nerc nigeria gridcode v0l1

8/12/2019 NERC Nigeria GridCode V0l1

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THE GRID CODEFOR THE

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NIGERI ELECTRICITY TR NSMISSIONSYSTEM

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GRI ODEINDEX

PART 1: GENERAL CONDITIONS GC)1.

2.

3.

4

SECTION : BACKGROUND1.1.1 21 31415

TitleNewA rrangement or the Nigerian E lectricity SectorThe GridCodeApplicatiO n of he GridCodeRole of he TG\l

SECTION: OR GANISATION ND OBJECTIVES21 Oijective

Uiforeseen cirmmstances2 3 E iforcement24 DefinitiO ns25 IntetpretatiO n26 Derogations7 Hierarchy

28 Data andNotices29 i t i ~ n s s

SECTION: REviEW PROCESS ND CODE DISPUTES3133 3

ReviewPanelGrid Code AmendmentsDistribution CodeDisputes

SECTION : MONITORING, TESTING ND INvESTI GATIONS414434445

GeneralMO nitoringTestingInvestigationsCO nsequencesofMonitoring, Testing andImestigation

PART 2: PL NNING CODE PC)1.

2.

SECTION : PURPOSE ND SCOPE1.1.1 21 3

OijectivesPutposeSCOPE

SECTION : Lo D FORECAST21 Oijective

Long term Demand Forecast

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4.

SECTION: EXPANSI ON PLANNING313 23 3

Planning standardsLong Term ExpansiO'n PlanUser involvement

SECTION: D ATA REQUIREMENI S FORL ONGTERM PLANNING41 Itif(Jr JiatiO'n Required4 2 Standard Planning Data4 3 Generating Unit Data44 DemandandActive Energy Data45 DetailedPlanning Data46 Transient Over-voltageAssessment Data4 7 User's ProtediO'n Data48 Netlwrk Data

PART 3: CONNECTION CONDITIONS

1.

2.

SECTION: PuRPOSE AND SCOPE111 21 3

OijectivePurposeScope

SECTION: T RANSMISSION SYSTEM PERFORMANCE CHARACTERISTICS21 Frequen9' and Voltage2 2 Voltage PerturbatiO'ns

3. SECTION: CONNECTION PROCESS313 23 3

ApplicatiO'n for connectionProcess of he applicationCO'nnection Agreement

GridCode -Version 01212121232424253033343939424

4 SECTION:TECHNICAL CRITBRIA FOR PLANTAND APARATUS AT IHB CONNECTION POINT

4343434445454648489

525353535455555660

414 24 3444546

GenerolSCADA Meawrement andData ExchangeTelecommunication InstallatiO'nsPower System controlProtection Criteria and MeteringAdditional Requirementsfor Power StatiO'ns

PART 4: OPERATION CODE

1. SECTION : PuRPOSE AND SCOPE11 Oijective1 2 Scope

2. SECTION: POWER SYS EM CONTROL212 2

OijectiveGenerol

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GridCode -Version 012 3 Power System ControlActions 6224 Notification to all Users 6325 Control under ault or emetgenf) conditions 6326 De-energisation o plant 642 7 Operatingprocedures including Fault Reporting 64

3 SECTION : FREQUENCY CONTROL AND OPERATING REsERVE 6631 Oijective 663 2 Generol 663 3 Frequef) limits 6634 Frequenf) Control 6735 Components o Operoting Reserve 6736 Operoting ReservepolifY 683 7 Amounto Operating Reserve 7038 Operating Reserve Procurement 70

4 SECTION :VOLTAGE CONTROL 7441 Oijective 744 2 Generol 744 3 Voltage Control 7444 Voltage Controlpolify 7545 Voltage Control methods 7546 Voltage Control during emetgencies 754 7 Provision o voltage control 76

5 SECTION : BLACKSTART 7851 Oijective 785 2 Generol 785 3 Ancillary Service 7854 Requirements 78

6 SECTION: EMERGENCY OPERATION AND RESTORATION 861 Oijective 806 2 Generol 806 3 E mergef) operation 8164 Restoration o supp J 8265 Back-up Control Centre 8366 E mergenf) co-crdination acility 836 7 Under Frequef) Load shedding 84

7 SECTION:OPERATIONAL PLANNING 8671 Oijective 867 2 Generol 867 3 Functions o he OperationalPlanning staff 8774 Data required or Medium Term and operationalPlanning 88

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GridCode -Version 017.5. d t ~ a i Demand CO'ntroidata 907.6. CO'nnectitms 907 7. Changes tO ' formation Alreat J Stpplied 917.8. Timing and t ~ b l i c a t i O n 92

8. SECTION: INFORMATION ExCHANGE 938.1. Oijective 938 2. Generoi 938.3. Req11irement to notify 938.4. NO'tijicatiO n o an operotion 938.5. Form o notfftcation o an operatiO'n 948.6. Recr;rdingo an operation 948 7. Timing in respect o an operation 948.8. NO'tijicatiO n o eventr 958.9. Form o notfftcation o an event 958.10. Provision o 11rther i' fO'roJation 958.11 . Recr;rdingo an event 958.12. Timing in respect o an e n t 958.13 . OperatiO'naJ cr;mm11nicatiO n and data retention 968.14 . CO'ntact JocatiO ns 968.15. Comm11nication facilities 988.16. SllfJervisory cr;ntroi and data acq11isition SCADA) 988.17. Ctm1pllfer eq11ipment 998.18. Telephtme/ Facsimile 998.19. Access and seCIIrity 998.20. Time standards 1008.21 . Comm11nication between the Users 1008.22. Data andnO tices 1008.23. Data refentiO'n 101

9. SECTION: SCHEDULING AND DISPATCH 1029.1. Oijective 1029 2. Generoi 1029.3. Data andProcess 1029.4. Dispatch Sched11ling 1039.5. Generotion Dispatch 105

10. SECTION: 0UfAGB COORDINATION 11110.1. Oijective 11110.2. Generoi 11110.3. Outage sched11ling 11110.4 . Changes tO the cr;mmitted 011tage sched11lingprogram 11310.5. Other i' fO'roJation to be nO'tifted 113



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Grid ode -Version 0111 SECTION: REliABILITYMEAsURES 115

11 1 Oijective 11511 2 Generol 11511 3 Applicable Reliability Criteria 11511 4 Reliability Indicators 11611 5 Reporting 116

12 SECTION:OPERATIONALTESTING ON THB NE WORK 117121 Oijective 117122 Generol 117123 Tests Required J y TSP or S) Stem Operator 11712 4 Tests required J y User(s) 118125 E val110tionofProposed Operational Tests 119126 Approval or OperationalTesting 11912 7 SchedulingofOperational Tests 120128 Dispatching ofOperational Tests 121129 Test Reporting 1221210 Disputes 122

13 SECTION: SAFETYAND COORDINATION 123131 Oijective 12313 2 GEneral 123133 Intetpretation 123134 Procedure 124135 RecordofNetwork Safety Precautions RNSP) 125136 Safety Precautions on High Voltage Equipment 126



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PART 1: GENER L CONDITIONS GC)1 SECTION: B CKGROUND1 1 TITLE

1.1.1. The Grid Code and guidelines shall be called the Grid Code for the ElectricityIndustry ofNigeria (d1e Code )1.2. NEW RR NGEMENT FOR THE NIGERI N

ELECTRICITY SECTOR1.2.1. The Electric Power Sector Reform Act, 2005 (henceford1 referred to as d1e Act)gave legal backing to the unbundling of the Nigeria Power Sector. The Act stipulates thefunctional unbundling of d1e Generation, Transmission and Distribution Sectors.1.2.2. Pursuant to Sections 8, 65 and 66 of d1e Act, a Transmission and SystemOperating Company (TCN) shall be established and licence to perform d1e functions oftransmission and sys tem operations of the High Voltage network of the Nigerianelectricity industry. In addition, T N shall be responsible for overseeing marketoperations involving d1e trading ofwholesale energy amongst market Users.

1.3. THE GRID CODE1.3.1. The Grid Code contains d1e day-to-day operating procedures and principlesgoverning the development, maintenance and operation of an effective, \vell coordinated and economic Transmission System for the electricity sector in Nigeria.1.3.2. The code is designed to :

(a) Facilitate an efficient production and supply of electricity for all Usersof d1e Transmission System and T N itself, \.vid10ut any act ofdiscrimination between Users or class ofUsers.

b) Facilitate competition in d1e generation and supply of electricity in d1ecountry.1.3.3. For complete understanding of the operation of d1e Nigeria Electricity industrypost -deregulation, this document have to be read in conjunction with the Market Rules,Distribution Code and other documents relating to od1er operational aspects of d1eindustry.

1.4. APPLICATION OF THE GRID CODE1.4.1. The Grid Code shall apply to T Nand Users of the Transmission System. T Nshall be responsible for implementation of the Grid Code. All Users shall comply withthe Grid Code and assist T Nin dlis regard. Users must provide all d1e required

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information and reasonable rights of access, serviCe and facilities necessaq forimplementation of the Grid Code.(a) If any User has any difficulty in complying with any of the provisions

of the Grid Code, the User shall immediately, without delay, inform thesame to the Nigerian Electricity Regulatory Commission and T N, andshall remedy his non-compliance prompt ly.

b) Consistent failure in compliance with the Grid Code may lead todisconnectionof the Users plant, Equipment or Apparatus.

(c) The operation of the Grid Code shall be reviewed regularly by the GridCode Review Panel in accordance with tl1e provisions of the relevantSections of the Code.

