Solar Grid Code
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NTDC Grid Code Addendum No. 2 dated /08.2011 for Grid Integration of PV Solar Projects 1. General (i) This addendum proposed by AEDB, after review and vetting of Grid Code Review Panel of NTDC, has been [here will be written “approved” after approval by NEPRA] by NEPRA. (ii) This addendum is applicable to only Grid Connected PV Solar power plants. (iii) This addendum becomes part of Grid Code with effect from ……./2011 [date of approval], the date of its approval by NEPRA. (iv) All relevant clauses of Grid Code, which are not touched by this addendum, if otherwise applicable, will be applicable to Grid Connected PV Solar Power Projects. (v) All relevant clauses of Grid Code, which can be linked with this addendum, will be taken as amended as per theme included at this addendum. (vi) Any additional ruling provided at this addendum which is not described previously at Grid Code, will now form part of Grid Code with effect from ……/2011 [date of approval], applicable to PV Solar power Projects only. 2. Definitions 2.1 Black Start The procedure for recovery of a power project, without any external resource of Electrical Energy, after a blackout. 2.2 Energy Purchase Agreement The agreement, together with all schedules attached with, by and between the Seller and the Purchaser,
Transcript of Solar Grid Code
NTDC Grid Code Addendum No. 2 dated /08.2011for Grid Integration of PV Solar Projects
1. General
(i) This addendum proposed by AEDB, after review and vetting of Grid Code Review Panel of NTDC, has been [here will be written
“approved” after approval by NEPRA] by NEPRA.
(ii) This addendum is applicable to only Grid Connected PV Solar power plants.
(iii) This addendum becomes part of Grid Code with effect from ……./2011 [date of approval], the date of its approval by NEPRA.
(iv) All relevant clauses of Grid Code, which are not touched by this addendum, if otherwise applicable, will be applicable to Grid Connected PV Solar Power Projects.
(v) All relevant clauses of Grid Code, which can be linked with this addendum, will be taken as amended as per theme included at this addendum.
(vi) Any additional ruling provided at this addendum which is not described previously at Grid Code, will now form part of Grid Code with effect from ……/2011 [date of approval], applicable to PV Solar power Projects only.
2. Definitions
2.1 Black StartThe procedure for recovery of a power project, without any external resource of Electrical Energy, after a blackout.
2.2 Energy Purchase AgreementThe agreement, together with all schedules attached with, by and between the Seller and the Purchaser, for Sale and Purchase of electrical energy from a solar power project.
2.3 Financial ClosureFinancial Closure of a project is the start date of construction work of the project as defined in the Energy Purchase Agreement of that project.
2.4 Grid ConnectedA power project which can deliver Electrical Energy to a grid
network.
2.5 Hybrid Generating System
hasan, 09/15/11,
See 2.14
Sohail, 09/15/11,
Do we really need this definition?
Sohail, 09/15/11,
To be reconciled with another EPA etc.
Sohail, 09/15/11,
To add distributed generation definition.
hasan, 09/15/11,
“Blackout” may be a better choice than “shutdown”
A Generating System in which the power project delivers a mix of power from conventional and renewable power resources in order to overcome deficiencies in one or all resources.
2.6 Islanding OperationOperational mode of a power project in which it stands alone in generating electrical power and feeding a particular load with no other generator running in parallel.
2.7 Low Voltage Ride Through (LVRT)The capability of a Generator to withstand the impact of low voltage dip, for a certain time, to remain connected to Grid without being damaged, in case of external fault conditions.
2.8 Ramp RateUpper limit of a Generator on rate of increase of real power
(MW/min).
2.9 RegulatorNational Electric Power Regulatory Authority (NEPRA).
2.10 Retained VoltageThe value of voltage, normally in percentage of normal rated voltage, which persists at a particular point of a Grid System in case of fault conditions.
2.11 Solar Inverter (Grid – Connected)Device that converts variable Direct Current (DC) output of the Phtovoltaic (PV) modules into the Alternating Current (AC) of Grid frequency with control system capability to deliver both active and reactive power to the three-phase system of the grid matching phases with the sinewave of the grid.
2.12 Stuck Breaker CaseA case of fault condition at a Grid System, in which the fault is not cleared by operation of the concerned breaker, being stuck, and is therefore cleared by the breaker(s) at zones other than faulty zone.
