IEEE GUIDE FOR Load Side Smart Grid InteroperabilityIEEE Preliminary Draft 0.1

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IEEE Std P2030 Draft Guide for Smart Grid Interoperability of the Electric Power System

(EPS) Framework for Describing Load Side

Prepared by the Load Side Sub-Group of

Taskforce 1, Power Engineering Technology of IEEE SCC21 P2030

Copyright © 2009 by the Institute of Electrical and Electronics Engineers, Inc.Three Park AvenueNew York, New York 10016-5997, USAAll rights reserved.

Load Side Outline Proposal for TF1

Date: 2010-03-01

Author(s):Name Affiliation Address Phone email

Greg Bernstein Grotto Networking Fremont, California, USA (510) 573-2237 gregb@grotto-

networking.com

Liang Downey

Nextek Power Systems Detroit, MI 313-887-1321 Liang.downey@nexte

kpower.comKim Mosley KYMS Consulting Chino, CA 909-851-6299 Mosleyk2@asme.org

This document is an unapproved draft of a proposed IEEE guide to the XXXX series of XXX guides on Smart Grid Interoperability of the EPS for application in transmission substations. As such, this document is subject to change. USE AT YOUR OWN RISK! Because this is an unapproved draft, this document must not be utilized for any conformance/compliance purposes. Permission is hereby granted for IEEE Standards Committee participants to reproduce this document for purposes of IEEE standardization activities only. Prior to submitting this document to another standards development organization for standardization activities, permission must first be obtained from the Manager, Standards Licensing and Contracts, IEEE Standards Activities Department. Other entities seeking permission to reproduce this document, in whole or in part, must obtain permission from the Manager, Standards Licensing and Contracts, IEEE Standards Activities Department.

IEEE Standards Activities DepartmentStandards Licensing and Contracts445 Hoes Lane, P.O. Box 1331Piscataway, NJ 08855-1331, USA

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IEEE Std P2030 Draft Guide for Smart Grid Interoperability of the Electric Power System (EPS)

Framework for Describing Loads and Load Side Applications

1. Overview of Loads and Load Side Applications (End Use Applications)

This document provides description of electric loads that consume energy and end-use applications aimed at demand response for load shedding in the context of smart grid. Integration of electrical, information and communications technology is necessary to achieve seamless operation for electric generation, delivery, and end-use, enabling multi channel power flow between sources of power and devices that consume or store power. The development of advanced power electronics, communication and control technologies is making it possible to make the grid smart, by using power when, where and how it is generated efficiently and reliably. Interconnection and intra-facing frameworks and strategies with design definitions are addressed in this standard, providing guidance in expanding the current knowledge base. This expanded knowledge base is needed as a key element in grid architectural designs and operation to promote a more reliable and flexible electric power system.

1.1 Load Description1.1.1. Residential

The largest use of electricity in the average U.S. household was for appliances (including refrigerators and lights), which consume approximately two thirds of all the electricity used in the residential sector. Air-conditioning accounted for an estimated 16 percent, space heating 10 percent, and water heating 9 percent; No single appliance dominated the use of electricity. Refrigerators consumed the most electricity (14 percent of total electricity use for all purposes), followed by lighting (9 percent), clothes dryers (6 percent), freezers (3 percent), and color TV’s (3 percent). 1

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Surce: http://www.eia.doe.gov/emeu/recs/recs2001/enduse2001/figure1.html

1.1.2. Commercial Buildings

Table E5A. Electricity Consumption (kWh) by End Use for All Buildings, 20032

 

Total Electricity Consumption (billion kWh)

Total

Space Heat-ing

Cool-ing

Venti-lation

Water

Heat-ing

Light-ing

Cook-

ingRefrig-eration

Office Equip-ment

Com-puters Other

All Buildings .......................... 1,043 49 141 128 26 393 7 112 20 46 122

The largest load in commercial building sector is lighting. It consumes about 40% of the total energy in this sector. Next in line is cooling and ventilation

