2009 Scenario Reliability Assessment - NERC

Scenario Reliability Self-AssessmentsISO-NE is not aware of any future unit retirements, and does not make projections aboutpotential retirements, although the potential for retirements may be considered part of systemdesign. This unit retirement assumption (of no assumptions) is the same within both theReference and Scenario Cases. As noted earlier, nuclear plant relicensing and once-throughcooling issues are probably the only major open issues at this time.The assumption on the deliverability of resources is the same within both the Reference Case andthe Scenario Case. ISO-NE currently addresses generation deliverability through a combinationof transmission reliability and resource adequacy analyses. Detailed transmission reliabilityanalyses of sub-areas of the New England bulk power system confirm that reliabilityrequirements can be met with the existing combination of transmission and generation. Multiareaprobabilistic analyses are conducted to verify that inter-sub-area constraints do notcompromise resource adequacy. The ongoing transmission-planning efforts associated with theNew England Regional System Plan (RSP) support compliance with the NERC TransmissionPlanning requirements and assure that the transmission system is planned to sufficiently integrategeneration with load.As a notable generic exception to the statement above, there currently exists several bulktransmission interfaces on the New England system, which are currently impacted by thermal,stability, and voltage limitations. These transmission interfaces limit the free flow of poweracross the system. Assuming the mandate of an accelerated integration of renewable resources asmandated by the Scenario #1 requirement, it would be a safe assumption for New England that amajority of these new renewable resource that would be expected to be commercialized andoperating during the target assessment year 2018, and thus would require a some build-out of theexiting transmission system within the Region to accommodate the influx of 4,654 MW of newrenewable capacity. Depending on where these projects are physically located and thus“electrically-located,” they may either be on the “right-side” or “wrong-side” of an existingtransmission interface, thus either helping to dampen the constraining effects of the transmissioninterface or exacerbating it. Thus, aside from the standard supply-side resource interconnectionprocess for which either a minimum transmission interconnection standard or a maximum 69(output) transmission interconnection standard could be applied, some amount of additionaltransmission expansion would definitely be required to ensure the unconstrained delivery of thisnew renewable power throughout the existing ISO-NE system.Under the Scenario Case, over 4,654 MW of new, renewable resources is assumedcommercialized for the target year 2018. Because over one-third of the exiting capacity withinNew England is fossil-fueled, natural gas-fired technologies (SC & CC), the integration of 4,654MW of renewable resources would work to diversify a power generation fleet that is alreadyover-reliant on gas-fired generation. Variable generation like wind has no fuel source, and theremaining renewables, biomass, landfill gas, small hydro-electric, and fuel cells 70 would usepower plant fuels that are considered renewable in nature, thus providing resource and fueldiversity to the Regional fleet.69 Currently referred to within the FCM as the Capacity Capability Interconnection Standard (CCIS).70 However, fuel cells would need to be fueled by pipeline quality natural gas, and as such, would be an incremental(although minimal) gas load upon existing pipelines and/or gas LDCs.2009 Scenario Reliability Assessment Page 91