators up

to 5 MW

ActewAGL’s minimum requirements as per “Guidelines for the connection of small

generators in parallel with the ActewAGL distribution network”, which only refers to the NER

S5 for voltage unbalance.

2.2.3.2 Ausgrid Requirements

Ausgrid separates their connection requirements into several documents. The overall process is communicated in

ES11. The technical requirements are defined in NS194, and the system standards are provided in ENOS. This

parallels the approach within the NER, where schedule 5.1 and schedule 5.1a detail the requirements for system

standards and network performance.

Ausgrid’s (2011) “ES11 requirements for connection of embedded generators” process document defines the

three embedded generator categories. This shows that Ausgrid generator categories align with the mid-scale

category being reviewed in this report, but aggregate bands proposed by ENA (2011).

NS194 (Ausgrid 2008) details the technical requirements for connecting embedded generators in parallel with

Ausgrid’s network. The scope of requirements are similar to the NER S5.2, however, minimum access standards

are proposed for several, which are generally less onerous than for large generators, which is consistent with the

reduced impact expected. Voltage management requirements include that the “preferred operating range is 0.9

lag to 0.95 leading” (p18). The protection services required, for example, are “categorised as Mandatory, Optional,

Recommended and Not Applicable depending on the size of the generating units and the connection of the

network (Ausgrid 2008)”. Provision of a minimum suite of monitoring and control functions are specified.

NS194 generally does not quote specific system standards, but refers the reader to another public document

(Ausgrid, 2011). Within this document, the applicable Australian standards or NER requirements are specified for

the various operating characteristic.


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Table 3 Ausgrid embedded generator categories and technical requirements (AusGrid, 2011)

EG Rating Source Documents

Up to 10kVA for single

phase & 30kVA for three

phase

Ausgrid’s Standard Form Customer Connection Contract (SFCCC)

ES 1 – Customer Connection Information

Service and Installation Rules (SIR)

AS 4777 – Grid connection of energy systems via inverters (if applicable)

Greater than 30kVA but

less than 5MW

To be determined on a case by case basis, it will either be a combination of SFCCC, ES

1, NS 194 and the Service and Installation Rules of NSW or Ausgrid’s standard

Generator Connection Agreement (GCA) with detailed or concise Schedule 2

5MW and above The Rules and the GCA

2.2.4 Victorian NEM Region

CitiPower and Powercor Australia devote a single document to guide HV connected embedded generators, and

typically covers generators between 2 MW and 10 MW. LV connected embedded generator connections are

detailed in (CitiPower, 2012). Those guidelines ultimately define minimum standards but there are several

references to limiting contributions to suit local network capacity.

2.2.5 Tasmanian NEM Region

Aurora Energy provides a single guide to cover the connection process for embedded generators, of size up to

10 MW, and their technical standards. The system standards, however, are provided in the NER and the TEC

clauses 8.6 and 8.7 (Office of TER, 2005).

Minimum requirements are specified for embedded synchronous generators in the TEC clause 8.7.4.

There is little to no reference to system security requirements, similar to other DNSP guidelines.

2.2.6 South Australian NEM Region

The technical requirements for connection to SA Power Networks are provided in ESCOSA (2010), but the

process for connection is provided in SA Power Networks (2012), thus confirming the implementation as a

multiple set of standards. The Electricity Distribution Code (ESCOSA, 2010) provides the standard set of

requirements. System security impacts are generally only reviewed for generator connections greater than 10 MW

unless the transmission network is particularly weak near the distribution connection point.

2.2.7 Northern Territory Non-NEM Region

The electricity network in NT is regulated by the “Network Connection Technical Code” (PowerWater, 2003). This

document defines the technical requirements for both large and smaller embedded generators. The requirements

are ultimately specified to be minimum requirements but in some instances lower capability can be agreed with

the Network Operator.

Performance standards are as per their transmission requirements except where clauses indicate less than

10 MW, and are generally similar to NER schedule 5.1a and 5.2 but specific parameters are likely to be different

e.g. frequency error.

2.2.8 Western Australia Non-NEM Region

Horizon Power is the DNSP for the WA NWIS, RNIS, and Western Power is the DNSP for the WA SWIS.

Western Power’s Technical Requirements for User Facilities within the Technical Rules pertain to embedded

generators with the objective of maintaining the system performance standards to be similar to the NER, but with

subtle differences to the various operating limits. Western Power’s Technical Rules refers to both Australian and

IEC standards.

In the SWIS, “wholesale market participation is compulsory for generation equipment rated 10 MW and above”

(p53, Technical Rules, 2011), and hence doesn’t generally apply to mid-scale EG. Small generators in the SWIS

are defined to be nameplate rating greater than 30 kVA and up to 10 MW and connected to the distribution

system. Generation equipment with a combined rating of less than 10 MW and connected to the distribution

network have a lower set of requirements.


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Separate requirements are provided for energy systems rated up to 30 kVA and connected to the LV system via

inverters. As a result of the distribution role remaining with Horizon Power and Western Power, the technical

requirements are conveniently located within the one document. Separate documents are produced for

distribution connections in general (Horizon Power, 2012) and generator connections up to 10 MW in size

(Western Power, 2008).

2.2.9 Summary of Australian Literature

It can be seen from the sections above that the DNSPs across Australia have developed their own standards and

technical guidelines pertinent to their own particular networks and the idiosyncrasies of their distribution areas.

Most DNSPs have technical guidelines and connection process information readily available on their websites.

They address common issues such as voltage levels, power quality (harmonics, unbalance, and voltage

fluctuations), fault level or fault contribution and dynamic state technical studies. These guidelines differ in

technical specifics that reflect the differences between DNSPs in network design and configuration, operational

philosophies and practices, risk appetite and regulatory environment. DNSPs’ guidelines aim to achieve sound

engineering outcomes for their network taking account of network and business characteristics and costs.

Many of these guidelines state minimum requirements for connection or characteristics of design prior to

connection, usually without any automatic requirements stipulated. It is worth noting that jurisdictional regulations

and industry codes do not set “upper” and “lower” boundaries on what DNSPs can require in their connection

guidelines.

2.3 Overseas Literature

The following international set of standards was reviewed:

IEEE 1547 Standard for Interconnecting Distributed Resources with Electric Power Systems (US)

IEEE 1547a Standard for Interconnecting Distributed Resources with Electric Power Systems –

Amendment 1 in progress (US)

ENA, G59/2-1 Recommendations for the Connection of Generating Plant to the Distribution Systems of

Licensed Distribution Network Operators, 2011 (Australia)

ENTSO-E, “Network Code Requirements for Grid Connection Applicable to all generators – Frequently

asked questions”, 19 June 2012 (Europe)

ENTSO-E, “Network Code Requirements for Grid Connection Applicable to all generators –

Justification Outlines”, 26 June 2012 (Europe)

ENTSO-E, “Network Code Requirements for Grid Connection Applicable to all generators –

Requirements in the context of present practices”, 26 June 2012 (Europe)

ENTSO-E, “ENTSO-E Network Code for Requirements for Grid Connection Applicable to all

Generators”, 8 March 2013SC C6 Distribution systems and dispersed generation (Europe)

SC C6 (global organisation) has published the following Technical Brochures:

- Technical Brochure 271, 2005, “Connection of Generators and other Customers - rules and

practices”, final report of WG C6.02

- Technical Brochure 311, 2007, "Operating dispersed generation with ICT (Information &

Communication Technology)", final report of WG C6.03

- Technical Brochure 313, 2007, "Connection criteria at the distribution network for distributed

generation", final report of TF C6.04.01

- Technical Brochure 423, 2010, "Technical and Commercial Standardisation of DER / microGrid

Components", final report of WG C6.10

- Technical Brochure 450, 2011, "Grid Integration of Wind Generation", ELECTRA, February 2011,

final report of WG C6.08


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- Technical Brochure 457, 2011, "Development and operation of active distribution networks", final

report of WG C6.11

- Technical Brochure 458, 2011, "Electric Energy Storage Systems", final report of WG C6.15

Preliminary review indicated that the experience overseas was similar to that in Australia, with the need to pool

together a large number of independent guidelines and codes. The recent changes in the energy market (e.g.

introduction of policies and incentives to EG investment, as well as cost reductions in some EG technologies) is

leading to increased numbers of embedded generators, hence the requirement for more specific standards being

developed, and the focus on streamlining the process for connection.

