NOM METHODOLOGY AND EXAMPLES AVAILABLE CAPACITY CALCULATION Thisisamapof‘firmsubstationcapacity’(determinedbythelocalreliabilitycriteria),minustheforecastpeakdemandattheZoneSubstationlevel.Datamappedisfortherelevantcriticalpeakseason(summerorwinter)ateachZoneSubstation.Whereaconstraintoccursinbothseasons,theseasonwiththelargestcapacityshortfalloverthetimehorizonismapped.ThevaluesinayearYarecalculatedasfollows:

𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 𝑌 = 𝐹irm substation capacity − 𝐹𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑝𝑒𝑎𝑘 𝑑𝑒𝑚𝑎𝑛𝑑(𝑌)

Datamappedisfortherelevantcriticalpeakseason(summerorwinter)ateachZoneSubstation.Whereaconstraintoccursinbothseasons,theseasonwiththelargestcapacityshortfalloverthetimehorizonismapped.

Example#1ZS(Summerconstrainedzone)

𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 2020 = 𝐹irm substation capacity − 𝐹𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑝𝑒𝑎𝑘 𝑑𝑒𝑚𝑎𝑛𝑑 2020

= 66𝑀𝑉𝐴 − 70.3𝑀𝑉𝐴 = −4.3MVA

ANNUAL DEFERRAL VALUE CALCULATION Ifanon-networkinvestmentcaneffectivelydeferinvestmentinupgradinganetworkasset,thenthereisafinancialbenefittothenetworkassociatedwiththatdeferral.Theannualdeferralvalue(ADV)inyearYin$/kVAyris:

𝐴𝐷𝑉 𝑌 = 𝐴𝑃𝐷 𝑥 𝑊𝐴𝐶𝐶 + 𝐷𝐸𝑃𝑅 𝑆𝑅(𝑌)

Where:

Yistheyearforthecalculatedvalue

APDistheamountoftheinvestmentpotentiallydeferrable

WACCisWeightedAverageCostofCapital(nominalvanilla)

DEPRistheDepreciationRate(straightline,averageweighedlifespan30yrs)and

SRistheSupportrequiredspecifiedbytherelevantNSPinyearY

NotethatwhentheNSPdoesn’tprovidethesupportrequiredasadistinctfield,availablecapacity(firmsubstationcapacityminusforecastloadinthecriticalseason)isusedinstead.

Example#1ZS(Summerconstrainedzone)

𝐴𝑛𝑛𝑢𝑎𝑙 𝐷𝑒𝑓𝑒𝑟𝑟𝑎𝑙 𝑉𝑎𝑙𝑢𝑒 2022 = $20.16𝑚 𝑥 . 0668 + .033 14.4𝑀𝑉𝐴 = $139.2/𝑘𝑉𝐴𝑦𝑟

WhenDMattheZSlevelcanalsopotentiallydeferupstreaminvestmentsaneffectivenessfactor(EF)isusedtotransferthedeferralvaluefromtheupstreamnetworkassettothezonesubstationlevel.InthiscasethetotalADVofthezonesubstationiscalculatedas:

NOM METHODOLOGY AND EXAMPLES

𝐴𝐷𝑉 𝑌 = 𝐴𝑃𝐷 𝑥 𝑊𝐴𝐶𝐶 + 𝐷𝐸𝑃𝑅 𝑆𝑅(𝑌) + 𝐸𝐹!𝑥𝐴𝐷𝑉!!!!"#$%&'(

!""#$"

Where:

EFistheeffectivenessfactorforthespecificzonesubstationandupstreamasset

ADVTistheannualdeferralvalueoftheupstreamasset

Example#2ZS(Summerconstrainedzone)

ThisisonecasewhereDMattheExample#2ZScanpotentiallydeferbothaninvestmentatthezonesubstationlevelandanotherupstreamsubtransmissioninvestment.Thecalculationhereisasfollows:

𝐴𝐷𝑉 𝑠𝑢𝑏𝑡𝑟𝑎𝑛𝑠𝑚𝑖𝑠𝑠𝑖𝑜𝑛 2022 = $1.5𝑚 𝑥 . 0617 + .033 114.2 − 93 𝑀𝑉𝐴 = $6.7/𝑘𝑉𝐴𝑦𝑟

𝐴𝐷𝑉 2022 = $6.5𝑚 𝑥 . 0617 + .033 (96.5 − 74)𝑀𝑉𝐴 + 1 𝑥 $6.7/𝑘𝑉𝐴 = $27.3/𝑘𝑉𝐴 + $6.7/𝑘𝑉𝐴= $34/𝑘𝑉𝐴𝑦𝑟

PEAK DAY AVAILABLE CAPACITY

Thismaplayershowstheavailablecapacity(asa%ofassetcapacity)foreachhourofthepeakdayinthelowestlevelofthenetworkwithpotentiallydeferrableinvestment.Threevaluesareshowninthismaplayerfortheyearwhensupportisrequiredforfirsttime.AttimeTinthepeakdaytheyarecalculatedasfollows:

𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 𝑇 = 𝐹𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑝𝑒𝑎𝑘 𝑙𝑜𝑎𝑑(𝑇) − 𝐹irm substation capacity

𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 % 𝑇 = 100 𝑥 𝐹𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑝𝑒𝑎𝑘 𝑙𝑜𝑎𝑑(𝑇) − 𝐹irm substation capacity

𝐹irm substation capacity

𝐻𝑜𝑢𝑟𝑙𝑦 𝑒𝑥𝑐𝑒𝑒𝑑𝑎𝑛𝑐𝑒 𝑠ℎ𝑎𝑟𝑒 𝑎𝑠 % 𝑜𝑓 𝑎𝑛𝑛. 𝑡𝑜𝑡𝑎𝑙 𝑇 = 100 𝑥 𝐹𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑝𝑒𝑎𝑘 𝑙𝑜𝑎𝑑(𝑇) − 𝐹irm substation capacity

𝐴𝑙𝑙 𝑒𝑥𝑐𝑒𝑒𝑑𝑎𝑛𝑐𝑒!!!"# !"#!

Example#2ZS(Summerconstrainedzone)

Herethemappedyearis2019,thesummerforecastloadis95.7MVA,theassetcapacityis74MVA,theloadat2pminthepeakdayis87MVAandthereare63exceedancehourswhichhaveasummationof558.4MVA:

𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 2𝑝𝑚 = 87𝑀𝑉𝐴 − 74𝑀𝑉𝐴 = 13𝑀𝑉𝐴

𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 % 2𝑝𝑚 = 100 𝑥 87𝑀𝑉𝐴 − 74𝑀𝑉𝐴

74𝑀𝑉𝐴= 17.6%

𝐻𝑜𝑢𝑟𝑙𝑦 𝑒𝑥𝑐𝑒𝑒𝑑𝑎𝑛𝑐𝑒 𝑠ℎ𝑎𝑟𝑒 𝑎𝑠 % 𝑜𝑓 𝑎𝑛𝑛. 𝑡𝑜𝑡𝑎𝑙 2𝑝𝑚 = 100 𝑥 87𝑀𝑉𝐴 − 74𝑀𝑉𝐴

558.4𝑀𝑉𝐴= 2.3%