15 ROLE OF THE T N

1.5.1. T Nshall perform two different group of functions in relation to network andsystem operation activities:(a) As Transmission Service Provider TSP):

(i) admit Users in accordance witl1 the Market Rules who satisfy therequirements for admission;

(ii) evaluate and accept grid connections;(iii) ensure proper metering at all Connection Points;(iv) obtain necessary information from Users of tl1e Transmission Networkto enable it perform adequate planning operations and development ofthe Transmission Network.b) As System Operator:(i) dispatch Generating Units in accordance witl1 tlus Code at least cost, onthe basis ofNominations by Generators;(ii) procure Ancillary Services and recover the costs of procuring AncillaryServices;(iii) handle Power System emergencies and restore the Power System;(iv) perform Demand forecasting;v) co-ordinate Generation and Transmission Outages;

(vi) supenrise compliance witl1, and enforce, the Grid Code and MarketRules.vii) test and monitor of Users equipment to ensure tl1eir compliance withthe Grid Code.

) report of scheduled and planned actions and unexpected occurrencessuch as faults to network Users and the Regulator

(L {) procedures for conducting system tests pertaining to the network.

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2 SECTION ORGANISATION AND OBJECTIVES

2 1 OBJECTIVE

2.1.1. The objective of these General Conditions are,a) To establish the conditions applicable to all the Grid Code and to theextent possible, ensure d1at the various parts and sections of the Grid Codework together for d1e benefit of d1e TSP, System Operator and all Users,and apply consistently to all Users;

b) To provide d1e principles and procedures for the development andapplication of d1e Grid Code.c) To establish requirements for monitoring, testing and investigation onwhether Users are operating within their design, operating and connectionrequirements, as specified in this Code, Grid Connection Agreements,

Ancilla1y Services Agreements or any od1er relevant Agreements betweenUsers and the TCN.

2 2 UNFORESEEN CIRCUMSTANCES2.2.1. The Grid Code contains procedures for d1e management of day to day technicalsituations on the Transmission Network, taking into account a wide range of operationalconditions likely to be encountered under both normal and abnormal conditions.2.2.2. The Grid Code cannot predict and address all d1e possible operating conditions.Users must d1erefore understand and accept that d1e TCN, in such unforeseencircumstances, may be required to act decisively to discharge its obligations under itsLicense conditions), widlin the following general principles and priorities.a) As first priority, preserve or restore d1e integrity of d1e TransmissionSys tem, including the avoidance of breakdown, separation or collapse total

or partial).b) Compliance by the System Operator with d1e Electric PO\ver SectorReform Act, conditions in its System Operator Licence, and d1e Grid

Code.c) Preserve d1e safety of equipment, to prevent damage to Plant and/ orApparatus, and public safety to prevent personal injmy.

Users shall provide such reasonable cooperation and assistance as TCN may requirein such circumstances.

2.2.3. In case of an unforeseen circumstance d1at can not be resolved wid1 d1e generalprinciples defined in d1e previous condition, the System Operator shall act according tothe following

a) The application of a policy aimed at the equitable sharing amongstUsers of any temporary restriction d1at might be necessary in exceptionalcircumstances, and

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2.2.4. If circwnstances not envisaged by the provisions of d1e Grid Code should arise,the System Operator shall, to d1e extent reasonably practicable in d1e circumstances,consult prompdy and in good faith with d1e Panel or all affected Users in an effort toreach agreement as to what should be done. If agreement between the System Operatorand the Panel or affected Users cannot be reached in d1e time available, the SystemOperator shall determine what shall be done in accordance to dus Grid Code2.2.5. The System Operator shall prompdy refer any unforeseen circumstanceidentified, together with the determinations and interpretations made, to d1e Grid CodeReview Panel for consideration.2.2.6. E ach User shall comply wid1 all instmctions given to it by the System Operatorfollowing a determination for an unforeseen circwnstance or a difference ininterpretation, provided d1at such instmctions are consistent wid1 d1e technicalcharacteristics of d1e User s System and d1e principles established in the Grid Code, anddo not endanger d1e safety of its equipment or staff.2.2.7. Users should note d1at d1e provisions of the Grid Code may be suspended inwhole or in part during a Security Period as more particularly provided for in d1e FuelSecurity Code , or in accordance with a ivil Emergency Direction issued under a ivilEmergency directive by appropriate authority.

2.3. ENFORCEMENT2.3.1. The Electric Power Sector Reform Act of 2005 assigns to the Nigeria ElectricityRegulatory Commission NERC) d1e authority to establish the appropriate technicalcodes and manuals that may be required for the safe, reliable and efficient operation ofthe sys tem. Within such powers, the NERC has d1e aud10rity to establish the initi l GridCode and to approve amendments from time to time as reviewed by d1e TCN andaffected Users.2.3.2. The provisions of dus Code shall be enforced by d1e System Operator inaccordance with the Rule 46 of the Market Rules, guidelines from the NigerianElectricity Regulatory Commission, Grid Connection Agreement and relevant industryRules and Regulation.

2 4 DEFINITIONS

2.4.1. Capitalised words and expressions used in dlis Code, unless the contextotherwise requires, shall have the meaning assigned to d1em in Appenci.L { 1.

2 5 INTERPRET TION

2.5.1. Indus Code, unless the context othe1wise requires:(a) a reference to a particular Section, subsection, or Appenci.L { is to asection or subsection of, or Appenci.L { to, dlis Code;(b) a reference in a particular Condition or Appendix to a paragraph is to aparagraph of d1at section or Appenci.L {;



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(c) the table of contents and Section and subsection headings are forconvenience only and shall be ignored in construing this Code;(d) references to the masculine include the feminine and references n the

singular include references in the plural;(e) ''N means Naira;(f the word include shall be construed without limitation;g) a reference to a person includes any individual, partnership, firm,company, c01poration (statutory or otherwise), joint venture, trust,

association, organisation or other entity, n each case whether or not havingseparate legal personality;(h) a reference to applicable law shall be construed, at the particular time,

as including a reference to any modification, extension, re-enactment orreplacement thereof then in force;i) a derivative term of any defined or interpreted term or expression shall

be construed in accordance with the relevant definition or interpretation;G a reference to another agreement or any deed or other instrument shallbe construed as a reference to tl1at otl1er agreement, deed or otl1er

instrument, as the same may have been, or may from time to time be,modified; andk) In writing means typewriting, printing, lithography, electronic mail,facsimile and otl1er modes of reproducing words n a legible and no ntransitory form.

2.6. DEROG TIONS2.6.1. If a User finds that it is, or w ll be, unable to comply \.vith any provision of dusCode, tl1en the User shall, wid10ut delay, rep01t such no n-compliance to tl1e SystemOperator and tl1e Nigerian Electricity Regulat01y Commission (NERC) and shall makesuch reasonable efforts as are required to remedy such non-compliance as soon as isreasonably practicable.2.6.2. 'When the non compliance described n the previous Condition arises upon theissuance of dus Grid Code, or a revision to tlus Grid Code relating to Eqtupmentalready connected to the Transmission System or Equipment approved to be connectedto the Transmission System where the User has commenced the procurement or worksprior to tl1e issuance of this Grid Code or the revision to this Grid Code, and the Userbelieves either tl1at it would be unreasonable (including on tl1e grounds of cost andtechnical considerations) to remedy such non-compliance or tl1at it should be granted anextended period to remedy such non-compliance, the User shall promptly submit to tl1eSystem Operator a request for derogation from such provision in accordance witl1 thisSection. The burden of proof shall rest with tl1e User to show good reason why it cannotcomply.2.6.3. If TCN finds tl1at it is, or w ll be, unable to comply with any provision of dusGrid Code, tl1en it shall, without delay, report such non-compliance to the NERC and



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shall make such reasonable efforts as are required to remedy such non-compliance assoon as is reasonably practicable.2.6.4. when the non compliance described n section 2.6.3 arises upon d1e issuance ofthis Grid Code, or a revision to this Grid Code relating to Equipment already connectedto the Transmission System or Equipment approved to be connected to theTransmission System where T N has commenced d1e procurement or works prior tothe issuance of dlis Grid Code or the revision to dlis Grid Code, and T N believeseither that it would be unreasonable (including on the grounds of cost and technicalconsiderations) to remedy such no n-compliance or that it should be granted an extendedperiod to remedy such non-compliance, T N shall prompdy submit to d1e NERC arequest for derogation from such provision in accordance wid1 this Section. The burdenof proof shall rest wid1 TCN, to show good reason why it cannot comply.2.6.5. A request for derogation from any provision of dlis Grid Code shall contain:

(a) the detail of the Equipment and Connection oint in respect of whichderogation is sought and i relevant, d1e nature and extent of no ncompliance;b) the provision of this Grid Code wid1 which d1e T N or User d1atrequests the derogation is, or will be, unable to comply;

(c) the reason for d1e non-compliance; and(d) the remedial actions and d1e date by wllich compliance could beachieved lf remedy of d1e non-compliance is possible).

2.6.6. Every SL { months, d1e System Operator shall report to the NER :(a) the list of derogations requested during the past SL { (6) months,

including requests by d1e TCN, and the status of each request;b) the list of approved derogations during d1e past six (6) mond1sindicating type of derogation and party; and

(c) for each approved derogation, the progress of remedial actions nachieving compliance.2.6.7. On receipt of any request for derogation, d1e System Operator or d1e NERC, asapplicable, shall prompdy consider such a request provided that the System Operator orthe NER considers that d1e grounds for the derogation are reasonable. n itsconsideration of a derogation request, the System Operator or d1e NER , as applicable,may contact the User or System Operator, to obtain clarifications of the request orrequest additional information or to discuss changes to the request, and review possibleremedial actions to achieve compliance as soon as reasonably practicable.2.6.8. The System Operator shall:

(a) keep a register of all derogations wllicl1 have been granted, identifyingthe name of d1e User in respect of \vhom d1e derogation has been granted,the relevant provision of this Grid Code and d1e period of d1e derogation;and

b) on request from d1e NER or any User, provide a copy of such registerof derogations .