The UK standards for distributed generators are divided by size and whether they are inverter based. The UK’s

“ER G59/2 Recommendations for the Connection of Generating Plant to the Distributed Systems of Licensed

Distribution Network Operators” (ENA, 2011) sets out the technical requirements for mid-scale connections. It is

used as the basis for local distribution providers to define their own technical requirement. The actual system

standards are defined in the Distribution Code.

The IEEE 1547 set of standards (IEEE, 2003) for the interconnection of distributed resources with electric power

systems appears to be more successful in being made statutory in the United States, as this standard has been

made national law through the Energy Policy Act of 2005. This set of standards is broken into a number of

volumes which cover specific aspects of connection, including:

Conformance testing procedures;

Application guide;

Guide for monitoring and control;

Draft guide for the design, operation, and integration of distributed resource island systems with electric

power systems;

Draft technical guidelines for interconnection of sources larger than 10 MVA;

Draft guide to conducting distribution impact studies for distributed resource interconnections;

Recommended practice for establishing methods and procedures that provide supplemental support for

implementation strategies for expanded use of IEEE 1547.

Despite IEEE1547 being a single standard and being law, each utility is still required to publish its own criteria and

guidelines, which is similar to the existing situation in Australia where some of the system standards are specified

within the state electricity codes including reference to the NER where required, and connection guidelines fill in

the gaps and link them together.

More applicable to combining standards from many jurisdictions is the work carried out by the European Network

of Transmission System Operators of Electricity (ENTSO-E). ENTSO-E reviewed the technical requirements for

connecting generation throughout the major grids of Europe.

Although targeting transmission networks, the guidelines are structured in chapters to cover technical

requirements and size of generation above 800kW, in decreasing order of impact on system security and

provision of “exhaustive” and “non-exhaustive” requirements. Exhaustive requirements are those that have

parameters explicitly defined, for example frequency deviation ride through and time period for operation. Non-

exhaustive requirements are those that invoke “mere principles”, (ENTSO-E, 2012). As power quality tends to

have only local impact, exhaustive specification of these requirements is omitted from the Network Code.

The structure of the European Network Code (ENTSO-E, 2013) consists of a chapter dedicated to each technical

requirement, for example:

frequency control and fault ride-through;

reactive power capability;

further requirements for synchronous generators – for example, voltage stability;

further requirements for Power Park Modules (solar/wind);

further requirements for Offshore Power Park Modules.


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Each chapter progresses with increasing requirements as the size and voltage of the generator increases –

basically growing the requirements from the previous generator type, for example (refer table 1 of ENTSO-E

2013):

type A generators have greater than 0.8 MW capacity but the connection voltage is less than 110kV;

type B generators have greater than the TSO capacity threshold but less than the limit set in ENTSO’s Network Code for Requirement for Grid Connection (the Code) (by area e.g. Great Britain, Ireland, continental Europe is about 1 MW) and the connection voltage is less than 110kV;

type C generators have greater than the TSO capacity threshold but less than the Code limit (5-50MW) and the connection voltage is less than 110kV;

type D generators have capacity greater than the TSO threshold but less than the Code limit (10-75 MW) and the connection voltage is less than 110kV, or otherwise a connection voltage of 110kV or above.

Clearly Types A, B and C are pertinent to this study and are included within the market rules recognisant of the

increasing impact that large numbers of embedded generators can have on system security. Historically,

embedded generators have been treated as independent and hence having a small to insignificant impact on

system security. However, since system frequency deviations affect all voltage levels at the same time, if large

numbers of embedded generators disconnect from the power system due to protection action, their aggregate

impact may cross regional boundaries.

2.4 Summary

In Europe, the US, UK and across all Australian states and territories, connection standards and guidelines exist

in various forms and with various levels of detail. While the higher level standard provides overarching

requirements, the detailed decisions on each connection requirement still require individual DNSPs to exercise

their own judgement, based on prevailing technical standards such as IEEE or IEC standards, as well as local

network design and operational standards and requirement.

In Australia, these standards, which attempt to address similar technical issues around connection of embedded

generators, have not led to a standardised or nationally consistent set of connection outcomes. These standards

would provide a good basis for developing an Australian national technical standard.


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Stakeholder Consultation Discussion 3.0

An industry wide consultation was carried out across a broad range of stakeholders, as listed in1.4.2, the

response and level of participation from the stakeholders was encouraging with active participation from many

respondents.

The consultation process consisted of two parts: teleconferences and a questionnaire (Appendix B). Six broad

questions, outlined below, were used to obtain stakeholders views. The questionnaire sought more detail on the

technical aspects of embedded generator connections. This section presents the discussions around these

questions.

3.1 What is unique to mid-scale generation?

The intent of this question is to identify potential divisions between different types of generators to establish the

extent to which differences between their connection requirements are due purely to being mid-scale as opposed

to other characteristics of the connection. If the differences in technical requirements are significant between mid-

scale and smaller and larger sizes, then pursuing a separate set of dedicated standards may be worthwhile.

Alternatively, minor changes to the existing NER may be more appropriate.

AECOM’s view is that mid-scale embedded generators are unique in that generally they have negligible impact on

power system security and hence have less stringent requirements on operating characteristics and protection,

remote control and monitoring capability, but are more prone to fault level limitations and power quality issues at

the connection point.

The literature and particularly the DNSP connection guidelines indicated that generally connection guidelines

referred to similar requirements to the NER S5.2, but differed with aspects specific to the network characteristics

at the connection point. NER clause S5.2.5 provided some partial and full exemptions to synchronous and

asynchronous generators below 30 MW in size to comply with certain technical requirements. The requirements

did differ slightly for synchronous generators compared to asynchronous. In the DNSP guidelines there was some

distinction in the requirements for EG less than 1 MW and those greater than this, although in one instance the

threshold was at 4 MW.

A table was developed for this section of the questionnaire, which lists most of the known categories of technical

requirements for larger mid-scale, smaller mid-scale, and smaller generators, and seeks feedback from the

stakeholders as to whether that requirement is unique to the generator’s size, whether it is synchronous or

asynchronous, the voltage of connection, or point of common coupling. The table also attempts to establish

whether each of these items is required with the connection application, or whether this should be only on a case-

by-case basis. A further distinction is made between whether the stakeholder believes that the items should be

included in the technical standard at all, and whether specific details should also be specified. Stakeholders were

requested to place a tick or a cross in the box if that uniqueness statement applied to that item.

Four stakeholders completed this table, which was disappointingly few. However useful feedback on these

technical specifics was gained during the teleconferences, from the few returned questionnaires and from the

feedback to the Interim Report. This indicates that stakeholders preferred the teleconference/meeting approach

rather than written correspondence and this approach should be used for the development of the standard.

Stakeholder Views from the Consultations

The responses indicated that many aspects of the following requirement categories should be included in a

technical standard:

Protection

Reactive power capability

Power quality

Response to frequency and voltage disturbances

Voltage regulation

Remote monitoring and communications

Safety.


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Given the diverse nature of the distribution networks across Australia, there is a number of consistent issues

under the above categories which stakeholders indicated are required to be reviewed on a case-by-case basis,

including:

Protection related:

o pole-slip

o breaker fail

o inter-trip

Reactive power, voltage control and regulation

Power system stabilisers

Remote monitoring, communications and metering

Safety related:

o impedance earthing

o auxiliary supplies via a different Point of Common Coupling (PCC)

o interlocking

Requirements unique to mid-scale embedded generators compared to smaller non-mid-scale generators

included:

Protection related:

o Redundancy

o Main and backup

o Breaker fail

o Inter-trip

o Impact on protection settings near the PCC

Response to disturbances:

o Fault level contribution and clearance times

o Breaker fail

o Delivery of active power and the ability to supply or absorb reactive power, including

maintenance of PCC voltage level.

Impact on network capability

3.2 What is your organisation’s appetite and requirements for this

standard?

AECOM sought to understand the stakeholder’s views and appetite for participation in the process of developing a

technical standard, and this was ascertained in the questionnaire and obtained through the teleconferences.

The benefits to developing the standard were elaborated with the aim of developing a consistent approach across

all DNSPs, and early stage identification of technical requirements for projects to ensure that the connection

process is completed within a reasonable timescale.

Many of the DNSPs pointed out that their technical standards are readily available on their respective websites.

Many DNSPs were still concerned about whether a standard might be able to address all concerns of generation

connection, so that there could still be a portion of work that is particular to where a project is to be connected on

the network, requiring that some projects be considered on a case by case basis.