2.13 TermThe total period of Energy Purchase Agreement for Sale and Purchase of electrical energy.
2.14 PV Solar Power ProjectAn installation, with the capability of converting solar light energy into electrical energy through photovoltaic (PV) cells/panels/modules.
hasan, 09/15/11,
Linkage to the grid is defined in 2.4
Sohail, 09/15/11,
What about specifying its linkage to grid?
hasan, 09/15/11,
Yes it is required because the IPP will be bound to abide by the Grid Code Addendum-2 for its Term and any further addendums or amendments in the Grid Code taking place during its Term will not be binding on him
Sohail, 09/15/11,
Is this really required?
hasan, 09/15/11,
It is necessary because this converter has to comply with the frequency of the Grid.
Sohail, 09/15/11,
May this be removed!
hasan, 09/15/11,
To be kept because this abbreviation is used in this document.
Sohail, 09/15/11,
No need!
hasan, 09/15/11,
The definition is reworded
Sohail, 09/15/11,
Pl. compare with the existing definition in the policy! Hybrid conventional vs. alternative or mix alternatives. Worldwide practice.
3. PV Solar Power Technology Requirements
(i) At least 5% of the total installed capacity in the country shall consist of Grid Connected Renewable Energy Projects, including wind power and PV Solar Power Projects.
(ii) After achieving target of overall RE sector to the tune of 5 % of total installed capacity in the country, the criteria will be reviewed in order to avail advantages of advancments in technology.
4. PV Solar Power Plant Data Requirements
A PV Solar Power Project will be required to provide its data applicable to Grid side interface in terms of voltage, current, frequency, active and reactive power, and power quality related issues of harmonics, flicker and unbalance.
5. Black Start and Islanding Operation Requirements
(i) A PV Solar Power Project is exempted from Black Start and Islanding Operation for full Term of Energy Purchase Agreement.
(ii) In case of blackout, PV Solar Power Plants will be required to be disconnected from the Grid. The PV Inverter will have anti-islanding protection built in; it will inject small pulses that are slightly out of phase with the AC electrical system in order to cancel any stray resonances that may be present when the grid shuts down.
6. Synchronization / De-Synchronization
(i) A PV Solar Power Project will manage for
(a) Smooth Synchronization(b) Smooth De-Synchronization
(ii) The above operations, achieved through appropriate equipment, will be without jerk(s).
7. Active Power and Frequency Control
(a) PV Solar Power Plant must be capable of increasing or decreasing of active power output in steps of 10 % of the rated power i.e. at a Ramp Rate of 10% of plant installed capacity per minute
Ejaz Khan, 09/15/11,
This should be subject to appropriate solar conditions.
hasan, 09/15/11,
If you cover this item of provision of data in Grid Code as broad guideline then details can be covered in EPA. However if we don’t mention anything about it in GC Addendum, then for every EPA negotiation we may face an endless debate on this issue. Better keep it as broad guideline.
Sohail, 09/15/11,
supported
Ejaz Khan, 09/15/11,
How will this data be provided and at what frequency and to whom? The EPA itself has detailed requirements for provision of this data. These two should be matched.
Sohail, 09/15/11,
Hassan sb. Agreed to include a provision for exempting distributed generation, less than .5 MW! Further provisions with respect to grid connectivity for DG would be addressed under the respective distribution codes.
hasan, 09/15/11,
5 % of 20000 present installed capacity) is 1000 MW. Even if we go by very optimistic estimates, both wind and solar together will reach this value in next 5 years and then or even before, the cap would be reviewed as per clause 3(II) to increase the cap or put separate caps on solar and wind or remove any cap on solar depending on the experience gained by the Grid Operator. It is prerogative of the Grid Operator to decide how much non-conventional power can it afford to connect to grid without compromising on its stability. PV solar does have impact on system stability because it is a static device with no mechanical inertia and does not provide inertia support in case of disturbance in the system.
AEDB- AJ, 09/15/11,
I would recommend not to apply any caps or limits to solar grid integration. Firstly beacuse the current cap stated here is conflicintg with the cap of wind in the grid addendum for wind where wind energy of 5% of the total installed power capcity is allowed. Secondly and more importantly beacuse high peneration of solar energy into the grid does not have adverse or destablizing effects as wind has. Moreover, the solar energy would not only be intergrated into grid via the IPP projects but a significant amount would be coming form the doemstic and commercial consumers via the net-metering mode, which would not even impact the tariff. Applying any limit or cap on solar would be resstircive to net-metering and other grid connected soalr applications.
(b) There can be 4 or 5 setpoints agreed with NTDC such as 100 %, 70 %, 50 %, 30 % and 0 % which the PV Plant must achieve from any instantaneous operating point in any operation mode.