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2.6.9. The NERC shall keep a register of all derogations d1at have been granted to d1eTCN identifying the relevant provision of dus Grid Code and d1e period of thederogation.2.6.10. The NERC may initiate on ts own initiative or at the request of d1e SystemOperator, or in view of a User complaint, a review of any existing derogations, and anyderogations under consideration where a relevant and material change in circumstancehas occurred.

2.7. HIER RCHY2.7 1. In the event of any inconsistency between dlis Grid Code and d1e ElectricPower Sector Reform Act, or d1e license of a the TSP or the System Operator or aLicensee that s a User, the ESPR Act 2005 shall prevail to d1e extent of suchinconsistency.2.7 2. Nothing in dlls Grid Code s intended to or shall derogate from a Licensee anylicense obligation.2.7.3. If any provision of dlis Grid Code should be found to be unlawful or wholly orpartially invalid for any reason, the validity of all remaining provisions of dus Grid Codeshall not be affected.2.7.4. If part of a provision of dlls Grid Code s found to be unlawful or invalid butthe rest of such provision would remain valid if part of d1e wording were deleted, d1eprovision shall apply wid1 such minimum modification as may be:

(a) necessru.y to make it valid ru 1d effective; andb) most closely achieves d1e result of d1e original wording but wid1out

affecting the meaning or validity of u 1y od1er provision of dlis Grid Code.2.7.5. In d1e event of any conflict between d1e provisions of dlls Grid Code and anycontract, agreement or arrangement between TCN and a User, d1e provisions of dlisGrid Code shall prevail unless dlls Grid Code expressly provides od1envise, providedthat in d1e case of Connection Agreements with Users signed prior to d1e approval ofdlls Grid Code, the conditions in such agreement shall prevail unless

(a) the pru.ties agree an amendments: orb) the User registers a no n-compliance situation that negatively affects d1esecurity of the T ransmission System, in wluch case d1e User must accept

the necessary amendments to ensure full compliance wid1 tlus Grid Code,except for any derogation.

2.8. D T NDNOTICES2.8.1. For d1e purposes of tlus Code, Business Day'' means a day od1er tl1an:

(a) a Saturday or a Sunday; orb) a public holiday in Nigeria;

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2.8.3. Any notice required to be given by tllis Grid Code shall be deemed to have beengiven or received:(a) if sent by hand, at the time of delive1y;b)

(c)if sent by post, from and to any address within Nigeria, [four (4)

Business Days] after posting unless otherwise proven; orif sent by facsimile, subject to confirmation of uninterruptedtransmission report, or by e-mail, [one hour] after being sent, provided thatany transmission sent after [17:00 hours] on any day shall be deemed tohave been received at [08: hours] on tl1e following Business Day unlessthe contra1y is shown to be the case.

2.9. EFFE TIVENESS2.9.1. The provisions of tllls Code shall come into effect upon the satisfaction orfulfilment of the events and matters set out or referred to in Appendix 2 (tl1eConditions Precedent ),as declared by tl1e Commission.

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3. SECTION REVIEW PROCESS ND CODE DISPUTES3.1. REVIEW P NEL

3.1.1. A Grid Code Review Panel G RP) shall be formed pursuant to Rule 42 of d1eMarket Rules. This Panel will be in charge of dlls Grid Code review and amendment.3.2. MENDMENTS TO GRID CODE

3.2.1. This Code may be amended in accordance with dle provisions of Rule 45 of d1eMarket Rules3.3. DISPUTES ON THE GRID CODE

3.3.1. Any Dispute relating to, arising out or in connection wid1 dlls Code between:a) a User and dle TSP;b) a User and dle System Operatorc) a person who applies to be a User and d1e TSP; andd) between Users,

shall be resolved in accordance widl dle provisions contained in Rule 43 of d1eMarket Rules.



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4 SECTION: MONITORING TESTING ANDINVESTIGATIONS

4 1 GENERAL4.1.1. he System Operator or the TSP, as correspond, will need to carry out certainmonitoring, testing and investigation in respect of d1e performance and characteristics ofGeneration and Load plant in order to discharge its responsibilities in respect of the safe,secure and economic operation of the Transmission System and in respect ofGeneration Dispatch.4.1.2. In order to achieve d1e primary objectives, procedures need to be established forthe monitoring, testing and investigation for each of the following

a) Whed1er centrally Dispatched Generating Units comply with DispatchInstructions;b) \ ~ h e d e r Generators are in compliance wid1 registered Availability,Ancillary Services capabilities, operating characteristics and any other data

required to be registered by those Generators;c) Whed1er power quality of Users conforms to the standards and limitsagreed upon between the affected parties, wid1 respect to the minimum

and m ~ C i m u m fault levels, harmonic current injected limits, harmonicvoltage contributions, short-term and long-term voltage Flicker, voltageunbalance, d1e number and the duration and severity of voltagedepressions; and

d) Whed1er Users are in compliance with protection requirements andprotection settings, Grid Connection Agreements, Ancillary ServicesAgreements and other relevant support agreements between Users and theSystem Operator or d1e TSP, as correspond .

4 2 MONITORING4.2.1. Time

Monitoring may be carried out at any time by d1e System Operator or TSP, ascorrespond, and may result, without the application of furd1er testing, in d1eevaluation by d1e System Operator or TSP of User/ Participant non-compliance.

4.2.2. PeriodMonitoring may be continuous for a specified or unspecified period and shall becarried out by monitoring, data recording and analysis. t shall not require advancenotice from d1e System Operator or TSP to Users.

4.2.3. Recording and analysis system

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\Xlhere a data recording and analysis system is used, the System Operator shallinform d1e Participant d1at any instrument is being used and, on request from d1eParticipant, shall make available to the Participant information in respect of d1e datarecording and analysis system.

4.2.4. DisputesDisputes shall be handled according to Rules and Regulations of the GCRP.

4.2.5. Performance parametersPerformance parameters shall be defined according to Rule 6.1 of the MarketRules.

4.2.6. Monitoring systems and proceduresThe systems and procedures shall be laid out as defined in the Market Rules.

4.3. STNG4.3.1. System Operator s or TSPs right to testing

System Operator s or TSPs m ay, from time to time, carry out tests to verify that aParticipant is complying wid1 its connection conditions and registered operatingcharacteristics in d1e Registered Information.The System Operator may:

(a) Induce controlled Power System Frequency of voltage conditions orvariations for d1e purpose of determining that the Generating Unit sresponse is in accordance with its registered Availability, Ancillary Servicecapabilities and operating characteristics, and

b) Having given three (3) business days notice, or less where agreed, senda representative to the Participant s site to verify by testing in accordancewid1 d1e test procedures specified, d1at the Participant is in compliancewid1 its registered values.

4.3.2. Dispatch InstructionTests shall be carried out to a Dispatch Instruction from the System Operator.A test may require d1e Participant to carry out specific actions in response to aDispatch Instruction.

4.3.3. Site attendanceA System Operator or TSP representative shall be allowed at Participant sites inorder to carry out tests in accordance with agreed or generic testing procedures.

4.3.4. ResultsThe results of a test may be derived from the monitoring of performance during d1etest.



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4.3.5. Subcontracting of testing workIf the System Operator or TS subcontracts testing work on a Participant s site,d1en d1e Participant and the System Operator or TS shall be in agreement on theselection of a suitable subcontractor.

[Note:This provision could be left to the Grid Connection Agreement.]4.3.6 Confidentiality

Confidentiality according to applicable Market Rules shall be adhered to.4 4 INVESTIGAT IONS

4.4.1 Refer to applicable (Rules 44.2 in the) Market Rules for details on investigations .45 CONSEQUENCES OF MON ITORING TESTIN G AND

INVESTIGAT ION4.5.1 Refer to applicable indusa:y rules and regulation (e.g. Rule 44 in the MarketRules) for issues surrounding enforcement of these Conditions.



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PART 2: PLANNING CODE PC)1 SECTION PURPOSE AND SCOPE

1 1 OBJECTIVES1.1.1. The objectives of this Plarming Code are:

(a) To provide the guidelines and address the requirements for the SystemOperator to perform long-term expansion planning of d1e NigerianTransmission System.

b) To specify the conditions and guidelines for the Users to provideinformation to the TSP or the System Operator in order that planning anddevelopment of the Nigerian Transmission Network can be undertaken inaccordance with relevant Licence Standards.

(c) To Specify Licence Standards which will be used in the planning anddevelopment of the Nigeria Transmission Network.

(d) To specify d1e information required by the System Operator fromUsers in respect of capability of gas-fired generating units to run usingalternative fuels and mothballed Generating plants.