All participants on the teleconferences were asked whether their organisation was interested in being involved in

the development of a standard. All stakeholders answered positively. Further responses to the Interim Report also

indicated that organisations are prepared to be involved in the development of a standard. This shows strong

interest across the majority of stakeholders for being involved in the development of a technical guide, or standard

detailing the requirements for connecting mid-scale generation.

Any development of a standard would need to be well funded to ensure active participation by a wide group of

stakeholders and to ensure that the requirements of all stakeholders are taken into account.


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3.3 What are the embedded generator proponent’s needs that a standard

can address?

Many developers of generation projects, whether co-gen, tri-gen or explicitly export, are frustrated by the time

taken for the whole connection process. This is often seen as an inhibitor to projects being developed, since it

may be too costly for small or medium enterprises to commence projects due to the costs and uncertainty

involved in engaging in-house or specialist engineering advisors to manage the process.

Some stakeholders consider that, although any standard developed should not cover the connection process, the

common requirements of a technical standard across the many jurisdictions could provide an early indication of

the requirements of technical studies or equipment associated with generation. To achieve this effect, the

standard should assist proponents in understanding the requirements and the order in which technical studies

could be completed earlier in the process and therefore speed up the connection process.

Stakeholders consider that a common set of standards will negate the need to ‘hunt’ for standards associated with

each of the DNSPs, and will increase objectivity.

In regard to economic efficiency, stakeholders consider that a standard would need to provide a more

economically efficient outcome. Therefore, the technical requirements should be no more onerous (either

technically or financially) than is necessary.

The need for consistency in connection requirements across the DNSPs was a key message from many

participants.

Stakeholders consider that one standard could not and should not cover all obligations. This is because many

existing standards applicable to electrical infrastructure already cover not only performance standards but

installation and supplier standards, wiring rules etc. A generator developer needs to be cognisant of all applicable

standards and obligations.

3.4 How can the technical requirements be balanced with financial

considerations?

The number of applications for EG projects varies widely across the DNSPs within Australia. Some DNSPs have

few applications and even fewer that progress to actual projects for construction. Others have many connection

applications that usually progress to construction and commissioning. This suggests that a common standard may

represent different value for individual DNSPs. It was clear from the consultation that the greatest density of

applications was in the various CBDs within capital cities.

Some stakeholders consider that the lack of visibility of network constraints potentially limits Demand Side

Participation (DSP) to achieve maximum efficiency of network in a more intuitive manner to counteract

augmentations by the DNSPs. Although this does not affect the EG connection cost side of the equation, it has

implication on the benefit side. The recent Distribution Network Planning and Expansion Rule change is expected

to increase the visibility of network limits. This rule change stipulates that DNSPs are to provide this information

within their yearly network planning reports.

Many of the stakeholders cited experience relating to individual specific projects where the connection

requirements for EG projects were still considered on a case by case basis even where DNSP’s connection

guidelines already exist.

Stakeholders consider that the provision of minimum technical requirements would mean that many proponents

would be able to understand the requirements earlier in the process.

The complexity and therefore the cost of projects is dependent on many factors including, but not limited to:

magnitude of generation, connection voltage level, location of connection, fault level at connection point and

export capability; these all impact on the DNSP requirements for connection. Several examples were provided

and discussed such as inter-trip/signalling and protection.

An early understanding of the technical issues and requirements associated with connecting would alleviate

frustrations and delays in the full connection process, thereby allowing shorter timescales for connection and

earlier realisation of the financial benefits of EG. It may also encourage small to medium business to investigate

the benefits of EG.


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3.5 What are the critical requirements for existing customers?

According to the current technical regulations, the DNSPs obligations are to its existing customers and to ensure

a safe and reliable network for the public and its own personnel. Connection of new customers, whether load or

generation, should not cause a detriment in electricity supply to existing customers. A customer’s obligations are

documented within their connection agreement, which is reflective of the relative grid, distribution or jurisdictional

rules. These regulatory arrangements mean that DNSPs are solely responsible for ensuring that connections of

new EGs do not result in excessive impact on power supply quality and reliability to existing customers.

Although a customer must ensure that their installation is managed in accordance with their connection

agreement, feedback from consultations indicates that DNSPs generally do not witness or validate assurances by

the customer to adhere to quality of supply, protection or operation arrangements prescribed in the connection

agreements. Some DNSPs are satisfied with completion certificates issued by a suitably qualified engineer.

3.6 What are the most appropriate scope and level of detail for a

connection standard?

The majority of stakeholders suggested that the development of a set of standards should be applicable across

Australia, not just the NEM area. A range of views were expressed with regard to the appropriate scope and level

of details for a connection standard including:

A series of standards should be developed for specific sizes of EG, for example, less than 1MW, less

than 5MW etc.

Whatever standard is developed, it should not only cover the technical parameters of a generator

connection but also information requirements associated with the connection process.

The level of detail within the standards should be limited to include only minimalist requirements or high-

level functional specifications.

The developed standards should be consistent across existing standards and rules such as AS3000,

AS61000.

In relation to the NER, there was a view that the NER could include mid-scale generation, rather than the

current exemption, or the NER could reference a standard, or series of standards, that are applicable to

mid-scale generation.

3.7 Additional comments

The stakeholders provided commentary in addition to their responses to the questionnaire, which are summarised

below.

It was re-iterated that early engagement between proponents and the DNSPs is paramount to the

identification of fatal flaws and the technical requirements for the connection. Agreeing and overcoming

any issues early would ensure a more timely connection agreement and project.

Many projects are driven by proponents who may have little previous experience in doing an EG

project. Therefore, the engagement of suitable engineering resources is paramount to the success of

any project.

Many of the DNSPs publish technical requirements, guidelines and process documents on their

websites, and proponents are encouraged to read these before initial engagement.

Some DNSPs see the development of standards as a way to assist them in developing common

strategies to combat key issues relating to EG connections, for example management of fault levels.

Standards should be developed neutral to technology – functional specifications rather than detailed

requirements are one way to address this issue.

Whatever standard is developed, this should not only cover the technical parameters of a generator

connection but also information requirements associated with the connection process.


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Any standard developed needs to be forward looking as the collective impact of EG and renewable

energy sources on Australian networks are growing.

Any standard development process should have broad participation of, and consultation with,

stakeholders to ensure balanced outcomes with broad support from the stakeholders.


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Commercial Discussion 4.0

This section discusses the possible commercial impact of developing a standard for EG within Australia.

4.1 Extent of feedback received on commercial aspects

As discussed earlier, the consultation process covered a broad range of stakeholders. The consultation process

asked specifically about the pricing and commercial aspects of a standard and how they could be linked. The

feedback received on the commercial requirements was quite varied both with the various DNSPs and within the

proponent and manufacturer groups. There were, however, a number of common threads throughout the

consultations and these are further developed here.

4.2 Potential cost impact

From the consultation process and discussions with stakeholders, it is difficult to determine if the overall cost

impact of a standard would be positive, negative or neutral before the details of the standard are further

developed. On one hand it would appear that a standard would reduce the costs associated with the connection

process and overall make the connection process easier to navigate. On the other hand is the question of costs to

the DNSPs for upgrades required to meet obligations imposed on networks by a standard itself, or through use of

the standard as a benchmark to provide an automatic access right.

It is clear that the time and therefore cost required for the connection process will be reduced with the addition of

a technical standard to the EG connection process. This would be driven by:

An increase in the understanding of DNSP requirements by the proponent as they will be standardised

Increased availability of information from the generator suppliers as the required information will be

standardised

Reduced time to complete analysis as the approach would be standardised

Standardisation of the network options required for the connection of EG projects could reduce costs

for some projects in some locations

Possibly reduced contractual costs as a standardised connection contract may be able to be

established containing the technical standards.

While there is a consensus that standardisation may reduce cost to developers, it is not clear how standardisation

may increase the costs with respect to the requirements that are placed on the DNSPs, especially with respect to

possible network upgrade requirements. This is explored in more detail in section 4.3.1.

Overall the improvements in process associated with the standardisation of technical requirements should reduce

overall costs of connecting EG to networks.

4.3 Potential response and actions by DNSPs

As noted earlier, the consultation process was well attended by representatives of all the DNSPs across Australia.

A number of resulting themes are further discussed here.