(c) Both (a) and (b) would be subject to appropriate availability of light at the instant when such variations are required.
8. Reactive Power and Voltage Control
A PV Solar Power Project will manage the following at interconnection point.
(i) Reactive Power Control to maintain the power factor within the range of 0.95 lagging to 0.95 leading, at full active power output, according to Dispatch Instructions/Voltage adjustment requirements.
(ii) The provisions of clause 8(i) will be reviewed after the penetration of Renewable Energy sources to the tune of 5 % of installed capacity in the country.
9. Power Quality Requirements
(i) Power quality parameters, of power output of a PV Solar Power Project, will be governed by relevant IEC Standards such as IEC 60904, 61850 and any other relevant to PV or batteries.
(ii) Monitoring of power quality parameters, for implementation of clause 9(i), will be observed at interconnection point of the PV Solar Power Project.
(iii) For continuous monitoring of power quality parameters, a PV Solar Power Project will install and maintain necessary monitoring equipment, at site.
(iv) Clause 9(i), 9(ii) and 9(iii) will be applicable to the Grid Connected RE power capacity except any related revision of Grid Code.
10. Low Voltage Ride Through (LVRT) Requirements
(i) A PV Solar Power Project must withstand a voltage dip down to 30% Retained Voltage for a duration of at least 100 ms for a normal clearing case and at least for 180 ms in case of Stuck Breaker.
hasan, 09/15/11,
Modified to address the comment of EK28
Ejaz Khan, 09/15/11,
What is the intent behind this?
hasan, 09/15/11,
Modified to address the comment of EK26
Ejaz Khan, 09/15/11,
As above comment.
hasan, 09/15/11,
Same reply as above)
hasan, 09/15/11,
It matches with usual solar grid codes internationally. Sub-Clause (c ) is added to address the comment EK20
Sohail, 09/15/11,
Does this match with solar power operations?
(ii) The PV Solar Power Project will manage active power restoration, after voltage recovery, at a rate of at least 20% of nominal output power per second.
(iii) Provisions of clause 10(i) and 10(ii) apply only to first RE Projects to the tune of 5 % of total power of installed capacity. For any additional Grid Connected PV Solar power capacity, revision of clause 10 will be necessary.
11. Power Generation Capability Forecasting Requirements
(i) Power Generation Capability Forecasting will be managed by a PV Solar Power Project for the tentative estimation but it will not be binding as of conventional power plants.
(ii) The forecasting, as required at 11(i), will be estimated by PV Solar Power Project through
(a) Expected availability of plant during the period of forecast.
(b) Predicted value of irradiation at site based upon analysis of historic irradiation data available.
(iii) The forecasting, as required at 11(i), will be on the basis of total PV Solar Power Project and break-up for each solar module will not be required.
12. Limitation on Total Grid Connected PV Solar Power Capacity
(i) Initially Grid Integration of Renewable Energy Projects, including wind power and PV Solar, to the tune of 5 % of total available power of installed capacity in the country, will be permitted. The first come first serve criteria will be based on the financial closure of the projects under consideration.
(ii) After achieving the target as per clause 12 (i), further addition of RE power to Grid will depend on
(a) Data collected on operational behavior of first Grid Connected RE power capacity.
(b) Power quality improvement with advancement of technology.
(c) The relevant methodologies successfully adopted at global level to facilitate Islanding Operation of Hybrid Generating Systems.
(d) Increase in installed capacity of Grid Connected conventional power plants.
Sohail, 09/15/11,
To be shifted to 3 above.
hasan, 09/15/11,
It is not a legal matter. It is a technical matter and all Grid Operator all over the world decide the limit of RE power projects depending on system stability analyzed technically.
Ejaz Khan, 09/15/11,
This is not valid legally. Capacity addition policies should not be controlled through Grid Code but through express policy decisions by the Government of Pakistan. Grid Code is only an operational document.
Ejaz Khan, 09/15/11,
As above.
Sohail, 09/15/11,
Redundant!
hasan, 09/15/11,
Reply same as above)
Ejaz Khan, 09/15/11,
AS above.
(iii) In order to enable the Regulator to keep the total Grid Connected RE power capacity within allowable limit, no RE power plant, , will be connected to grid except after prior permission by NEPRA.
Ejaz Khan, 09/15/11,
As above.
hasan, 09/15/11,
NTDC will insist to keep it and I believe that it should be kept.
Sohail, 09/15/11,
No need, obvious!
Sohail, 09/15/11,
Removed during meeting on Sept. 15,