(e) To promote interaction between TSP and Users in respect of anyproposed development on the network or Users system that might impacton the performance of d1e Nigeria Transmission Network orinterconnection to d1e network

1.2. PURPOSE1.2.1. The Transmission System expansion planning will cater for the connection ofnew Load/ Generation to d1e Transmission System. It w ll ensure d1at d1e impact ofthese connections can be handled by the existing Transmission System or, i not, t willidentify d1e need for d1e required expansion. The planning and development of d1eTransmission System shall be in accordance with the Transmission Planning Criteria andrelevant standards applicable in Nigeria.1.2.2. Reasons for development: The development of the Transmission System,involving its reinforcement or extension, will occur for a number of reasons including,but not limited to:

(a) A development on a Users System (e.g. Distribution Company) alreadyconnected to the Transmission System;b) The introduction of a new substation or d1e modification of an existing

substation between a User s System and the Transmission System;(c) Changing requirements for electricity transmission facilities due to

changes in factors such as D emand, Generation, technology Reliabilityrequirements, and/ or environmental requirements; and

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(d) A combination of more d1an one of the above-mentioneddevelopments.1.2.3. Work involved: The reinforcement or extension of the Transmission Systemmay involve works:

(a) At a new or existing substation where the Users Plant and/ orApparatus is connected to the Transmission System;b) On new or existing Transmission lines or other facilities which join d1atsubstation to the remainder of the Transmission System; and

(c) On new or existing Transmission lines or od1er facilities at or betweenpoints remote from that substation.

1.2.4. Timing The time required for d1e planning and development of d1eTransmission System will depend on the type and extent of the necessaq reinforcementand/ or extension work. The time required for obtaining planning permission andservitudes, including any associated hearings, and the degree of complexity nundertaking d1e new work while maintaining satisfactoq security and Quality of Supplyon the existing Transmission System.

13 SCOPE

1.3.1. The Planning Code apply to the System Operator, TSP and to Users of d1eTransmission System which in this Part of the Code are:(a) Power Stations;b) Distributors;

(c) Interconnected Parties;(d) Customers connected to d1e Transmission System.

2 SECTION LOAD FORECAST

21 OBJECTIVE

2.1.1. The objective of dus section is to specify d1e Generation and Demand Forecaststhe System Operator has to generate for both short to medium term planning andexpanswn purposes.

22 LON G TERM DEMAND FORECAST2.2.1. Timing and publication: System Operator shall create a new long term (15 years)Demand Forecast for the Transmission Network, at least once every 3 years.

Tllis long term Demand Forecast ,shall be updated yearly, and shall form part of d1ereport on long term expansion planning to be supplied to the Commission pursuantto subsection 3.2.7.



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2.2.2. emand Forecasts factors: The System Operator shall take the followingfactors into account when conducting long term Demand Forecasting:a) Historical D emand data;b) Current and anticipated future land use;c) Population and demographic forecasts;d) Economic growth rates; ande) Other information supplied by Users.

2.2.3. D emand Forecast methodology: System Opera tor shall use a geographical basedDemand Forecast med1odology based on the factors .in subsection 2.2.2 to produceunbiased forecasts of d1e Transmission Network D emand .into the future.

The med1odology shall allow System Operator to perform sensitivity analysis todetermine an optimistic, realistic or pessimistic long term D emand Forecast.

3. SECTION EXPANSION PLANNING3.1. PLANNING STANDARDS

3.1.1. T ransmission Planning Criteria: The System Operator, .in consultation wid1 d1eTSP shall develop comprehensive Transmission Planning Criteria to guide the expansionplanning of the T ransmission System. The Transmission Planning Criteria shall beapproved by d1e Commission.3.1.2. The System Opera tor shall apply the T ransmission Planning Criteria and relevantstandards n d1e planning and development of d1e T ransmission System.

3.2. LONG TERM EXPANSION PLAN3.2.1. Long term Demand Forecast

T he System Operator shall use the long term 10 years) D emand Forecast for d1eT ransmission System, pursuant to section 2.2, as input for long term expansionplanning.

3.2.2. RefurbishmentT he System Operator shall perform refurbishment audits on the eXIstmgT ransmission System n order to determine the remaining useful life of d1eT ransmission System components.T he System Operator shall generate a refurbishment plan to replace ageing anddamaged Equipment.

3.2.3. Analyse current networkT he System Operator shall analyse and document d1e current Transmission Systemadequacy n accordance with Section 14.5.

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3.2.4. Expansion alternativesThe System Operator in collaboration wid1 the TSP shall hold workshops withstakeholders to determine possible alternatives to address d1e combination of d1efollowing inputs:

a) Long term Demand Forecast;(b) Refurbishment needs; andc) Current Transmission System performance.

3.2.5. Analyse alternativesThe System Operator in collaboration with the TSP shall evaluate the altemativesdetermined pursuant to subsection 3.2.4 for at least five, ten, and fifteen years intod1e future.At least the following analysis shall be performed:

a) Load flow analysis;(b) Fault level calculations;c) Stability studies;d) Reliability studies; ande) Financial analysis.

3.2.6. Based in the analysis performed pursuant subsection 3.2.5 d1e System Operatorshall develop a financially feasible least cost expansion plan that meets the approvedplanning standards.3.2.7. Long-term expansion plan report

The System Operator shall document the long-term ten year expansion plan in areport evety year. This repor t shall include at least the following sections:

a) Long-term Demand Forecast;(b) Long-term Generation Adequacy Forecast;c) Long-term Transmission Network Adequacy Forecast;d) Long-term zonal Supply and Demand 1v argine) Long-term Statutoty outage plan for transmission infrastructuref Long-term Refurbishment plan;

(g) Alternatives Identification and Analysis);h) Capital program; andi) Financial motivation.

The Commission shall circulate dlis report to all Users for comments. TheCommission will approve the long-term expansion plan once it is satisfied that d1eSystem Operator has taken all relevant comments into account.

3.2.8. Approval

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The TS shall be committed to implement the projects listed in d1e long-termexpansion plan (and only d1ese projects) after d1e Commission has approved d1ereport.

3.3. US R INVOLV M NT3.3.1. User s data

The System Operator shall require Users to provide data and information (asdetailed in Appendices 6 and T on a regular basis, in order for the System Operatorto undertake the planning and development of the Transmission System inaccordance with international standards. Information received for this purpose shallbe treated as Transmission System planning data.

3.3.2. Additional dataThe System Operator or the TS shall require additional data or information from aUser when d1e System Operator considers it necessary. The User shall submit theinformation to the System Operator without delay. Such information may berequired so d1at d1e System Operator can:

(a) Plan and develop the Transmission System m accordance wid1 d1erelevant standardsb) Monitor Power System performance and project Power Systemperformance

(c) Fulfil its statutory or regulatory obligations.3.3.3. Plant modification

In planning for the development of d1e Transmission System, d1e System Operatoror the TS may require an individual User, or group of Users, to modify or installnew plant or apparatus, where the System Operator can reasonably show that it ispmdent or necessary to do so . f d1e work is to be a significant benefit to d1eUser(s), the expenses shall be borne by d1e User(s) otherwise by d1e TSP.

3.3.4. ObjectionThe User(s) may object on grounds that to modify or install new plant or apparatusas required, in accordance with Good Utility Practice, would be technically orfinancially infeasible. Tllis may include, but shall not be limited to, for example, d1einstallation of Power System Stabilisers.

3.3.5. Closing downTl1e User(s) shall give the System Operator at least 24 calendar mond1s notice if d1eUser(s) plans to close down, retire or withdraw from service any of its GeneratingUnit(s), Equipment or Apparatus. It also applies if User(s) ceases to maintain andkeep available any Generating Units wid1 registered capacity greater than 10 M\ V fordispatching.



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4 SECTION DATA REQU IREMENTS FOR LONG TERMPLANNIN G

41 INFORMATION REQU IRED4.1.1. In order to develop the Long Term Expansion Plan, the System Operator shalluse the guidelines and data requirements indicated in Appendices 5, 6. 7 to specify d1etechnical, design criteria and procedures to be applied in the planning and developmentof d1e Nigeria Transmission Network. This information shall be taken into account byUsers, when the planning and develop their own plant and equipment connected to d1enetwork.4.1.2. For Network Planning, User information required as stipulated inAppendices 5,6, 7 includes data on:

(a) Standard Planning Data(b) Detail Planning Data(c) Network Planning data (Forecast and Registered)(d) Connection Planning D ata

4.1.3. Standard Planning Data:llis is the data a User whether connected directly or seeking such connection tothe Transmission Network shall provide the TSP of its Plant or Equipment at d1econnection site, which may have impact on the performance of the Nigerian

Electricity Network. In addition each Generator in Embedded Power stationgreater d1an l.OMW connected to the Distribution Network shall provide d1e TSPwith fault i..nfeed data as specified in dlis Code.User shall provide the TSP a Single Line Diagram, depicting bod1 its existing andproposed arrangement(s) of load current carrying equipment relating to bod1existing and proposed connection points that can impact on the Networkperformance.

4.1.4. D etailed Planning Data:l1ese are additional detail data where it may apply of d1e Users plant andequipment required by d1e TSP to conduct further studies if d1e Users plant and

equipment might have serious impact on d1e Transmission Network or e. ristingUsers already connected to the Network before allowing the User to connect to d1eNetwork. Tl1ese data must be provided widlin 30 business days after request.

4.1.5. Network Planning D ata:l1e data required in dlis category is in Append.L { 7.

4.1.6. Connection Planning Data:

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The Grid Code requires that at the time the TSP signs a Grid Connection andConstruction Agreements with the User, estimated values assumed in the StandardPlanning Data for planning purposes are confirmed or where practicable replacedby validated actual values. This data is then termed Connection Planning Data.Connected Planning Data is divided into:

(a) Forecast Data - items in d1e Standard Planning and D etailed PlanningData thatwill always be forecast data.(b) Registered Data - items in the Standard Planning and DetailedPlanning D ata which upon connection to d1e network become fi {ed

(subject to any subsequent changes)Connection Planning Data and other relevant Data held by the TSP when a newapplication is made shall form the background against which such application shallbe considered and against which planning for d1e entire network will be based. Withthe exception of other data, Users Registered Data shall be treated as nonconfidential.