4.3.1 Network ability to comply with a standard

During all the consultations there was discussion associated with the ability of the networks to comply with a new

standard and how the DNSPs may need to review their planning requirements and therefore the costs of doing

business. There was a general consensus that, if a standard was to be introduced, there would be a need for

project specific network upgrades to be able to cope with a new standard. This understanding was linked to the

expectation that a standard could contemplate an automatic level of access, similar to the current NER

requirements for larger generators and the ClimateWorks Australia, Seed Advisory and Property Council of

Australia rule change currently before the AEMC.


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How network upgrades that are triggered by proposed EG projects would be financed is worth consideration. The

current situation is that the proponent pays the required costs to upgrade the network at their specific location.

However, it was thought that, with the development of a standard, this funding model may change with a

requirement for automatic access. It is anticipated that the current situation would remain where industry

regulators do not tend to allow retrospective upgrades, due to a change in standards.

It is conceivable that the DNSPs would look to include any works required to achieve compliance with a new

standard in their regulatory submissions. However, recent indications from the energy regulators, including the

2010 distribution determination by the AER, are that this would not be acceptable as it would transfer the costs of

the upgrades for a specific project to all users of the network, which would not contribute to the National Electricity

Objective. It is more likely that the development of the standard would need to take into account the currently

required network standards that DNSPs already need to comply with.

One alternative option considered by AECOM for the funding of network augmentations associated with the

connection of EG could be the use of avoided Transmission Use of System (TUoS) charges. TUoS charges are

charged to the DNSP for their use of the Transmission network and any savings made by the DNSP due to EG

are called avoided TUoS charges. These charges are currently passed to the proponent of the EG project by the

DNSP as they represent the benefit that the DNSP gains from having the EG connected within their network. It

may be possible to utilise these payments over the long term to fund the networks upgrades required for specific

projects.

Generally, a reduction in the connection requirements for EG may lead to an increase in the requirement for

network capability. For example, a relaxation on EG fault level contribution limits may require the networks to

have a tolerance to higher fault levels, or a reduction in monitoring and control requirement on EG installations

may lead to additional monitoring and control requirement on the network side. Even if a standard does not lead

to an automatic access right, project specific network upgrades are likely to be required at a location where a

requirement in the standard is set higher than what the existing networks can provide at that location.

4.3.2 Standardisation of network requirements

It was noted during the discussions that some of the existing network requirements for the connection of EG are

not standard across the DNSPs. One example of this is the need for inter-tripping communication between the

network and the embedded generator. This communication system can be quite expensive for projects that are a

significant distance from the local zone substation and the level of generation where this is required varies for

different networks. Standardising the level of generation and the maximum distance from the nearest zone

substation where this type of system becomes required would provide certainty to EG proponents and, if set at an

appropriate level, could reduce the costs for projects.

The standardisation of expensive connection requirements could be possible through the development of a

technical standard and would give both proponents and DNSPs certainty on the requirements for these items. The

development of a standard could lead to the DNSPs accepting a standard approach and thus reduce the costs

associated with these more expensive network requirements.

4.3.3 Possible standardisation of Connection Agreements

One of the key costs associated with the connection of EG to networks is the time, effort and costs required in

finalising the connection agreement. This is driven by the lack of standard documents and the requirement for the

development of bespoke connection agreements for each connection. It was suggested during the consultations

that the development of a technical standard could encourage the DNSPs to also develop standard contract

documents for EG connection. This would improve the overall time taken to complete the connection process

even further. Although this is not specifically in the scope of this review, it is included here for completeness.

4.4 Potential response and actions by generation proponents

Through the consultations with specific developers, the Property Council of Australia, the Energy Efficiency

Council (EEC) and the Clean Energy Council (CEC), we have seen a positive response with respect to the

concept of having a technical standard for EG. It would be anticipated that the benefits associated with a standard

technical requirements document would increase the number of EG projects being developed.


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A standardised set of requirements would give an improved understanding of the risk associated with the

connection of EG in all jurisdictions. The costs to investors, particularly in the buildings sector, are greater as they

move through the project cycle. An increased understanding of the risk and technical requirements for EG earlier

in a project, would give investors the chance to make more informed decisions concerning EG. This is preferable

to completing a non-standardised connection process where the costs are unknown and could make a project

unviable. During the consultations, the risk of cost overruns late in the connection process due to unforseen

network issues was raised. This risk could be partially mitigated by the development of a connection standard that

sets out the requirements of the project early in the process.

As in all commercial dealings, increased certainty is a positive for investors and increases the chance of them

investing in a project. If there was an opportunity to include certainty in the costs and the allocation of these costs

to the parties within the process, then this could further enhance the benefits case for development of a

connection standard.

One of the potential risks of concern to this group of stakeholders is the possible imbalance of technical

requirements versus capital cost in any technical standard developed. It was highlighted that, if the level of

technical requirement for EG proponents was set too high in a standard, then this could lead to a more capital

intensive approach to projects that may have the opposite effect to that noted earlier. If the technical standard is

too onerous to comply with, projects may become too expensive and reduce the likelihood of investors being

drawn to the sector. To ensure that this risk is managed, a broad participation across the range of stakeholders

involved in this sector should be considered in the development of the standard.

4.5 Potential response and actions by generator suppliers/installers

Both equipment suppliers and installers were included in the consultation. In most cases it is the installer, not the

supplier, that needs to achieve a connection with the DNSP and as such the suppliers have a level of insulation

from the process.

During the consultation with these parties it was noted that the development of any standard should encourage

transparency in the process and conformity of requirements across Australia possibly through the centralisation of

certifications for EG equipment. During the project two key issues were discussed: the information to be shared

with the DNSP; and the centralisation of the technical requirements and process.

4.5.1 Information Requirements

The flow of information required for the connection of EG is bi-directional with information required by the

suppliers/installers from the DNSP and information required by the DNSP from the suppliers/installers. The

information requirements of the various DNSPs within the Australian market are quite varied and as such can

cause confusion during the connection of EG into Australian networks. Having certainty in the level of information

that is to be supplied by the DNSP and the level of information that they will require is seen as a positive for the

suppliers in this market.

Information packages could be developed to cover DNSPs’ information requirements to inform the suppliers of the

Australian market. This would streamline the flow of information for the installers who are leading the connection

process with the DNSP and also provide the DNSP with certainty on the information they are going to receive.

The streamlining of the information flow should provide a time and cost saving in the process of developing an EG

connection.

The technical standard should also provide for standard information flow from the DNSP to the proponent, which

could decrease the time required for completion of the process.

4.5.2 Centralisation of requirements and process

An additional issue raised during the consultation with the suppliers/installers was that the centralisation of the

requirements through a standard is a key to reducing the variability in the requirements across Australia. A

centralised system could see the development of standard certification requirements that could then be used for

connecting EG to all Australian networks. This would reduce the time taken within the process and provide

certifications, similar to current small scale inverter certification, that would give all parties the understanding and

knowledge of what is required.


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One of the risks that could possibly arise from this approach is that suppliers may not want to comply with a

certification process for a small market like Australia. However this is considered a low risk as most international

suppliers are used to having multiple certification requirements. Any development of a certification process would

need to review any processes that may currently be in use in larger EG markets like Germany and USA to ensure

that the Australian requirements are not too dissimilar to those in other markets.

4.6 Potential market benefits and risks

The consultation process suggests that commercial market benefits would flow from the development of an EG

technical standard. For the EG market these benefits will be in the form of:

A well-defined set of technical requirements that the generator suppliers will become accustomed to

achieving. It is anticipated that this could lead to standard data packages and technical solutions being

developed for the Australian market. This could possibly be included in some form of equipment

certification.

Reduced connection process time through all parties understanding the requirements and how to fulfil

them. However, this may lead to the proponent having to increase the amount of work required upfront

of the process.

More timely understanding of a project’s feasibility for financiers due to the technical requirements

being known at an earlier stage. This should lower the technical risk for the project and allow financiers

to make more informed decisions on the inclusion of EG in projects. This should increase the number

of projects being constructed.

Decreased costs and time associated with finalising the connection process and reduce overall project

costs, if the DNSPs were to move to standard connection documentation.

From the review process there are a number of commercial risks that need to be highlighted, as follow:

If a technical standard is to place requirements on the DNSPs that lead to additional project specific

network augmentation costs, there is a low risk that the DNSPs could pass the costs of complying with

this standard through to consumers via adjustments to allowed regulated revenue. The costing

methodology for upgrades needs to be understood as part of the further development of a technical

standard.