1.1.3. Industrial

Below is a sample data provided by DOE EIM for energy used in1998.Net

Electricity(b)End Use (million kWh)

ALL MANUFACTURING INDUSTRIESTOTAL FUEL CONSUMPTION 889,474Indirect Uses-Boiler Fuel 5,568Direct Uses-Total Process 705,697 Process Heating 103,299 Process Cooling and Refrigeration 54,473 Machine Drive 457,344

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Revision 0.1 Electro-Chemical Processes 87,200 Other Process Use 3,380Direct Uses-Total Nonprocess 157,736 Facility HVAC (g) 79,355 Facility Lighting 61,966 Other Facility Support 14,338 Onsite Transportation 1,380 Conventional Electricity Generation -- Other Nonprocess Use 696

The largest load in the manufacturing process is Machine Drive which run motors. Facility use of energy centers around Lighting and HVAC

1.1.4. Transportation Sector

Plug-In Vehicles (PEV) include both Battery Electric vehicles (BEV) and plug-in hybrid vehicles (PHEV) types and are further diversifying electrical load in the transportation sector. IEEE 1890 “Title” will develop applicable standards for this sector therefore the discussion in this document will be restricted to load characterization and system interoperability. Although the number of BEV and PHEVs on the road is relatively small, only consuming XXXMWh average daily usage of electricity, increased demand for these new forms of environmentally friendly vehicles has occurred with both personal and commercial users. It is estimated that by the year 2030 PHEV will add XXXMW of load demand or consume XXMWh of power. It is critical that the energy industry strategically meet the consumption needs of this very important and growing sector.

1.2 Load Characteristics and Analysis Common to all industries, Lighting, HVAC, Electric Drives to Run Machines (including EV/PHEV) and Computer/Communication equipment are key loads that use the vast majority of the electricity.

1.2.1 DC Loads Fed with AC Power from Transmission Grid (legacy)Since the advent of semi-conductors in the 1950’s, their ubiquity has steadily grown to the point where electronic devices are the fastest growing sector of the total load globally. All microprocessors require direct current (DC) and many devices operate internally on DC power since it can be precisely regulated for sensitive components, such as electronics ballasted lighting, LEDs, Variable speed drive to run motors for HVAC and machines in the factory, and of course all computing, communication equipment and digital consumer devices.Building electrical systems are fed with AC that is converted to DC via power supply to every electronic device. This is because the legacy AC networks are dominant due to its primary advantage over DC as a superior medium for long distance transmission from wholesale power generating stations to their distant customers- loads.

1.2.1.1 Interconnection, grid connected-ness, AC input, DC use

1.2.1.1.1 PEVs

The ideal usage or consumption mode for PEVs is overnight charging and no charging during peak times. The EV Supply Equipment (EVSE) is described in SAE J1772™ and has three types. AC Level 1 is a 120V

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Revision 0.1mobile cord-set and connects to a standard 15A outlet to deliver 1.4 kW. AC Level 2 is a 240V premise mounted unit (dedicated utility feed) designed to allow 19.2 kW charging, but most will connect to a 40A circuit breaker capable of only delivering 7.68 kW. The 3rd type of EVSE is DC where the unit includes an off-board charger.

Level 1 will require no modifications to the home however more time will be required to charge the PEV. Level 2 requires a special unit to be installed at the home or business and the DC version of the unit could accommodate both Level 2 and level 3 charging. When the PEV uses Level 2 equipment, but has a smaller on-board charger, the smaller of the EVSE Available Line Current (ALC) or on-board charger establishes the power delivered and time required (e.g. the EVSE is capable of delivering 7.68 kW but the on-board charger is 3.3 kW, only 3.3 kW will be used). Initial model PEVs are expected to include a 3.3 kW on-board charger but may quickly move to 6.6 kW or use the DC EVSE. The advantages of the DC EVSE are that the customer purchases this larger charger once and not with each vehicle.

The impact of these charging options and period is that the PEV loads are sustained over the non peak times but will increase the average load for the home or business. Substation or charger? transformer reliability is also based on nighttime cooling and this represents the optimum condition or period for charging PEV loads.