4.2. ST ND RD PL NNING D T4.2.1. User s System Layout

Users connected or seeking connection to d1e Transmission Network shall provideSingle Line Diagram, depicting both its existing and proposed arrangement(s) ofload current carqing Equipment relating to bod1 existing and proposed ConnectionPoints. The Single Line diagram to be supplied is in addition to the Operationdiagram.The Single Line Diagram must include all parts of the User System operating atTransmission and sub Transmission Voltages at d1e Connection ite. Such diagrammust include all parts of d1e Users sub Transmission System operating at voltagesgreater d1an 20KV which under eid1er intact Network or Planned Outageconditions:

(a) normally interconnects separate Connection Points, or busbars at aConnection Point which normally mn in separate sections; or(b) connects Embedded Power Stations connected to the User s Sub-transmission System to a Connection Point.

The Single Line Diagram should also contain additional details of the UsersSubtransmission System not already included above and also details of the bulkpower transformers connecting the Users Subtransmission System to a lowervoltage, plus points at which demand D ata and fault infeed data are supplied.

4.2.2. The Single Line diagram shall include:Electrical circuitry i.e. overhead lines, identifying which circuits are on the sametowers, underground cables, power transformers, reactive compensation equipmentand similar equipment; and

(a) Substation names (in full or abbreviated form) wid1 Operating Voltages.(b) Circuit breakers



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(c) Phasing arrangements.For each circuit shown on the Single Line Diagram, each User shall provide thefollowing details relating to that part of its Users System:Circuit Parameters: Rated voltage KV) Operating voltage KV) Positive phase sequence reactance Positive phase sequence resistance Positive phase sequence susceptance Zero phase sequence reactance (both self and mutual) Zero phase sequence resistance (both self and mutual) Zero phase sequence susceptance (bod1 self and mutual)For each transformer shown in d1e Single line diagram, User shall provide thefollowing: RatedMVA Voltage Ratio Winding arrangement Positive sequence reactance (max, min, nominal tap) Positive sequence resistance (max, min, nominal tap) Zero sequence reactanceIn addition for all interconnecting bulk transformers between d1e UsersTransmission Voltage System and the User s Subtransmission System, d1e User shallsupply d1e following Tap changer range Tap changer step size Tap changer type: on load or off circuit Earthing med10d: direct, resistance or reactance Impedance (if not direcdy earthed)



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User shall supply the following about tl1e User s equipment installed at aTransmission Site: Switchgear: For all circuit breakers:-

o Rated voltage KV)o Operating voltage KV)o Rated 3-phase rms short-circuit breaking current kA)o Rated 1-phase rms short-circuit breaking current kA)o Rated 3-phase peak short-circuit making current kA)o Rated 1-phase peak short-circuit making current kA)o Rated rms continuous current (A)o D C time constant applied at testing of asymmetrical breaking abilities

(rms) Substation Infrastructure

(Tilis includes but not limited to switch dis-connectors, dis-connectors, currenttransformers, line traps, busbars, duough bushings etc)

o Rated 3-phase rms short-circuit withstand current kA)o Rated 1-phase rms short-circuit withstand current kA)o Rated 3-phase peak short-circuit withstand current kA)o Rated 1-phase peak short-circuit withstand current kA)o Rated rms continuous current (A)

Lumped System SusceptanceFor all parts of tl1e Users Subtransmission System wllich are not included in tl1eSingle Line Diagram, each User shall provide the equivalent lumped shuntsusceptance at nominal Frequency. Tllis should include shunt reactorsconnected to cables which are not normally in or out of se rvice independent ofthe cable e they are regarded as part of tl1e cable), but not includingindependently switched reactive compensation equipment connected to tl1eUser s System, or any susceptance of the User s system inherent in tl1e D emand(Reactive Power) data specified under tllis Code.

Reactive Compensation EquipmentFor all independently switched reactive compensation equipment including thatshown in the Single Line Diagram, not operated by TCN and connected to tl1eUser s System at KV and above, tl1e following information is required:



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o Type of equipment (fi {ed or variable)o Capacitive and/ or inductive rating or its operating range in MV ro Details of any automatic cont rol logic to enable operating characteristics

to be determinedo The point of connection to the User s System in terms of electrical

location and network voltage.4.2.3. Short Circuit Contribution to the TSP Transmission Network

(a) GeneralTo allow the TSP and System Operator to calculate fault currents, each User sis required to provide data, calculated in accordance with best internationalpractice as set out in this Code.T he data should be provided from d1e Users System wi th all Generating UnitsSynchronised to that User s System. The User must ensure d1at d1e pre-faultnetwork conditions reflect a credible System operating arrangement.The list of data items required, in whole or part under d1e following provisionsis set out in 4.2.4. The fault currents in sub-paragraphs (a) and (b) of the datalist in 4.2.4 should be based on a.c. load flow that takes into account any prefault current flow across d1e point of connection being considered.Where prospective short-circuit currents on equipment owned, operated ormanaged by d1e TSP are close to the equipment rating, and in TSP or SystemOperator reasonable opinion more accurate calculations of d1e prospectiveshort circuit currents are required, then the TSP may request additional shortcircuit data.(b) Data from Direcdy Connected CustomersDirecdy Connected Customers at each node on the Single Line Diagramprovided to the TSP shall provide motor loads and/ or E mbedded Small PowerStations and other installations of direct current converters which do not forma D C converter Station assuming a fault at that location, as follows:-

The data items listed under the following parts of 4.2.4(a) i), ), ii i), (iv), (v) and (vi)

nd the data items shall be provided in accordance to detailed provisions of4.2.4 (c) - .(c) Data from Users Generating Unit in a Power StationFor Users each Generating Unit in a power Station, wid1 one or moreassociated Unit Transformer(s), d1e User is required to provide values for d1econtribution of the Power Station AtL'Ciliaries (Including Auxiliary Gas Turbineor uxiliaq Diesel Engines) to d1e fault current flowing through d1e UnitTransformer(s). The data items listed under the following parts of subsection4.2.4 (a) should be provided:-



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( ), ) and (v)ill) if the associated Generating Unit step-up transformer can supply zerophase sequence current from the Generating Unit side to d1e Transmission

Network(lv) if the value is not 1.0 p.u.

The data item shall be provided ll accordance with the prov1s10ns ofsubsection 4.2.4 (c) - .Au,Wiary motor short circuit contribution and any Auxiliary Gas Turbine Unitcontribution through d1e Unit T ransformers must be represented as acombined short circuit current contribution at the Generating Unit s terminals,assuming a fault at that location.f d1e User s Power Station has separate Station Transformers, data should be

provided for the fault current contribution from each transformer at its highvoltage terminals, assuming a fault at d1at location as follows:-The data items listed under the following parts of 4.2.4

(a) (i) to (vi)And the data items shall be provided ll accordance wid1 d1e detailedprovisions of 4.2.4 (b)-(t)

Data for the fault infeeds duough bod1 Unit and Station Transformers shall beprovided for d1e normal running arrangement when d1e maximum number ofGenerating Units are Syncluonised to the Network. Where there is analternative running arrangement which can give higher fault infeed through d1eStation Transformers, then a separate data submission representing dllscondition shall be made.No account should be taken of d1e interconnection between the Station andUnit Board, unless d1e normal operating arrangement widlin the Power Stationis to have d1e Station and Unit Boards interconnected within the PowerStations.Au,-TIIlary motor short circuit current contribution through the StationTransformers must be represented as a combined short circuit contributionduough d1e Station Transformers.

4.2.4. D ata Items(a) Below is d1e list of data utilised in dlls part of the Planning Code. It

also contains rules on d1e data which generally apply:-(i) Root mean square of the symmetrical three-phase short circuit currentinfeed at d1e instant of fault Il ,).

) Root mean square of d1e symmetrical duee-phase short circuit currentafter the subtransient fault current contribution has substantiallydecayed (Il ) .



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(iii) T11e zero sequence source resistance and reactance values of tl1e User'sEquipment as seen from node on dle Single Line diagram providedunder 4.2.1 (or Station Transformer high voltage terminals orGenerating Unit terminals as appropriate) consistent witl1 dle infeeddescribe in 4.2.1

(iv) Root mean square of dle pre-fault voltage at which dle ma.'llinum faultcurrents were calculated;(v) T11e positive sequence X/ R ratio at tl1e instant of fault(vi) T11e negative sequence resistance and reactance values of dle User'sGenerating unit seen from node on dle Single Line diagram provided

under 4.2.1 (or Station Transformer high voltage terminals, orGenerating Unit terminals if appropriate) if substantially different fromdle values of positive sequence resistance and reactance which would bederived from tl1e data provided above.

(b) In considering tllis data, unless tl1e User notifies TCN accordingly atdle time of data submission, TCN will assume dlat dle time constant ofdecay of dle subtransient fault current corresponding to tl1e change from11 to 11 ' (f is not significantly different from 40ms. T11e User mustinform TCN if dle assumption is not correct in relation to an item of data.

(c) T11e value for X/ R ratio must reflect tl1e rate of decay of tl1e d.c.component tl1at may be present in the fault current and hence tl1at of tl1esources of the initial fault current. All shunt elements and loads mustdlerefore be deleted from any system model before tl1e X/ R ratio iscalculated.