The development of the technical standard will need to balance the technical requirements with the

capital cost of achieving these requirements. There is a risk that, if this balance is not achieved, then

the technical requirements could increase the cost of EG projects to such a level that they become

unviable, therefore diminishing potential economic gains.

The development of any technical standard should be cognisant of the size of the Australian market

compared to other markets around the world. Although it is anticipated that there would be standard

documents developed by the equipment suppliers for the Australian market to suit a technical standard,

the suppliers are not likely to put large amounts of effort into establishing conformance to Australian

technical requirements given its size compared to the larger markets in Europe and the USA.


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21

Considerations for New Technical Standards 5.0

This section presents AECOM’s assessment of the feasibility question and relevant considerations for

development of a new Australian standard on EG connection. In Section 5.1 below AECOM has recommended

that the technical standard for EG be developed under the Standards Australia process. This recommendation is

based on the following:

1) One of the key requirements for any new technical standard is the need for it to be nationally consistent.

Standards Australia is the only body that can develop a technical standard that fulfils this requirement.

2) The Standards Australia development methodology and process is able to engage multiple industry focus

groups or stakeholders which is a key part of ensuring broad stakeholder participation in the development of

the technical standard. This is one of our recommendations in this report.

3) An Australian Standard could be utilised as the baseline document that will prescribe the common approach

and understanding of technical requirements for the connection of EG, as per the current series of standards

for line design used by DNSPs.

4) DNSPs will be able to interpret the Australian Standard for use within their own networks, allowing for any

location specific issues to be addressed.

5) The use of Australian Standards to set a national standard is considered to be standard industry practice

across various industries within Australia.

5.1 Feasibility of developing technical standards

The question of feasibility is at the centre of this study. The assessment is based upon three factors: desirability,

achievability and net benefit. AECOM considers that it is feasible to develop technical standards for mid-scale EG

connecting to distribution networks in Australia for the following reasons:

The majority of stakeholders recognised the need for a technical standard and support its development.

There is a strong willingness across the diverse range of stakeholders to improve consistency, clarity

and certainty in EG connection requirements across Australia.

While technical requirements differ in detail among the DNSPs, the fundamental technical

considerations, principles and objectives are similar, which is reflected in the similarity of current

DNSPs’ guidelines or standards for EG connection. There is sufficient consensus among stakeholders

that a range of technical requirements and connection parameters could be standardised.

While there are location-specific connection requirements that cannot be prescribed in a standard, a

methodology and set of assessment criteria can be developed and prescribed in a standard to ensure

predictable and consistent assessment outcomes.

There is a clear expectation among the stakeholders that, while a connection standard would not be an

all-encompassing solution, it would drive and contribute to national consistency in EG connections.

While there are uncertainties in regard to the balance of immediate cost and benefits, which is a

function of how stakeholders may respond to a new connection standard, there is a range of clear

immediate and flow-on benefits that a well-developed connection standard could offer.

The benefit of an EG connection standard would go beyond contributing to improved certainty and cost

of connection activities. It would promote standardisation of EG products and consistency in future

electrical network planning, design and operations in regard to EG.

With the requirement for the technical standard to be consistent nationally, AECOM considers the most feasible

vehicle for the development of a standard to be the Standards Australia process, although other options are

considered further in Section 5.7.


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22

5.2 Single or multiple standards

It appears feasible to develop a single standard, which contains parts for different capacities as per NER schedule

S5.2.5. A single standard has a number of advantages over a set of multiple standards, namely:

Simple to follow

Avoids confusion and a complex standard structure

Easy to maintain internal consistency across sub-classifications

Single reference for common requirements across the sub-classifications.

DNSP guidelines generally only make the distinction between synchronous and asynchronous generators, and

units less than or equal to 1 MW and those greater than 1 MW. From those guidelines, sub-classifications likely to

be required are:

30kW – 1 MW;

Synchronous 1 MW – 5 MW;

Asynchronous 1 MW – 5 MW.

The requirements could reflect the methodology for larger generators as set out in the NER, but with a reduced

requirement on functionality. There would be a need to pay more attention to the impact of the characteristics of

the local network at the point of connection.

5.3 Range of technical issues

The range of technical issues which would be expected to be covered in a standard are proposed to mirror those

covered by NER Schedule 5.2 and tailored for relevance of each sub-classification of EG. These are:

Application of settings – The protection and control settings applied should only be those that have

been agreed with the connecting DNSP.

Technical matters to be coordinated including, but not limited to, the following:

- Protection and control settings including fault level co-ordination and fault clearance times

- Metering

- Interlocking and isolation

- Switching and Operational arrangements

- Plant capabilities and conformance to Australian Standards.

Provision of information – Both the proponent and the DNSP must provide information requested by

either party in a timely manner so as to not delay the progress of the connection application and

construction of the facility. The level of detail and information required must be agreed at the earliest

possible time.

Technical requirement – Content of the technical information is likely to consist of the following data

and allocation of limits by the DNSP:

- Fault current – Fault current contribution from generators will increase the system fault levels

which may impact on the rating of switchgear and apparatus that is owned by the DNSP or the

proponent.

- Voltage fluctuation limits - The impact on voltage fluctuation is a function of the size of the

generator, its operation pattern, adjacent customer’s tolerance to voltage fluctuations, and the

characteristics of the network near the connection point, in particular the source impedance.

While it is not practical to prescribe a limit to a proposed EG, the approach to determining the

fluctuation limit prescribed in other relevant AS standard can be referenced in the connection

standard to improve clarity and consistency.


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23

- Voltage unbalance limits - The impact on voltage unbalance is a function of the ratio of negative

phase sequence to positive phase sequence that is produced due to unbalance loading of single

phase equipment across three phase systems. While it is not practical to prescribe a limit to a

proposed EG, the approach to determine voltage unbalance limits prescribed in other relevant AS

standard can be referenced in the connection standard to improve clarity and consistency.

- Harmonic distortion limits - The impact on harmonic distortion is a function of the size of the

harmonic emissions from the non-linear devices within the generator facility and the harmonic

distortion pre-existing on the network. While it is not practical to prescribe a limit to a proposed

EG, the approach to determine harmonic distortion limits prescribed in other relevant AS standard

can be referenced in the connection standard to improve clarity and consistency.

- Reactive support capability for connections – Depending on the characteristics of the generators

(Synchronous versus Asynchronous) additional reactive support to assist starting and to maintain

voltage at the connection point may be required. This has an impact on the system network that

needs to be incorporated into the design of the connection.

Monitoring and control requirements – Typical monitoring requirements for less than 5MW generation

may include the following:

- Circuit breaker status

- Operating status of Generating units

- Volts / Amps / Watts / Vars

The development of these requirements should also take into account the requirements for similar

sized loads that have similar network issues to generators and rarely have any DNSP monitoring. A

contact point for a responsible person should be made available by the generator for operational

activities.

5.4 Stakeholder participation

Many stakeholders have expressed a desire to support and participate in the development of standards for mid-

scale EG. This desire was stated directly during the consultation discussions and also in several responses to the

Interim Report.

To achieve a standard that balances the stated objective with the interests of all parties, and leads to the overall

most economic outcomes in EG and demand side participation, it is important that during the development of this

standard there is broad participation across the range of stakeholders including governments, market institutions,

DNSPs, EG developers, industry bodies and manufacturers. A number of the groups required to be involved in

the development of a standard operate within small to medium sized commercial businesses and may require

support to be involved in the development of a standard. Therefore the development of the standard needs to be

well funded so that the interests and needs of all sectors of the EG market are adequately presented.

5.5 Use of International standards

Overseas standards would be appropriate for use in Australia except that they would have parameters unique to

the local networks from which they were tuned. Such differences are similar to those demonstrated to exist

between the guidelines for Australian DNSPs; NEM frequency limits and deviations compared to the SWIS, for

example. Overseas standards address similar technical requirements to those covered in Australia and provide a

similar depth as some of the more detailed guidelines from Australian DNSPs. The division within mid-scale

generators that tend to require inter-tripping and additional protection and enhanced performance capability may

also need to be adjusted. This practice of providing a single threshold for mid-scale, and several thresholds for

large generators, is replicated within ENTSO-E (2013), but the actual thresholds may need to be reviewed as the

parameters for this and other exhaustive requirements have been tuned through the history of these networks.