A summary of BEV vs. PHEV charge times is as follows:

• Level 1 – (120V) 1.4 kW-PEVincludes 3.3kW charger?• PHEV takes 7 hours (starting at 0% SOC)• BEV takes 17 hours (starting at 20% SOC)

• Level 2 – (240V) up to 19.2 kW (80A)• Most installations are connected to 40A CBR (7.68 kW)• PEV includes 3.3kW chargers

• PHEV takes 3 hours to charge• BEV takes 7 hours

• PEV includes 7 kW charger• PHEV takes 1.5 hours to charge• BEV takes 3.5 hours• Advantage - Closer match to EVSE capacity, faster charge times (1/2 of 3.3 kW)

• DC Level 3 or Level 3 (up to 20 kW – 80A).• PHEV charges in 22 minutes (0 to 80% SOC since faster than 1C rate-this needs

explaining)• BEV charges in 1.2 hours (20% to 100% SOC).

Notes: BEV always starts at 20% SOC, PHEV can go to 0% SOC since hybrid mode is available.Anything faster than a 1C rate only goes to 80% due to battery restraints (for now).

1.2.1.1.2 External Power Supply voltage, current, efficiency, power factor1.2.1.1.3 Internal Power Supply voltage, current, efficiency1.2.1.2 Electrical properties of the components ports/wires1.2.1.3 Unique device ID, needed to be identifiable on the grid1.2.1.4 General device characteristics: type, manufacturer, Energy Star rating1.2.1.5 Equipment operator, for use in billing/credit with a mobile device such as PEV

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Revision 0.11.2.2 DC Loads Fed with DC Power from Distributed Energy Resources (emerging)

There are 2 large global trends afoot that are changing the status quo. The first of these is the growth in distributed power generating resources (DG), especially renewable one such as solar PV and small wind turbines. Each of these resources is intrinsically DC. The other trend creating the opportunity for DC power networks is the increasing density of electronic loads that themselves are DC power consumers. Therefore, in applications where DG sources are close to DC loads and there is no need for long distance transmission, DC power networks have proliferated, the country of Japan has recognized a DC IT standard and an industry consortium has formed to promote common DC power standards worldwide.

The key benefits DC power networks bring are avoided conversion losses, superior compatibility with power storage techniques and renewable energy, all leading to higher integrated system efficiencies on the order of 25%

1.2.2.1 Interconnection, grid connected-ness, DC input, DC use1.2.2.1.1 DC power supply voltage, current, efficiency1.2.2.2 Electrical properties of the components ports/wires1.2.2.3 Unique device ID, needed to be identifiable on the grid1.2.2.4 General device characteristics: type, manufacturer, Energy Star rating1.2.2.5 Equipment operator, for use in billing/credit with a mobile device such as PEV

1.2.3 Legacy AC LoadAlthough there are many legacy loads still powered by AC, there is less and less pure AC load as the world is continuously going digital. Before the widespread adoption of DC micro-grid, an hybrid DC/AC system will allow DC loads (new) to receive power from DC sources (new) and AC loads (old) to continue receive power from AC sources (old).

1.2.3.1 Interconnection, grid connected-ness, AC input, DC use1.2.3.1.1 AC power supply voltage, current, efficiency, power factor1.2.3.2 Electrical properties of the components ports/wires1.2.3.3 Unique device ID, needed to be identifiable on the grid1.2.3.4 General device characteristics: type, manufacturer, Energy Star rating1.2.3.5 Equipment operator, for use in billing/credit with a mobile device such as PEV

1.3 Load Applications The equation between energy supply to energy demand is in-balanced today due to many technological, historical and economical reasons. The idea of a Smart Grid is to break the bottleneck between the demand and the supply making the grid smart so as to reduce usage or deliver less power at the source via higher efficiency to meet the same level of load demand.