(d) In producing tl1e data, dle User may use time step analysis or fL'\:ed-point-in-time analysis with different impedances.

(e) If a tL'\:ed-in-time analysis witl1 different impedances method is used,dlen in relation to dle data submitted under (a) (i) above, dle data will berequired for time zero to give 11 . The figure of 120ms is consistent witl1a decay time constant T ' of 40ms, and i tl1at figure is different, then tl1efigure of 120ms must be changed accordingly.

(f ~ h e r e a time step analysis is carried out, the X/ R ratio may becalculated directly from dle rate of the d.c. component. T11e X/ R ratio isnot dlat given by tl1e phase angle of dle fault current if tllis is based on asystem calculation widl shunt loads, but from tl1e T11everlin equivalent ofdle System impedance at tl1e instant of fault witl1 all non-source shuntsremoved.

4.3. GENER TING UNIT D T4.3.1. Directly Connected Generating Unit

Each Generator owner witl1 an existing, or proposed Power Station directlyconnected, or to be directly connected, to tl1e Nigerian Transmission System, shallprovide dle TSP widl data relating to dlat Power Station botl1 current and forecastas specified in 4.3.2 to 4.3.3.



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On receipt of this data, the Generator owner may be further required by the TSP orSystem Operator to provide details of Embedded Power Station data.\Xlhere Generating Units which term includes GT Units are connected to d1eTransmission Network via a busbar arrangement which is or is expected to beoperated n separate sections, the section of busbar to which each Generating Unitis connected is to be identified n d1e submission.

4.3.2. Output DataItems (a) to ) listed below shall be supplied by each User for its Generator, naccordance d1e type of generator involved: Large Power Stations and Generating Unit:

Data items n 4.3.2 (a) to (h) are required with respect to each Power Stationand each Generating Unit of each Large Power Station and for eachGeneratingunit.

Embedded Power StationsData item n 4.3.2 (a) is required wid1 respect to each Embedded Power Stationand Generating Unit.

GT Units/ ModulesData item 4.3.2 g) is required with respect to each GT unit.Data item 4.3.2 (a) is required with respect to each GT ModuleData item 4.3.2 b), (c), (d) and (e) are required with respect to each GTModule unless T N informs relevant User n advance of the submission d1at itneeds the data item with respect to each GT Unit. Where any definitionutilised or referred to n relation to any of d1e data items does not reflect

GT Units, such definition shall be deemed to relate to GT Units for d1epurpose of d1ese data items.

Hydro SchemesData item n Appendix 5 is required with respect to each Hydro Scheme.

(a) Data Items:Registered Capacity M\V)b) Output Usable M\Xl) on a mondlly basis

(c) Network Constrained Capacity (MW) which may be placed on d1ecapacity of an Embedded Generating Unit due to Network OperatorsSys tem n which it is embedded. Where d1e Embedded Generating Unitsconnected to a Distribution Network via a busbar arrangement which is oris expected to be operated n separate sections, details of d1e busbararrangements and connected circuits at the substation to which d1eEmbedded Generating Unit is connected must be provided to T N to



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determine where the power generated by the Embedded Generating Unitwould appear on the Transmission Network.(d) Minimum Generation \X(e) MW obtainable from User s Generating Units in excess of Registered

Capacity.(f Generator Performance Chart:i) at the Synchronous Generating Unit stator terminals) at the electrical points of connection to the Transmission Network (orUser System ifEmbedded) for a Non Synchronous Generating Unit

g) A list of GT Units wid1in a GT Module, identifying each GTUnit and the GT Module ofwhich it forms part, unambiguously in d1ecase of a Range GT Module, details of d1e possible configurationsshould also be submitted, toged1er wid1 details of d1e single GridConnection point at which power is provided from the Range GTModule including Embedded Range GT Module.

(Nodling shall prevent d1e busbar at the relevant point being operated inseparate sections)(h) Expected running regime(s) at each Power Station and type of

Generating Unit (e.g. Steam Unit, Gas Turbine Unit, Combined Cycle GasTurbine Unit, etc)i) A list of Power Stations and Generating Units widlin a cascade HydroScheme, identifying each Generating Unit and Power Station and d1ecascade Hydro Scheme of which each form part unambiguously. In

addition:i) details of d1e Transmission Network Entry Point at wl1ich Active Power

is provided, or if Embedded the Transmission Network Supply pointswithin which the Generating Unit is Connected.) where the Active Power output of a User Generating Unit is split

between more d1an one Transmission Network Supply Points d1epercentage that would appear under normal and Outage conditions ateach Transmission Network Supply point.

Without prejudice to paragraph g) above, identification of GT Units widlin aGT Module can only be amended in accordance wid1the following provision:

f the GT Module is a Normal or Range GT Module, d1e GTUnits wid lin that Module can only be amended if T N gives its priorconsent in writing. Notice of wish to amend d1e GT Units witl lin such

GT Module must be given at least 6 montl1s before it is wished for d1eamendment to take effect.4.3.3. Rated Parameter D ata

The following information is required to facilitate an early assessment of the needfor more detailed studies:(a) For all User s Generating Units - Rated MVA, Rated :tvi\ V



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b) For each Synchronous Generating Unit:i) Short circuit ratio) Direct . a s transient reactance

(ill) Inertia constant for whole machine), MWsecs/ MVA(c) For each Synchronous Generating Unit step-up transformer:

i) Rated MVA) Positive sequence reactance (at min and norminal tap)

4 4 DEM ND ND ACTIVE ENERGY D T

4.4.1. IntroductionEach User directly connected to tl1e Transmission Network with Demand shallprovide T Nwith Demand data - historic, current and forecast, as specified in tllisCode, apply equally to Active Energy requirements as to D emand unless tl1e contextotl1erwise requires.D ata will need to be supplied by

(a) Users, in relation to D emand and Active Energy requirements on tl1eUser s Systemb) Directly connected Customer in relation to its Demand and Active

Energy requirements4.4.2. Active Power and Energy Demand Data

Forecast daily Demand (Active Power) profiles as specified in (a), b) and (c) below,in respect of each of tl1e Users System (each summed over tl1e TransmissionNetwork Supply Points in each User System) are required for:Peak day on each of tl1e User s System giving tl1e numerical value of tl1e m ~ . a m u mD emand (Active Power) that in the Users opinion could reasonably be imposed onthe Transmission Network

(a) Day of peak demand on tl1e Transmission Network (Active Power) asnotified by System Operatorb) Day of minimum demand on the Transmission Network (Active

Power) as notified by System Operator(c) In addition, the total D emand (Active Power) in respect of the time ofpeak of tl1e Transmission Network D emand in tl1e preceding year for each

of the Users System summed over the Transmission Network Supplypoints, for outtu rn and weather corrected shall be supplied.4.4.3. By calendar week 20 T Nshall inform Users of tl1e Transmission Network inwriting of the following, for the current year and each subsequent 5 years, which w lluntil replaced by tl1e following year s notification:

(a) T11e date and time of tl1e annual peak demand of tl1e TransmissionNetwork D emand



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b) T11e date and time of tl1e annual minimum demand of the TransmissionNetwork Demand(c) Total Active D emand used on each of T N or Directly ConnectedCustomers (each summed over all grid Supply Points in each Userequipment) in the preceding financial year, together with a prediction of

the current financial, is enquired. Each Active Energy submission shall besubdivided into the following categories of Customer tariff:i) Low Voltage1) Low Voltage2

(iii) Low Voltage3(iv) High Voltage(v) Tractionvi) Lighting

In addition, tl1e total User losses and Active Energy provided by DistributedGenerators shall be supplied.4 5 DET ILED PL NNING D T

4.5.1. Introduction(a) Directly ConnectedEach User with existing Power Station(s) directly connected or to be directlyconnected to T Nnetwork shall provide T N witl1 data relating to the Plantand Equipment, both current and forecast as in 4.5.2 as applicable.b) Embedded

Users witl1 existing or proposed Embedded Power Station(s) shall provide TSPwitl1 data relating to the Embedded Power Station(s) botl1 current and forecast.(c) DemandFor each Users Generating Unit which has an associated Unit Transf01mer,tl1e value of tl1e Demand supplied tlnough this Unit Transformer when tl1eGenerating Unit is at Rated MW output is to be provided.Where tl1e Power Station has associated D emand additional to tl1e miltsupplied Demand which is supplied from either the Transmission Network ortl1e Generators Users equipment tl1e Generator User shall supply forecasts foreach Power Station of:T11e maximum Demand tl1at in tl1e Users opllllon could reasonably beimportant on T N network or the Generators User equipment as appropriate;

i) T11e Demand at the time of peak T N Network D emand;) T11e Demand at the time of minimum T NNetwork Demand



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By calendar week 20 T Nshall inform Users of d1e Transmission Network inwriting of d1e following, for dle current year and each subsequent 5 years,which will until replaced by d1e following year's notification:

) The date and time of dle annual peak of dle Transmission NetworkDemand(iv) The date and time of dle annual minimum of d1e TransmissionNetwork Demand

4.5.2. Synchronous Generating Unit and Associated control System DataThe following Synchronous Generating Unit and Power Station data should besupplied

(a) Synchronous Generating Unit Parametersi) Rated terminal volts kV)) Rated MVA) Rated MW

(iv) Minimum Generation MW(v) Short circuit ratio(vi) Direct synchronous reactance(vii) Direct transient reactance( ) Direct sub-transient reactance(L {) Direct axis short-circuit transient time constant(x) Quadrature synchronous reactance(xi) Quadracture ~ a s sub-transient reactance(xii) Quadracture axis short-circuit sub-transient time constantxiii) Stator time constant