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24

Whether an international standard is converted or an existing Australian structure for the mid-scale embedded

generator technical requirements is adopted, during the transition to unified requirements there would need to be

some mapping which delineates the requirements in each local network by either the NEM region or non-region,

or the DNSP. As further investigation is conducted to resolve those differences, the mapping table can be

simplified and eventually removed when complete.

Another area where international standards may prove useful is their demonstration of different structures for the

technical requirements. The ENTSO-E Network Code (2013) presents an alternative hierarchical structure which

could be adopted within an Australian standard to incorporate all generator sizes above some minimum threshold.

The IEEE model implements multiple volumes but is also one standard.

5.6 Experience overseas

Experiences overseas have shown variable levels of success in standardisation of connection requirements.

These overseas experiences and approaches provide useful reference in developing the Australian standard. For

example, European experience with ENTSO-E has demonstrated that many of the technical issues are pertinent

to either distribution or transmission networks and can be allocated to their respective rules accordingly. The

network wide issues and locality dependent issues can be separated and dealt with through different approaches.

The USA’s development and application of IEEE 1547 also demonstrates how a national standard and individual

DNSPs’ guidelines can work together.

These experiences should be closely examined as lessons can be drawn in the development and implementation

of an Australian standard.

5.7 Alternatives to a Technical Standard

There are other options available for consideration, although the Standards Australia based technical standard is

the preferred approach to promote national consistency and reduce impediments to wider demand side

participation.

5.7.1 Implementing a Rule change to the NER:

Examples of this approach are:

Insertion to Schedule S5.2.5 through S5.2.8

Addition of a schedule to chapter 5

Addition of a chapter akin to chapter 5A.

The NER rule change alternative is expected to require the same amount of rigour as would be required to

develop a technical standard, but it would require no extra effort to implement. However the NER approach does

not lead to 100% coverage in Australia. As NT and WA are outside of the NEM and often have smaller remote

power stations that supply islanded networks, this approach would not ensure nationally consistent outcomes

unless an additional arrangement is developed to ensure consistency.

A technical standard however, does not become law unless compliance with its requirements is defined within

either the Electricity Acts or equivalent in each State, or an enabling authority such as the NER. Hence this extra

step and cost would be required for implementation.

The majority of proponents involved with mid-scale generation are typically less informed and have greater

difficulty interpreting what is required to comply with the DNSP’s connection requirements. It may be that

development of a technical standard is only half of the equation and additional resources might need to be

standardised to avoid replication and customised guides being developed by each DNSP.


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25

5.7.2 Creating industry guidelines

Examples of this approach are:

Single industry guidelines for the Electricity Supply Industry, which other industries voluntarily apply

Multiple industry guidelines that are developed in a coordinated fashion

Industry guidelines are an effective instrument to promote common practices and outcomes. In the electricity industry it would be considered the norm for new industry requirements to commence as an industry standard. One example of this is the line construction guideline developed by Energy Networks Association (ENA) that has since been converted to an Australian Standard. However this approach is usually only used within a single industry or industry body.

The EG connection requirement is across multiple industries and as such may be harder to implement using this

approach. It may be possible to discuss with a single industry body, for example the ENA, the concept of creating

an industry guideline in conjunction with the other interested parties, like the Energy Efficiency Council (EEC) and

Clean Energy Council (CEC).

5.7.3 Mixture of approaches

One example of a mixed approach could be:

Utilising the NER for high level requirements

Develop a technical standard for only a few specific EG requirements

Local DNSP guidelines for custom requirements.

The combination of NER and technical standard would offer additional benefits such as improvement in the

alignment of objectives and effectiveness in DSP and EG. Those technical requirements that have system wide

impacts could be included in the NER, i.e. frequency and voltage fault ride through and capability; and those that

don’t have system wide impact could be covered by a technical standard and local DNSP guidelines. Similar to

the NER approach, additional arrangements would be required to maintain consistency across Australia.


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26

Characteristics of Technical Standards 6.0

The standard should consist of several components to address the many facets independently, for example,

voltage control, protection systems and power quality. This would allow a checklist of requirements to be

produced to address the requirements one by one.

We consider that an effective connection standard should do the following:

Provide a single framework for a range of users with varying technical requirements

Promote a safe network environment to the public, electricity consumers and network personnel

Not adversely affect power system security

Not adversely affect quality of supply for other users

Have clarity and transparency of technical requirements

Support early identification of feasibility of connection

Be easily understood by the stakeholders

Lead to predictable and consistent outcomes

Lead to cost effective connection installations

Minimise the work required by both the DNSPs and EG proponents

Provide clarity on what technical requirements must be specified on a case-by-case basis

Clearly identify requirements for different generator class, voltage and connection point types

Provide clear and current reference to relevant external standards

Be self-contained to avoid constant cross-referencing as far as feasible

Have an appropriate level of prescriptiveness on connection requirements

Provide a minimum standard, where practical, and allow flexibility for optimisation so as to maximise

overall economic benefits.


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27

Summary and Recommendation 7.0

There is significant interest and appetite from all stakeholders involved in EG including the equipment suppliers,

developers, DNSPs and industry associations to develop a standard or suite of standards that address the

technical issues relating to the connection of EG within Australia. There are ways available to deal with the

obstacles and challenges in regard to the level of detail and treatment of location specific requirements. There is

sufficient and in-depth knowledge and experience to deal with these issues among the stakeholders. Overseas

experiences are available to supplement Australian experience.

The standard could contribute to achieving the objectives in regard to improving energy efficiency and reducing

impediments to EG investment. The standard could also contribute to improvement in the connection process and

engagement between the proponents and the connecting DNSPs.

A technical standard would offer benefits beyond immediate improvement in connection process clarity, outcome

predictability and cost to EG connections. It would contribute to improving national consistency and promote

common industry practices in distribution network planning, design and operations. It would also contribute to

standardisation of equipment which will further contribute to cost reduction in equipment, streamlined installations,

and operation consistency.

For the standard to promote overall improvement in economic efficiency of the electricity supply infrastructure, a

balanced approach and requirements should be applied in the development of the standard so as to achieve the

most efficient connection cost and cost allocations.

We consider that it is most appropriate that a standard rather than an industry guideline be developed. It is

preferable that the technical standard is not integrated with NER as WA and NT electricity markets are separate

from the NEM. Given the need for a nationally consistent approach, a Standards Australia process is the best one

available to be utilised for the development of this standard.

The standards should be referenced or enforced by relevant state and territory technical regulators.

The characteristics of the standard should be carefully defined and agreed, and should be used to guide the

standard development process. This is to ensure balanced and effective outcomes that support the stated policy

objectives.

Broad stakeholder participation in the development of this standard is crucial to its success because the standard

would impact on not only the technical requirements, but also business processes, risks, cost, and returns of

multiple parties. There was strong interest shown across the majority of stakeholders for being involved in the

development of a standard.

AECOM concludes that it is feasible to develop a technical standard for connection of mid-scale EG, and

recommends that a technical standard be developed and implemented.

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28

Glossary 8.0

Term Meaning

Generic

AEMC Australian Energy Market Commission

CEC Clean Energy Council

CoPEG Code of Practice for Embedded Generation

DG Distributed Generator

DNSP Distribution Network Service Provider

DSP Demand side participation

ECC Energy Efficiency Council

EG Embedded Generation

ENA Energy Networks Association (Australia or United Kingdom)

ENTSO-E European Network of Transmission System Operators for Electricity

HV High voltage greater than 1000 V AC or 1500 V DC

LV Low voltage of range 50–1000 V AC or 120-1500 V DC

MCE Ministerial Council on Energy

NECF National Energy Customer Framework

NEM National Electricity Market

NER National Electricity Rules

NWIS North-West Interconnected System

PCC Point of common coupling

RET Commonwealth Department of Resources, Energy and Tourism

RNIS Regional Non-interconnected systems

ROCOF Rate of change of frequency (protection against islanding)

SWIS South-West Interconnected System

TNSP Transmission network services provider

URF Utility Regulator’s Forum

Embedded Generator classification

Large Nameplate rating of 5 MW and greater

Medium Nameplate rating greater than 1 MW and less than 5 MW and connected to HV network

Micro Nameplate rating less than 2 kW AS4777 compliant and LV connected

Mid-scale Nameplate rating of between 30 kW and 5 MW, and non-inverter connected generators below 30

kW, and connected to a distribution network.

Mini Nameplate rating of greater than 2 kW and up to 10 kW single phase or 30 kW three phase, and

connected to the LV network.