1.3.1 Energy Efficiency ApplicationsIt is generally thought that an increase in energy efficiency is when either energy inputs are reduced for a given level of service, or there are increased or enhanced services for a given amount of energy inputs3

1.3.1.1 Appliance EfficiencyMany appliances manufactured today are with much higher efficiency than earlier generation product. Taking lighting as an example, U.S. commercial buildings used a total of 352 billion kWh of electricity for lighting in . CBECS data suggest greater energy savings will occur by replacing existing fluorescent in 1995. Lights with more energy-efficient equipment such as electronic ballasts, which increase fluorescent

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Revision 0.1efficiency by up to 25 percent. There remains a significant fraction of commercial building floor space that can be upgraded with more energy-efficient lighting equipment4

1.3.1.2 Power Distribution Efficiency – DC Microgrid and Community Power In applications where DG sources are close to DC loads and there is no need for long distance

transmission, DC power networks have proliferated. The key benefits DC power networks bring are avoided conversion losses, superior compatibility with power storage techniques (battery) and renewable energy, all leading to higher integrated system efficiencies on the order of 25%

Using DC Microgrid for DC loads will reduce the need to build long distance transmission line to move prime power, alleviating the dependence on the grid transmission line. Similar to what happened to the computing industry for the past 50 years, it moved from main frame based computing to very distributed computing architecture known today as internet. The vision of internet for power is become a reality today.

1.3.2 Energy Management1.3.2.1 Smart Meters, monitoring, data acquisition and control example

Smart Meters are a fundamental component of Advanced Metering Infrastructure (AMI). Residential, Commercial and Industrial (C&I) Smart meters are digital meters that communicate energy use information to utilities, customers and possibly to other parties such as competitive retail suppliers.

The key enabler of many of the smart meters abilities is the implementation of two-way communication. Two-way communication facilitates at the meter level remote device configuration and firmware updates, and at the application level it provides:

Remote connect and disconnect for service restoration and interruption Energy usage data reporting at predetermined intervals and Time Of Use Outage detection and power restoration notification Advanced functionality like load limiting (limiting load to a preset level) remote service switch Monitoring and Control capabilities thru Home Area Network (HAN) connectivity allowing

demand response and load control capabilities. The HAN will allow customer to remotely connect to and control many different automated devices. Smart meters could also communicate thru the HAN peak times and enable control of smart appliances such as Smart refrigerators, thermostats and water heaters.

1.3.2.2 Home Gateway

The Home Gateway (HG) is a device that connects multiple home network devices (HAN/LAN) to an access Network (WAN). Typically, Wi-Fi or Ethernet provide the higher bandwidth connection from cable companies and utilities, and Zigbee or other competitive products provide bandwidth to low power devices such as thermostats, in-home displays, refrigerators and other smart appliances. Instead of a dedicated in-home

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Revision 0.1gateway device, the HAN gateway may be in the future integrated in the Smart meters to provide in-home energy management program and services.

In the smart grid application, the HAN hub can provide consumers with energy usage data and serve as gateway to the Smart Grid for energy management, grid reliability and demand response. Non-proprietary communication protocol and devices interoperability are key to the success of the HAN interaction with the grid and its evolution.

1.3.2.3 TOU and Tiered Rates

Time of use, or tiered, rates encourage the customer to shift their use of appliances and other loads from on peak to off peak hours. These rates generally take two forms: different prices for energy in cents per kWhour, and a difference in demand charge in cents kW based on the maximum demand in a specific period, perhaps 15 minutes, during on peak hours. Depending on the geographic location of the power system and the season, there may be a need for raising the rate for two peak periods during the day, for the morning and afternoon peaks, or for just one peak period. A tiered time of use rate may have three or more levels. For example, 20 cents/kWhr during peak times, 7 cents/kWhr during shoulder times, and 1 cent per kW/hour off peak. When the customer is presented with this rate structure, he voluntarily plans his daily routine to shift usage of dishwashers, clothes dryers, ovens and air conditioning to the less expensive off peak hours.