(xiv) Stator leakage reactance(xv) Amature winding direct-current resistance(xvi) Turbogenerator inertia constant (MWsec/ MVA)(xvii) Rated field current (amps) at Rated MW and MVAr output and at rated

terminal voltage(xviii) Field current (amps) open circuit saturation curve for Generating Unit

terminal voltages ranging from 50 to 120 of rated value in 10steps as derived from appropriate manufactures test certificates.b) Parameters for Generating Unit Step-up Transformer(s)i) Rated MVA) Voltage ratio) Positive sequence reactance (at max, min nominal tap)

(iv) Positive sequence resistance (at ~ { , min nominal tap)(v) Zero phase sequence reactance



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(vi) Tap changer rangevii) Tap changer step size

) Tap changer type-on load or off load(c) Excitation Control System parameters(i) Excitation equipment Nominal Response(ii) Rated Field Voltage(iii) No-Load Field Voltage(iv) Excitation Equipment On-Load Positive Ceiling Voltage(v) Excitation Equipment No-Load Positive Ceiling Voltage(vi) Excitation Equipment No-Load Negative Ceiling Voltagevii) Details of Excitation Equipment describing in block diagram formshowing transfer of individual elements

) Details of Over-excitation Limiter describe in block diagram formshowing transfer functions of individual elements(L {) Details of Under-excitation Limiter describe in block diagram form

showing transfer functions of individual elements(d) Governor Parameters(i) Incremental Droop values (in )are required for each Generating Unit

as SL'{ MW loading points (NII..Pl to iLP6).(ii) Governor and associated prime mover Parameters - All GeneratingUnits

o Governor Block diagram showing transfer function of individualelements including acceleration sensitive elements

o Governor time Constant (in seconds)o Speeder Motor Setting range ( )o Average g in (MW Hz)o Governor Deadband - Maximum Setting ( Hz), Normal Setting(Hz), Minimum Setting ( Hz)

(where the Generating unit governor does not have a selectabledeadband facility, then d1e actual value of the deadband need only beprovided)

(iii) Governor and associated prime mover Parameters (Steam Units) :o HP Valve Time Constant (in seconds)o HP Valve Opening Limits ( )o HP Valve Opening Rate Limits ( / second)o HP Valve Closing Rate limits ( /second)



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o HP Turbine time Constant (in seconds)o IP Valve Time Constant (in seconds)o IP Valve OpeningLimits ( )o IP Valve Opening Rate Limits ( / second)o IP Valve Closing Rate limits ( /second)o IP Turbine time Constant (in seconds)o LP Valve Time Constant (in seconds)o LP Valve Opening Limits ( )o LP Valve Opening Rate Limits ( / second)

o LP Valve Closing Rate limits ( /second)o LP Turbine time Constant (ln seconds)

(iv) Governor and associated prime mover Parameters (Gas Turbine Units):o Inlet Guide Vane time Constant (in seconds)o Inlet Guide Vane Opening limits ( )o Inlet Guide Vane Opening rate limits ( /second)o Inlet Guide Vane Closing Rate Limits.( / second)o Fuel Valve constant (in seconds)o Fuel Valve Opening Limits ( )o Fuel Valve Opening Rates Limits ( /second)o Fuel valve Closing rate Limits ( /second)

(v) Governor and associated prime mover Parameters - Hydro GeneratingUnitso Guide Vane Actuator time Constant (is seconds)o Guide vane Opening limits ( )o Guide vane opening rate limits ( /second)o Guide Vane Closing rate Limits ( /second)o Water Time Constant (ln seconds)

(vi) Unit Control Optionso Maximum Droop



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0 Normal Droop0 Minimum Droop0 Maximum Frequency deadband Hz0 Normal Frequency deadband Hz0 Minimum Frequency deadband Hz0 Maximum outpu t deadband M\V0 Normal output deadband MW0 Minimum output deadband MW

(vii) Frequency settings between which Unit load Controller Droop applies:o Maximum Hzo Normal Hzo Minimal Hz

(viii) Plant Flexibility Performanceo Run-up rate to registered capacityo Run-down rate from registered capacityo Synchronising Generationo Regulating rangeo Load rejection capability willie still Synchronised and able to supplyLoad.

(L {) Response data for Frequency changesPrior to d1e Generator being first Synchronised, d1e MW LoadingPoints must take the following values:

0 :MLP1 Designed Minimum Operating Level0 :MLP2 Minimum Generation0 :MLP3 70 ofRegistered Capacity0 :MLP4 80 ofRegistered Capacity0 :MLPS 95 ofRegistered Capacity0 :MLP6 Registered Capacity

(x) Primaq and Secondary Response to Frequency Fall

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Primru.y and Seconda1y Response values for a -O.SHz ramp are requiredat six :MW Loading Points (MLPl to :MLP6) as detailed above.

xi High Frequency Response to Frequency RiseHigh Frequency Response valves for a +O .SHz ramp are required at six:MW loading points (MLPl to :MLP2)

4.6. TRANSIENT OVER VOLTAGE ASSESSMENT DATA

4.6.1. Each User is required to provide the following data with respect to theConnection Site current and forecast, together with a Single Line Diagram if not alreadyprovided.

(a) Busbar layout plan(s), including dimension and geometry showingposition of any current and voltage transformers, bushings, supportinsulators, disconnect switches, circuit breakers, surge arrestors etc.Electrical parameters of any associated current and voltage transformer,stray capacitance, of wall bushings and support insulators, and givingcapacitances of circuit breakers,

(b) Electrical parameters and physical construction details of lines andcables connected at the busbar. Electrical parameters of all plant (e.g.transformer- including neutral eartlling impedance or zigzag transformer ifany), series reactors and shut compensation equipment connected at tl1atbusbar (or to tl1e tertia1y of a transformer) or by lines or cables to thebus bar;

(c) Basic insulation levels of all Equipment connected directly by lines orby cables to the busbar,

(d) Fault levels at the lower voltage terminals of each trru.1sformerconnected directly or indirectly to the TSP Network without intermediatetransformation.

(e) ll transformers operating at 132KV ru 1d over, three or five limb coresor single phase units to be specified, ru.1d operating peak filL < density atnominal voltage.

4.7. USER S PROTECTION DATA

4.7.1. ProtectionThe following information is required which relates only to Protection equipmentwhich can trip or inter-trip or close any Connection point circuit breaker or anyT Ncircuit breaker. This information need to be supplied once ru 1d regular updatemade afterwards.

(a) Full description, including estimated settings, for all relays ru.1dProtection systems installed or to be installed on tl1e User s System;(b) Full description of auto-reclose facilities installed or to be installed onthe Users System, including type ru.1d time delays;

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(c) Full description, including estimated settings, for all relays andProtection systems or to be installed on d1e Generator, Generatortransformer, Station transformer and dleir associated connect ions

(d) Generating Units having (or intended to have) a circuit breaker at d1eGenerator terminal voltage, clearance times for electrical faults widlin d1eGenerating Unit zone

(e) Most probable fault clearance time for electrical faults on any part ofdle Users System direcdy connected to TCN Network.

4.7.2. Harmonic StudiesIn d1e course of operating dle Transmission Network, dle System Operator or d1eTSP will have to evaluate dle occurrence of harmonic distortion on dle Network orUser s Systems, especially when equipment like capacitor banks is involved. Forproper evaluation, n respect of dle Connection Site Users are required, to submitas follows data current and forecast data if not already submitted under 4.2.2 for anysub-Transmission System for overhead and underground cable circuits: Positive phase sequence resistance Positive phase sequence reactance Positive phase sequence susceptanceFor transformers connecting dle User s Subtransmission System to a lower voltage: RatedMV Voltage Ratio Positive phase sequence resistance Positive phase sequence reactance

nd at d1e lower voltage points of d1ose connecting transformers: Equivalent positive phase sequence susceptance Connection voltage and iV r rating of any capacitor bank and componentparameters if designed as a filter Equivalent positive phase sequence interconnection impedance wid1 od1er lowervoltage points The minimum and maximum Demand (bodl:MW and MV r) d1at could occur Harmonic current injection sources in Amps at d1e Connection voltage point s Details of traction load (e.g connection phase pairs, continous variation widl

time etc. )



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An indication of which items of equipment may be out of se1viCesimultaneously during planned Outage condit ion

4.7.3. Voltage Assessment Studies

In the course of operating d1e Transmission Network, System Operator will have toundertake voltage assessment studies on the Network to examine potential voltageinstability, Voltage Control co-ordination or calculate voltage step changes. Usersare required, to submit as follows data current and forecast data if not alreadysubmitted under 4.2.2 for any subtransmission System for overhead andunderground cable circuits:

(a) For Users Subtransmission System Positive phase sequence resistance Positive phase sequence reactance Positive phase sequence susceptance MVAr rating of any reactive compensation Equipmentb) For bulk transformers connecting d1e Users Subtransmission System to

a lower voltage: Rated 1viVA Voltage Ratio Positive phase sequence resistance Positive phase sequence reactance Tap-changer range Number of tap steps Tap-changer type: on-load or off-circuit AVC/ tap-changer time delay to first tap movement AVC/ tap-changer inte r-tap time delay(c) And at d1e lower voltage points of those connecting transformers

Equivalent positive phase sequence susceptance MVAr rating of any reactive compensation equipment Equivalent positive phase sequence interconnection impedance with od1er

lower voltage points Maximum demand (both MW, MVAr) that could occur.