Small Nameplate rating of greater than 10 kW single phase or 30 kW three phase, but no more than

1 MW, and connected to the LV network.

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29

References 9.0

9.1 Australian

9.1.1 Distribution Network Service Providers

[1] ActewAGL, 2009, “Guidelines for the connection of small generators in parallel with the ActewAGL

distribution network”, 30 Dec 2009

[2] ActewAGL, 2011, “Guidelines for photovoltaic installations up to 200kW connected via inverters to the

ActewAGL network”, 8 Nov 2011

[3] ActewAGL, “Large scale photovoltaic installations”, viewed 1 February 2013,

http://www.actewagl.com.au/~/media/ActewAGL/ActewAGL-Files/Products-and-services/Building-and-

renovation/For-professionals/CCA0212-48%20guidelines-NoContacts.ashx

[4] Aurora, 2012, “Guideline for the connection of embedded generators to the Aurora Distribution Network”,

NG R PD 08, Version 1.0, July 2012

[5] Aurora Energy, 2012, “Guideline for the Connection of Micro Embedded Generators to the Aurora

Distribution Network (AS4777 Compliant)”, Version 1.0, July 2012

[6] Ausgrid, 2011, “ES11 Requirements for Connection of Embedded Generators”, July 2011

[7] Ausgrid, 2011, “Electricity Network Operation Standards”, October 2011

[8] CitiPower, Powercor Australia, 2012, “Customer Guidelines for HV Connected Embedded Generation”,

Version 1.0, 29 Nov 2012

[9] CitiPower, Powercor Australia, 2012, “Customer Guidelines for Low Voltage Connected Embedded

Generation”, Version 1.0, 4 Sep 2012

[10] Energex, 2012, “Customer Standard for Small to Medium Scale Embedded Generation”, No. 03972 V2,

11 Jan 2012

[11] Horizon Power, Western Power, 2012, “Western Australian Distribution Connections Manual”,

DMS#7159802 v3, May 2012

[12] PowerWater, 2003, “Power Networks Network Connection Technical Code”, Revision 2.0, April 2003

[13] SA Power Networks, 2012, “Large Embedded Generation Network Connection – Customer Guide”, 7

Sep 2012

[14] Western Power, 2008, “User Guide for the connection of generators up to 10 MW to the Western Power

SWIN distribution system”, DMS#3065298v9A, July 2008

[15] Western Power, 2011, “Technical Rules for the South West Interconnected Network”, DMS#3605551v5,

23 Dec 2011

9.1.2 Other

[16] AEMC, 2009, “Review of Demand-Side Participation in the National Electricity Market – Final Report”, 27

Nov 2009

[17] AEMO,2010, “NEM Generator Registration Guide”, 1 December 2010

[18] Allen Consulting Group and NERA Economic Consulting, 2007, “Network Planning and Connection

Arrangements – national Frameworks for Distribution Networks”, Aug 2007

[19] Australian Business Council for Sustainable Energy, “Technical Guide for Connection of Renewable

Generators to the Local Electricity Network”, Aug 2004

[20] ClimateWorks Australia, Seed Advisory and the Property Council of Australia, 2011, “Unlocking Barriers

to Cogeneration – Project Outcomes Report”, Sep 2011

[21] ClimateWorks Australia, Seed Advisory and the Property Council of Australia, 2012, “Proposal to amend

the National Electricity Rules for connecting embedded generators”, April 2012

[22] ENA, 2008, “Embedded Generation – ENA Policy Framework Discussion Paper”, Nov 2008

http://www.actewagl.com.au/~/media/ActewAGL/ActewAGL-Files/Products-and-services/Building-and-renovation/For-professionals/CCA0212-48%20guidelines-NoContacts.ashx

http://www.actewagl.com.au/~/media/ActewAGL/ActewAGL-Files/Products-and-services/Building-and-renovation/For-professionals/CCA0212-48%20guidelines-NoContacts.ashx

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30

[23] ENA, 2011, “ENA Guideline for the preparation of documentation for connection of Embedded

Generation within the Distribution Networks”, May 2011

[24] Essential Services Commission of South Australia, 2010, “South Australian Electricity Distribution Code”,

EDC/09, 1 January 2003 (As last varied November 2010)

[25] Essential Services Commission of Victoria, 2012, “Victorian Electricity Distribution Code”, 31 May 2012

(version 7)

[26] MCE Standing Committee of Officials, 2008, “Electricity Distribution Network Planning and Connection –

A National Framework for Electricity Distribution Networks – Policy Response”, 15 Dec 2008

[27] MCE, 2010, “Demand-Side Participation in the National Electricity Market – Response to the Australian

Energy Market Commission’s Stage 2 Final Report”, No. 181, June 2010

[28] Office of the Tasmania Energy Regulator, 2005, “Tasmanian Electricity Code”, May 2005

[29] Office of the Tasmania Energy Regulator, 2005, “Electricity Supply Industry Act 1995”,

[30] PB Associates, 2006, “A National Code of Practice for Embedded Generation – Consultation Paper”, Feb

2006

[31] PB Associates, 2006, “A National Code of Practice for Embedded Generation - Draft”, Feb 2006

9.2 International

[32] ENA, 2003, “Engineering Recommendation G59/1, 1991 - Recommendations for the Connection of

Embedded Generating Plant to the Public Electricity Suppliers’ Distribution Systems”, 2003

[33] ENA, 2011, “Distributed Generation Connection Guide – A Guide for connecting generation that falls

under G59/2 to the distribution network”, Version 3.3, Nov 2011

[34] ENA, 2011, “Recommendations for the Connection of Generating Plant to the Distribution Systems of

Licensed Distribution Network Operators”, G59/2-1, Nov 2011

[35] ENTSO-E, 2012, “Network Code Requirements for Grid Connection Applicable to all generators –

Frequently asked questions”, 19 June 2012


Justification Outlines”, 26 June 2012


Requirements in the context of present practices”, 26 June 2012

[38] ENTSO-E, 2013, “ENTSO-E Network Code for Requirements for Grid Connection Applicable to all

Generators”, 8 March 2013

[39] IEEE, 2003, “IEEE 1547 Standard for Interconnecting Distributed Resources with Electric Power

Systems”, IEEE1547, 2003

[40] IEEE, 2012, IEEE 1547a Standard for Interconnecting Distributed Resources with Electric Power

Systems”, IEEE1547a, Amendment 1 in progress, 12 Sep 2012

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Appendix A

List of Stakeholders

AECOM



The following organisations were invited to attend the stakeholder consultations. Only Ausgrid and SA Power

Networks did not attend the consultation sessions. However, the similarity in DNSP’s views suggests that their

views are reasonably well represented by other DNSPs. The market institutions were informed of the consultation

process but not invited to the consultations.

Market Institutions (informed)

AEMC

WA Public Utilities Office responsible for WEM Rules

AER (informed but not invited to consultation)

AEMO (informed but not invited to consultation)


Queensland

Ergon Energy

Energex

New South Wales

Ausgrid

Essential Energy

Endeavour Energy

Australian Capital Territory

ActewAGL

Victoria

Jemena

CitiPower / Powercor

SP AusNet

United Energy

Tasmania

Aurora

South Australia

SA Power Networks

Western Australia

Western Power

Horizon

Northern Territory

PowerWater

Industry bodies

Energy Network Association (ENA)

Clean Energy Council (CEC)

Energy Efficiency Council (EEC)

Energy User Association Australia

Property Council of Australia

NT Treasury and finance

Carbon Reduction Ventures Pty

Equipment suppliers identified in consultation with CEC/EEC

Aquatec

Siemens

TSF Engineering

Grover Projects

AECOM



Responses to Interim Report

A wide variety of responses were received from the Interim Report. In some cases the responses were received

as part of an industry body response, mainly the ENA. Where a response was received through the industry body

it is noted. Parties that we received response from are listed below.


Queensland

Ergon Energy – through ENA

Energex – through ENA

New South Wales

Endeavour Energy

Networks NSW – through ENA


ActewAGL

Victoria

CitiPower / Powercor

United Energy – through ENA

Tasmania

Aurora – through ENA

Western Australia

Western Power – through ENA

Horizon Power

Industry bodies

Energy Network Association (ENA)

Clean Energy Council (CEC)

Energy Efficiency Council (EEC)

Property Council of Australia

Government body responses were received from

Victoria

Queensland


Western Australia

Australian Government

AECOM



Appendix B

Stakeholder Questionnaire

1 Introduction | AECOM Australia Pty Ltd

Introduction 1.0

1.1 Background

The Department of Resources, Energy and Tourism (RET) has engaged AECOM to conduct a feasibility study on

the development of a grid connection technical standard for mid-scale embedded generators. The purpose of this

project is to examine whether it is feasible to develop standards for connection of mid-scale embedded generation

to the electricity distribution networks in Australia.