Some loads, such as pool filter pumps or irrigation pumps, are natural candidates for time of use and shifting their use to off peak times will cause no inconvenience to the customer. Other major loads may rely on inherent energy storage to make the shift less burdensome. For example, because water heating accounts for about 18 percent of typical home energy use, some utilities will offer a clock switch to shift the time the heating elements are on to off peak hours. In this case, a larger tank is useful to provide storage capacity. A water heater can be a remarkably effective energy storage device. As buildings are designed with features to store energy, time of use or tiered rates will become useful to larger percentages of customers.

1.3.2.4

1.3.3 Demand ResponsFrom [FERC] italics added:

The Commission uses the term demand response to refer to the ability of customers to respond to either a reliability trigger or a price trigger from their utility system operator, load serving entity, regional transmission organization/independent system operator (RTO/ISO) or other demand response provider by lowering their power consumption. For many years, the term was used to refer to peak clipping actions that were confined to a limited number of hours of the year. As adopted in Order No. 719, the Commission defined demand response to mean “a reduction in the consumption of electric energy by customers from their expected consumption in response to an increase in the price of electric energy or to incentive payments designed to induce lower consumption of electric energy.” Demand response can be both dispatchable and non-dispatchable.

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Revision 0.1Dispatchable demand response refers to planned changes in a customer’s consumption in a response to direction from someone besides the customer. It includes direct load control of customer appliances such as those for air conditioning and water heating, directed reductions in return for lower rates (called curtailable or interruptible rates), and a variety of wholesale programs offered by RTOs/ISOs that compensate participants who curtail loads when directed for either reliability or economic reasons. This direction to reduce load can be in response to acceptance of consumer’s bid to sell its demand reduction at a price in an organized market (a wholesale price responsive demand response) or to be sold to a retail provider. Non-dispatchable demand response refers to programs and products in which the customer decides whether and when to reduce consumption based on a retail rate design that changes over time. This is sometimes called retail price-responsive demand and includes dynamic pricing programs that charge higher prices during high-demand hours and lower prices at other times.

As used in this Discussion Draft, the term demand response includes consumer actions that can change any part of the load profile of a utility or region, not just the period of peak usage. As a result of technology innovations and policy directions, new types and applications of demand response are emerging. In particular, consumer response to signals from a utility system operator, load-serving entity, regional transmission organization/independent system operator (RTO/ISO), or other demand response provider, can be deployed to shape any or all parts of a customer’s load profile. This concept of autonomous demand response encompasses the effect of smart appliances in customer dwellings that can respond in near real-time to the signals of a load-serving entity, or other demand response operator, or to changes in bulk power system conditions such as a change in system frequency and/or voltage. No dedicated communications are needed between loads and the system operator. Depending on the type of load as well as power system needs, adjustment of power consumption would be simply turning the load on or off, or controlling the settings of control parameters. For example, in the case of washers and dryers, a typical response would shut off internal heating elements due to system frequency fluctuations. For loads with some type of energy storage, such as air conditioning units and water heaters, the response would be adjustments up or down of the thermostat settings over a pre-defined period. Interference with the normal functions of customer appliances or devices is kept at a minimal and often unnoticeable level. It also includes the smart integration of changeable consumption with variable generation to enable the addition of new technologies such as wind farms and roof top solar systems to utility systems. Demand response also includes deployment of devices that can manage demand as needed to provide grid services such as regulation and reserves, and can also draw power from energy storage devices such as plug-in hybrid electric vehicle batteries to provide these same grid services. Demand response can go beyond simple reduction in peak period consumption to include shifting consumption from peak to off-peak hours. For example, the use of energy storage devices may be advanced through the use of time-of-use rates that encourage night-time charging of home energy storage systems, plug-in hybrid vehicles and all-electric vehicles.