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4.8. NETWORKD T4.8.1. If a User wants to model d1e TSP Transmission Network, d1e TSP shall providethe Network data indicated in 4.8.2 to allow the User properly calculate conditions onthe Network.4.8.2. Single and Multiple Point Connection

The TSP, or System Operator as correspond, shall provide User with followingdata:(a) Symmetrical duee phase short circuit current infeed at the instant offault from d1e TSP System (I1 )b) Symmetrical duee phase short circuit current from d1e T N System

after d1e subtransient fault current contribution has substantiallydecayed(I1 )(c) Zero sequence source resistance and reactance values at d1e Point of

Connection, consistent with d1e maximum infeed below(d) Pre-fault voltage magnitude at which the maximum fault currents werecalculated.(e) Positive sequence X/ R ratio at d1e instant of fault(f Negative sequence resistance and reactance values of d1e TSPTransmission System seen from d1e Point of Connectiong) Initial positive sequence resistance and reactance values of d1e two ormore sources and d1e linking impedances derived from a fault studyconstituting the p) equivalent and evaluated wid10ut the User network and

load(h) Corresponding zero sequence impedance values of the p) equivalentThe positive sequence X/ R ratio and zero sequence impedance will correspondto the TSP Network only.



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PART 3: CONNECTION CONDITIONS

1 SECTION PURPOSE AND SCOPE

1 1 OBJECTIVE

1 1 1 Tills Section (Connection Conditions) specifies the minimum technical, designand certain operational criteria which must be complied with by d1e Users connected to,or seeking connection to the Transmission Network. T11ey also set out d1e proceduresby which the Transmission Service Provider (TSP) will process an application toconnection to the Transmission System, seeking to ensure compliance with d1ese criteriaas a requirement for d1e granting of approval for d1e connection of a User to d1eTransmission System.1.1.2. The provisions of the Connection Conditions shall apply to all connections tothe T ransmission Network:

(a) existing at d1e date when this Grid Code comes into effect;b) existing at the date of commencement of d1e TSPs approval, wherethese dates precede the date in (a) above; and

(c) as established or modified d1ereafter.1.1.3. The Connection Conditions are designed to ensure that:

(a) o new or modified connection will impose unacceptable effects uponthe Transmission System or on any User network nor will it be subjectitself to unacceptable effects by its connection to the Transmission System.

b) T11e basic mles for connection treat all Users, within an equivalentcategory, in a non-discriminatory fashion.1 2 PURPOSE

1.2.1. The purpose of dus Connection Conditions is:(a) to specify d1e technical, design, and operational criteria at eachConnection Point;b) to ensure that there is no undue discrimination in the application of theGrid Code between Users or classes of User;

(c) to facilitate the use of the Transmission System by any User connectedto or seeking connection to the Transmission System, in accordance wid1 aConnection Agreement;



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d) to define the requirements for a User seeking connection and/ or for amodification of the current connection;e) to enable the TSP to develop, maintain and operate d1e Transmission

System n a coordinated and economic manner n compliance with itslicence;1.3. OP

1.3.1. The Connection Conditions apply to the System Operator, TSP and to Users ofthe Transmission System which n this Connection Conditions are:

a) Power Stations;b) Distributors;c) nterconnected Parties;d) Customers connected to d1e Transmission System.



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2. SECTION: T RANSMISSION SYSTEM PE RFORMANCECHARACTERISTICS

2.1. FRE QUENCY AND VOLTAGE2.1.1. In order to maintain the security and integrity of the Transmission System it isnecessaq d1at the System Operator operate the T ransmission System and Dispatch it insuch a manner in order to provide adequate Frequency Control so as to achieveoperation widlin applicable Frequency limits at all times.2.1.2. The nominal Frequency of the system will be 50 Hz. The National ControlCentre will endeavour to control the System Frequency within a narrow operating bandof 0.5 from 50 Hz, but under System Stress the Frequency on d1e Power Systemcould experience variations widlin d1e limits of 50 Hz 2.5 (48.75 - 51.25 Hz).2.1.3. All equipment and apparatus cormected direcdy or indirectly to the NationalGrid must operate at 50Hz frequency mode.2.1.4. Under extreme system fault conditions all Generating Units should disconnectby following frequencies unless agreed od1erwise in writing \vid1 the System Operator.

(a) By a frequency greater than or equal to [51.75] Hz.(b) By a frequency less d1an or equal to [48.5] Hz.

2.1.5. The System Operator shall endeavour to control d1e different busbar voltages tobe widlin the Voltage Control ranges specified in Table1:

Voltage level Minimum Voltage Maximum VoltagekV (pu) kV (pu)

330 kV 313.5 (0.95) 346.5 (1.05)132kV 118.8 (0.9) 145.0 (1.098)33kV 31 (0.94) 34.98 (1.06)16kV 15.2 (0.95) 16.8 (1.05)11 kV 10.45 (0.95) 11 .55 (1.05)

Table 1: Voltage Control rangesUnder System Stress or following system faults, voltages can be expected to deviate outsidethe above limits by a fmther 5 (excluding transient and sub-



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2.1.6. transient disturbances)2.1.7. Due to the effect of travelling waves on the Transmission Network as a result ofatmospheric disturbances or the switching of long transmission lines, transient over-voltagecan occur at certain node points of the network concemed. TI1e insulation level of allApparatus must be coordinated to take account of transient over-voltages and sensitive Userequipment, such as computer and other solid state equipment, should be suitably isolatedfrom this effect.2.1.8. TI1e transient over-voltage during lightning strikes is typically experienced over avoltage range of 20% of nominal voltage. Connection Points close to a network lightningstrike will experience voltages higher than this.2.1.9. Unless otherwise agreed by the TSP, the Basic Insulation Value BIV) for UserApparatus shall be as follows:

(a) For the 330 kV system, the BIV is 1300 kV.b) For the 132 kV system, the BIV is 650 kV.

2.2. VOLT GE PERTURB TIONS2.2.1. ''Voltage Flicker is a rapid change in voltage that is typically caused by Userequipment that distorts or interferes with the normal sinusoidal voltage waveform of d1eTransmission System. Such interference is a product of a relatively large current inrush whenApparatus, such as a large motor, is suddenly switched on, or resulting from the suddenincreased demand from for example welding equipment. Such distortions can disturb Usersequipment and cause, for instance through flickering lights, consumer annoyance. TI1e currentiruush acting over the network impedance is the mechanism that produces the voltage dip(sudden fall) and the corresponding voltage swell (sudden rise) when the Apparatus concemedis offloaded. Hence, the cause of the ' 'Voltage Flicker .2.2.2. Users are required to minimise d1e occurrence of Voltage Flicker on the TransmissionSystem as measured at the User's Connection Point. TI1e Flicker Severity at the ConnectionPoint of any User, shall not be above d1e ma.-IDnum values stated in IEC 61000-3 Standard formore than 3 % of d1e period. The ma.-IDnum emission limits produced by any User shall bebelow the maximum values stated in IEC 61000-3 Standard,2.2.3. n cases where, in the reasonable opinion of the System Operator, vanatlons ingeneration or demand constitute a risk to Transmission System operation, strict conformitywid1 d1e IEC 61000-3-7 flicker curve will be required.2.2.4. Harmonics are normally produced by User's Apparatus generating waveforms thatdistort d1e fundamental 50 Hz wave. Such harmonic generation can damage User Apparatusand can result in failure of Transmission System Apparatus. TI1e limits for harmonic distortionlevels are given in the following documents:

(a) EN 50160:2000 ''Voltage characteristics of electricity supplied by publicdistribution systems .b) IEC/ TR3 61000-3-6 (1996) Assessment of emission limits for distorting

loads in 1viV and HV power systems .

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2.2.5. n general, the ma.--cimum total levels of harmonic distortion on d1e System underNormal Operation conditions, planned outages and fault outage conditions (unless duringSystem Stress) shall not exceed following values:

(a) 330 kV a Total Harmonic Distortion of 1.5 with no individual harmonicgreater than 1

b) 132 kV a T otal Harmonic Distortion of 2 with no individual harmonicgreater of 1.5.2.2.6. Under Normal Operation, the ma...Umum negative phase sequence component of d1ephase voltage of the Transmission System should remain below 1.2.2.7. Under planned outage conditions, infrequent short duration peaks with a maximumvalue of 2 are permitted for phase unbalance.

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3 SECTION CONNECTION PROCESS

31 APPLICATION FOR CONNECTION

3.1.1. Application. Users proposing a connection to the Transmission System, either througha new substation, a modification of an existing substation, or in an existing substation shallsend an application to the TSP. f llis demand for new connection falls outside tl1e approvedRegulatory Long Term Transmission Plan, the cost for such works shall be borne by tl1e User.3.1.2. Application information: User(s) shall submit tl1e application on an application formwhen making an application for a connection to the Transmission System. Amongst otl1erinformation, the application form shall include:

(a) A description of tl1e Plant or Apparatus to be connected to the TransmissionSystem or, the modification relating to the Participant s Plant or Apparatusalready connected to the Transmission System

b) Confirmation that the Users Plant and Apparatus at the Connection Pointwill meet tl1e required technical standards in tl1is Grid Code, and safetyregulation as agreed witl1 tl1e TSP where appropriate.(c) The technical data (as stipulated in Appendices 5, 6, 7 anticipated for tl1eUsers modified or new Plant or Apparatus, specifying the Load characteristics

and other data. The TSP shall compile a standard list of detail required from tl1eParticipant; and

nerc nigeria gridcode v0l1

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