This study will contribute to the delivery of the National Strategy for Energy Efficiency, that is, to “maximise the

potential for the application of cogeneration, renewables and other distributed generation technologies that

increase energy efficiency”.

The project will also support actions on the findings of the Australian Energy Market Commission (AEMC) that the

current framework for determining minimum technical standards creates an impediment to efficient connection of

embedded generators in the National Electricity Market. It will also provide support to non-NEM jurisdictions to

maximise the potential of deployment of embedded generators.

Outcomes of this project will advise and inform the Energy Market Reform Working Group under the Standing

Council on Energy and Resources (SCER), and the Energy Efficiency Working Group under the Select Council on

Climate Change (SCCC) as part of its decision making process regarding the standards.

1.2 Objectives

The aim of this questionnaire is to focus and supplement our consultation with stakeholders and support

conclusions on:

1. Whether it is feasible to “develop standards for connection of mid-scale embedded generation to

electricity distribution networks in Australia”; and

2. “how the development of these standards will support actions in the non-NEM jurisdictions: Western

Australia and the Northern Territory”.

1.3 Definitions

The Energy Networks Association provides a typical classification of embedded generation1 as follows:

Micro - Less than 2 kW AS4777 compliant and LV connected

Mini - greater than 2 kW and up to (10 kW single phase or 30 kW three phase) and connected to LV

network but not necessarily AS4777 compliant

Small – greater than (10 kW single phase or 30 kW three phase) but no more than 1 MW and connected to

the LV network

Medium – greater than 1 MW and less than 5 MW and connected to HV network

Large – nameplate rating of 5 MW and greater

This investigation defines mid-scale embedded generation to include elements of ENA’s mini, small and large

embedded generator categories:

Mid-scale – between 30 kW and 5 MW (and non-inverter connected generators below 30 kW) and

connected to a distribution network

1 ENA, “Guideline for the preparation of documentation for connection of Embedded Generation within Distribution Networks”,

May 2011, Table 1, page 8.

2 Questionnaire | AECOM Australia Pty Ltd

Questionnaire 2.0

Please address the questions that follow.

Question 1 What is unique to mid-scale generation that needs to be reviewed?

Do you consider the following technical aspects to require unique specification for specific mid-scale generators or suggested criteria?

Should the details be defined within the technical standard, should only the broader requirements be specified, or should these aspects be excluded altogether?

Please confirm uniqueness and inclusion of each aspect with either a tick or a cross.

Please add any new criteria to one of the empty rows or add a blank sheet to the questionnaire. Space for general comments is provided at the end of this section.

CUO = continuous uninterrupted operation

PCC = point of common coupling

Aspect Unique to

mid-scale

compared

to smaller

non-mid-

scale

generators

Unique to

mid-scale

compared

to larger

non-mid-

scale

generators

Unique to

larger

mid-scale

generator

s greater

than 1 MW

Unique to

asynchro-

nous

Unique to

synchro-

nous

Unique to

voltage

Unique to

PCC

Required

with

connection

application

Required

with

connection

application

on a case-

by-case

basis

Should be

included in

technical

standard

Details

should be

included in

technical

standard

1. Protection systems and impacts

Generally

Redundancy

Failsafe

Main & backup

Synch. & check

Anti-islanding

Over & under

frequency

Over and under

voltage


Neutral voltage

displacement

Overcurrent and

earth fault

Negative phase

sequence and

current

Pole-slip

Breaker fail

Inter-trip

Impact on network

protection settings

near PCC

2. Reactive power capability

Capable of

supplying or

absorbing specific

amount at any

voltage

Power factor limits

3. Power quality

Harmonic distortion

Voltage fluctuation

and duration

Voltage unbalance

Inductive

interference

Negative sequence

voltage


CUO enduring

voltage fluctuation

and unbalance, and

harmonic voltage

distortion within

required levels at

PCC

4. Response to frequency disturbances

lower bound of

extreme frequency

excursion limit for

transient frequency

time

Upper bound of

extreme frequency

excursion limit for

transient frequency

time

5. Response to voltage disturbances

CUO within specific

band for specified

duration

6. Response to disturbances following contingency events

Relative fault level

contribution

Fault types e.g.

earth faults

Fault clearance

times

Breaker fail

Deliver active and

supply or absorb


reactive power

Deliver active and

supply or absorb

reactive power to

maintain PCC

voltage at required

level

7. Partial load rejection

CUO following load

reduction of X%

from

predisturbance

level

8. Frequency control

Active power must

not increase in

response to a rise

in frequency

Active power must

not decrease in

response to a fall in

frequency

Automatic active

power response to

frequency

excursions outside

normal operating

limits

No active power

response to

frequency changes

9. Impact on Network Capability


Transient stability

Small signal

stability

Voltage stability

10. Voltage and reactive power control Excitation control system

10.1. Plant capabilities and control systems

Adequate damping

Does not degrade

critical mode of

oscillation

Does not cause

instability

10.2. Control system

Monitoring and

recording facilities

Facilities for testing

dynamical

operational

characteristics

10.3. Excitation control system for synchronous generating system

Voltage control

Reactive power

Continuous voltage

setpoint control

over range 95-

105% of normal

voltage

Limiting devices to


prevent trip

Specific excitation

ceiling voltages

Specific Settling

times

Specific rate of field

voltage increase

Power system

stabiliser

Settable reactive

current

compensation

10.4. Voltage control system for non-synchronous generating units

Regulate voltage

Regulate power

factor

Regulate reactive

power

Regulation within

specified tolerance

Continuous voltage

setpoint control

over range 95-

105% of normal

voltage

Limiting devices to

prevent trip

Specific excitation

ceiling voltages

Specific Settling


times

Specific rate of field

voltage increase

Power system

stabiliser

Settable reactive

current

compensation

10.5. Power system stabiliser (if applicable)

Measurements of

rotor speed or

system frequency

and active power

output as inputs

Washout filters

Lead-lag transfer

function blocks with

adjustable gain and

time-constants

An output limiter

Monitoring and

recording facilities

Facilities to test the

PSS in isolation

11. Active power control

Automatic control of

active power output

in response to

remote instructions

Automatic control

within specific


change tolerances

and limits

12. Monitoring & control

12.1. Remote monitoring

Real-time remote

monitoring

equipment to

transmit to DNSP

Active and reactive

power

Number of wind

farm units online,

wind speed and

direction, ambient

temperature

Active power

metering

Reactive power

metering

12.2. Communications equipment

Separate

independent

telephone facilities

for communications

with DNSP

Facilities to

maintain remote

monitoring and

control equipment

available for at

least one hour

13. Safety


Safe shutdown

without external

supplies

Isolation

Solid earthing

Impedance earthing

Different treatment

where auxiliary

supplies via a

different PCC to

where the

generation is

transferred

Interlocking to

prevent parallel

operation

Specific

environmental

requirements due

to potential close

proximity to

neighbours

11 Contact Details | AECOM Australia Pty Ltd

Question 2 What are your organisation’s appetite and requirements for this standard?

Question 3 What are the embedded generator proponent’s needs that a standard can address?

Question 4 How can the technical requirement be balanced with financial considerations?

Question 5 What are the critical requirements to ensure reliability and safety and quality of supply to

existing customers?

Question 6 What are the most appropriate scope and level of details for a connection standard?

Question 7 Further comments

Contact Details 3.0

Please direct queries on this questionnaire, or its validity, to either of the contacts provided below:

Department of Resources, Energy and Tourism AECOM

Michael Whitfield

Assistant Manager

[email protected]

Phone +61 2 6213 731451

Demand Side Policy

Energy Division

Department of Resources, Energy & Tourism

Allara St, Canberra

GPO Box 1564

Canberra ACT 2601

Colin Watson

Associate Director – Connection Services

D +61 7 3553 3408 M +61 403 976 134

[email protected]

Level 8, 540 Wickham Street, Fortitude Valley,

QLD 4006

PO Box 1307 Fortitude Valley QLD 4006

T +61 7 3553 2000 F +61 7 3553 2050

www.aecom.com

mailto:[email protected]

http://www.aecom.com/

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