1.3.3.1 Categories of Demand Response Systems

From [NYISO]:

1. Energy Efficiency programs reduce electricity consumption and usually reduce peak demand2. Price Response programs move consumption from day to night (real time pricing or time of use)3. Peak Shaving programs require more response during peak hours and focus on reducing peaks every high-load

day

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Revision 0.14. Reliability Response (contingency response) requires the fastest, shortest duration response. Response is only

required during power system “events” –this is new and slowly developing5. Regulation Response continuously follows the power system’s minute-to-minute commands to balance the

aggregate system –this is very new and may have the potential to dramatically change production costs, especially for aluminum and chlor-alkali

6. Autonomous Response loads in the power system can adjust their usage of electricity based on system frequency and/or voltage deviations. No dedicated communications between load and system operator are needed.

Examples of older Price response and Peak Shaving programs from PG&E are summarized in the following table:

Name Simple Description CommunicationsCritical Peak Pricing (CPP)

Provides lower energy rates on non-CPP event days in exchange for higher rates on CPP event days

e-mail, text messaging, 3PM the day ahead

Demand Bidding Program (DBP)

Pays you an incentive to reduce your electric load according to a bid that you submit. For each event you may elect to submit or not submit a bid (minimum duration 2 hours, minimum reduction 50kW)

e-mail, text messaging, day-ahead, day-of (1 hour to submit bid, 15 minute notification of acceptance to reduction)

Base Interruptible Program (BIP)

Pays you an incentive to reduce your facility's load to or below a level that is pre-selected by you. This pre-selected level is called the Firm Service Level (FSL). Penalties for not meeting this level during an event. No more than 10 events per month, 120 hours per year. (minimum reduction 100kW)

e-mail and fax, 30 minutes advanced notice

These programs have only available to customers with with billed maximum demand of 200kW or greater and require a remotely readable interval type meter.

A more modern program is PeakChoice™ that provides numerous options:

Options Description

Participation level

Committed: Participants receive guaranteed monthly incentives for committing to reduce electricity consumption when called upon. The higher your commitment, the higher the monthly incentives you'll earn. If you select PeakChoice Committed but are unable to meet your agreed upon reduction, some penalties may be incurred.Best Effort: Decide, on the spot, whether your company can respond to PeakChoice reduction events. Earn incentives when PG&E notifies you and you're able to reduce your electricity. Once notified, you have up to two hours to respond and confirm your participation. If you are not able to reduce your electricity when asked, no problem (and no penalty).

Advance Notice

Decide how much "advance" time your company needs in order to reduce consumption. Choose from two days, one day, four hours or 30 minutes.

Reduction Size

Determine the amount of electrical reduction you can accommodate.

Timing Select between weekdays from 1 p.m. to 7 p.m. or 24 hours a day, seven days a week.

Total Days Select the total number of days you are able to participate.

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Revision 0.1To participate in this program one must have internet access with e-mail, and be able to curtail at least 10kW of demand.

Note that the above methods deal with relatively long advance notice or response times. Reference [NYISO] discusses the use of demand response systems to provide ancillary services. A summary of ancillary services that could be aided by load side control is given in the following table [NYSISO]:

Service Service DescriptionResponse Speed Duration Cycle Time

Normal ConditionsRegulating Reserve

Online resources, on automatic generation control (AGC), that can respond rapidly to system-operator requests for up and down movements; used to track the minute-to-minute fluctuations in system load and to correct for unintended fluctuations in generator output to comply with control performance standards (CPSs) 1 and 2 of the North American Electric Reliability Council (NERC 2006)~1 min Minutes Minutes

Load Following or Fast Energy Markets

Similar to regulation but slower. Bridges between the regulation service and the hourly energy markets. Supplied by the 5 minute energy market.~10 minutes 10 min to hours 10 min to hours

Contingency Conditions10 Minute Spinning Reserve

Online generation or responsive load, synchronized to the grid, that can increase output immediately in response to a major generator or transmission outage and can reach full output within 10 min to comply with NERC’s Disturbance Control Standard (DCS)Seconds to < 10 min 10 to 120 min Hours to Days

10 Min Non-Synchronous Reserve

Same as spinning reserve, but need not respond immediately; resources can be offline but still must be capable of reaching full output within the required 10 min<10 min 10 to 120 min Hours to Days

30 Min Operating Reserve

Same as non-synchronous reserve, but responds within 30 minutes; used to restore spinning and non-synchronous reserves to their pre-contingency status

< 30 min 2 hours Hours to DaysOther ServicesVoltage Control

The injection or absorption of reactive power to maintain transmission-system voltages within required rangesSeconds Seconds Continuous

As can be seen from this table that the reaction time from the load to participate in some ancillary services is significantly faster than that for price response or peak shaving, but relatively reasonable for smart grid.

1.3.3.2 Categorizing Loads for Demand ResponseThe aim of this section is to characterize loads in a manner that allows their use in any of the five previously defined categories of demand response systems to which they apply (energy efficiency, price response, peak shaving, reliability response, regulation response).

1.3.3.2.1 Individual Load Properties

The raw electrical characteristics, capabilities, and limitations of a device.

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Revision 0.1Electric Current consumption (real time & historical)

a. Example: "Current Transformer Encoding Module" [SEQ] -- such a devices is used to measure either large residential loads or appliances via current transformer measurements.

Example: Embedded measurement from smart appliances

1.3.3.2.2 Individual Load Usage1.3.3.2.3 Aggregated Load Property and Use

Load profiles, historical, weather related, etc…

Residential "Home Energy Gateway"a. Example: see [SEQ].

1.3.3.2.4 Aggregated Load Property and Use1.3.4 Load Control1.3.5 Direct Load Control

Utility or (intermediary) directly controls an individual device such as A/C, pool pump, etc., by communicating "directly" with it (e.g., pager systems, etc…)

1.3.5.1 Direct Load Control (on/off)1.3.5.1.1 Example: 30A contactor (roughly an on/off relay) for general use via local radio control [SEQ]1.3.5.1.2 Example: remote control power outlets [SEQ].1.3.5.2 Themostat (HVAC)1.3.5.2.1 Example: wireless HVAC module for thermostat upgrade (preserves existing thermostat) [SEQ]1.3.5.2.2 Example: New smart thermostats with smart grid or home gateway interfaces

1.3.6 In-direct Load ControlUtility or (intermediary) directly controls an individual device such as A/C, pool pump, but communicates with some type of gateway rather than talking to the device itself.Home gateways? [SEQ]

1.3.7 Aggregate Load ControlHere a utility or intermediary talks to some type of load aggregator. This interface is being standardized as part of the OpenADR [OpenADR] efforts. Smart home gateways seem like they can act as an aggregate load controller too [SEQ].

1.4 Load Side Power Distribution Topology: Hybrid DC/AC System

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1.4.3 Load Centric Grid – New Meaning for Smart GridTraditionally the focus of the power industry has been on the grid, but the grid is not a mean to itself. The grid was invented to serve the power needs of the load, if instead we put the LOAD as the center of the attention, we will come up with different kinds of ideas on how best to send power to the load either locally or remotely. The concept of smart grid will carry on new meaning.

The concept of Zero Energy Building is to promote the idea that a building must have a mean to generate its own power to serve the building’s power needs. Keep the Zero Energy Building concept in mind, any renewable energy or onsite energy system should be designed according to the needs of the load. If the peak generation is matched to the load, then every clean watt will be utilized without any conversion loss. During the none-peak period of the renewable generation, utility grid power will come into play to make up the difference, therefore accomplishing a true peak shaving in the most efficient way.

Because renewable or onsite energy sources are still very expensive to implement, although “selling excess power back to the utility” via “feed-in” tariff is a nice to have concept, it does not make economic sense in reality. With government rebate and tax incentives, we are still talking about $2-3/KWH for the installed cost of Solar PVs, for example, even if user can sell the excessive solar power back to the utility, at most, user is getting paid at the whole sale rate of the KWH, say 10cents/KWH. Secondly, selling precious solar power back to utility, an inversion process is un-avoided converting DC power to AC, at the electronic load side, the load will again convert the AC back to DC either internal or externally. These added conversions contribute to further energy loss. Sizing the renewable generation capacity to match the load is a mean to avoid these un-necessary loss.

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Revision 0.11.4.4 Hybrid AC/DC Microgrid – Distributed Energy

In the not too distant future, all loads will be electronics driven thus DC in nature, therefore a DC micro-grid makes perfect sense for energy efficiency, simplicity and reliability purposes. But before that, a hybrid AC/DC system will act as an interim solution while more and more loads are becoming DC-ready.

In the hybrid AC/DC system, most if not all renewable/onsite DC generation will be used to power directly the DC loads, and AC power will continue to supply power to the legacy AC loads. An energy transfer mechanism allowing multiple paths to exist, (1)sending utility AC power to DC loads to make up the shortage of renewable supply, (2)supplying excessive DC power back to utility grid to power the existing AC legacy loads, (3)charge battery, etc., will require a smart power router device to act as inverter/rectifier/converter combined.

1.4.5 Inverters/Converters – Renewable Energy at Long Distance1.4.5.2 Inverters - HVAC

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IEEE GUIDE FOR Load Side Smart Grid InteroperabilityIEEE Preliminary Draft 0.1

Revision 0.1For solar PVs or wind mills installed as a power plant or wind farm that harvest renewable energy to be transferred to areas that do not have sufficient renewable energy sources, an inverter solution will be needed to convert the generated DC power to AC to be synchronized with the high voltage transmission line at 50/60hz .

1.4.5.3 Converters - HVDCHVDCs have existed and are in the talk again to move electricity in the form of DC (kv) in long distance. HVDC offers economic benefits due to the savings on copper (2 wire in DC vs. 3 wire in AC), and simplicity due to the avoidance of managing 2-phase power and power factor correction. A boost convert will be necessary to increase the DC voltage from solar PV to kv level at the sending end, and a buck converter at the receiving end to down convert the high voltage DC to a lower voltage to be used by the loads. DC-DC converters are simpler to design and require less components than inverters

1.5 Communication and Networks

1.5.3 Protocols1.5.3.2 LAN, WAN, HAN, SCADA1.5.4 Electrical protection and network security (fault isolation, switching and islanding)

References:1: US DOE Energy Information Administration: http://www.eia.doe.gov/emeu/recs/recs2001/enduse2001/enduse2001.html

2: US DOE Energy Information Administration: http://www.eia.doe.gov/emeu/cbecs/cbecs2003/detailed_tables_2003/detailed_tables_2003.html#enduse03

3: US DOE Energy Information Administration: http://www.eia.doe.gov/emeu/efficiency/definition.htm

4: US DOE Energy Information Administration: http://www.eia.doe.gov/emeu/cbecs/lit-type.html

[NYISO] B. Kirby, M. Starke, S. Adhikari, "NYISO Industrial Load Response Opportunities: Resource and Market Assessment—Task 2 Final Report", Oak Ridge National Laboratory, ORNL/TM-2009/147, October 2009. Available from: http://certs.lbl.gov/pdf/lbnl-2490e.pdf .

[FERC] Federal Energy Regulatory Commission Staff, "Possible Elements of a National Action Plan on Demand Response - A DISCUSSION DRAFT -, DOCKET NO. AD09-10, October 28, 2009. Available at: http://www.ferc.gov/EventCalendar/Files/20091028124306-AD09-10-000-Discussion.pdf .

[PGE] See Demand Response info at: http://www.pge.com/demandresponse/

[OpenADR] California Energy Commission, "OPEN AUTOMATED DEMAND RESPONSE COMMUNICATIONS SPECIFICATION (Version 1.0)", CEC-500-2009-063, April 2009. Available from: http://drrc.lbl.gov/openadr/pdf/cec-500-2009-063.pdf .

Copyright © 2009 IEEE. All rights reserved 15

IEEE GUIDE FOR Load Side Smart Grid InteroperabilityIEEE Preliminary Draft 0.1

Revision 0.1[SEQ] Examples of some existing smart energy products for the home http://sequentric.com/ .

Copyright © 2009 IEEE. All rights reserved 16