How the Maximum Contingency of two,200 MW Was Recast to a 1,200 MW Ceiling
As coverage makers and power builders look to develop and interconnect massive offshore wind tasks in essentially the most economically environment friendly and least environmentally impactful approach, a problem has developed. A comparatively latest restrict, set in place by the grid operator in New England in a planning course of doc, states that no single system lack of power, or “contingency”, might be bigger than 1,200 megawatts (MW). This 2016 addition to ISO New England’s (ISO-NE) Planning Procedure No. 5-6 is more and more creating consternation amongst each coverage makers and builders and threatening to boost the fee and impacts of offshore wind. Part of the reason being {that a} de facto commonplace has developed in Europe that makes use of 2,000 MW 525 kilovolt (kV) excessive voltage direct present (HVDC) cable programs to interconnect offshore wind, with tens of billions of {dollars} of those programs already ordered and scheduled to be in service by the tip of this decade. The 2,000 MW measurement permits for single wind tasks to be bigger and profit from economies of scale unfold over extra energy manufacturing per undertaking and vital reductions within the variety of HVDC transmission programs wanted to attach these tasks to the grid. To meet New England’s projected want of 30,000 MW of offshore wind energy, 10 extra HVDC cables and related converters at a number of a whole bunch of tens of millions of US {dollars} every could be required if the 1,200 MW single supply restrict continues to use.
At the identical time, the complicated and opaque historical past of the 1,200 MW restrict has led to the impression that this has been a long-standing ceiling within the area and a way that it will be a major effort to elevate the restrict. If the 1,200 MW ceiling is comparatively latest, what’s the long-standing single supply New England loss restrict agreed to by the predecessors of the New York Independent System Operator (NYISO), ISO-NE, and PJM Interconnection (PJM) in 1991? 2,200 MW. Instead of a ceiling, the 1,200 MW is a ground that the three programs will redispatch energy flows on their system to take care of.
The 1991 settlement, the “Procedure to Protect for the Loss of Phase II Imports,” set 2,200 MW as the only supply loss ceiling and established a course of for assessing situations within the NYISO and PJM programs via an examination of seven reactive situations. In PJM, this consists of energy flows throughout three specified strains, and in NYISO, there are 4 monitoring factors consisting of voltages at three substations and energy flows on the Central East Interface. Any restriction beneath the two,200 MW stage right down to 1,200 MW, and any level in between, is an at the least hourly calculation involving a control-to-control room verify. The 1,200 MW worth doesn’t seem within the 1991 settlement, however is noticed by the three grid operators because the decrease restrict underneath which system operators will redispatch technology to take care of. The 1991 settlement was filed with the Federal Energy Regulatory Commission (FERC) in Docket No. ER07-231-000 on an “informational” foundation in November of 2006 as a result of it didn’t comprise “rates, terms, or conditions” underneath the Federal Power Act (FPA). FERC rejected that informational characterization in its January 12, 2007 order, and accepted the submitting underneath Section 205 of the FPA. The 1991 settlement might be discovered on the FERC web site utilizing the quotation 111 FERC ¶ 61,017.
The introduction of the 1991 Procedure to Protect for the Loss of Phase II Imports
In sensible phrases, which means that, since 1991 till the current day, assets just like the Phase II HVDC line from Canada to the United States that may function at as much as 2,000 MW, the Boston-based Mystic Generating Station items 8 and 9, which collectively are a 1,600 MW single supply loss because of a standard pure fuel gas supply difficulty from an adjoining liquefied pure fuel gasification facility, and the area’s two remaining nuclear crops, Seabrook in New Hampshire and Millstone in Connecticut, can all function above 1,200 MW and as much as their limits so long as system technology dispatch and ensuing energy flows on the New York and PJM programs enable. The 2016 planning course of restrict solely applies prospectively to new assets – HVDC strains interconnecting offshore wind included.
As extra focus was positioned on the 1,200 MW restrict by coverage makers and builders, in March of 2023, ISO-NE despatched a letter to the Joint ISO/RTO Planning Committee requesting a coordinated research amongst ISO-NE, NYISO, and PJM to find out if the 1,200 MW restrict could possibly be raised. ISO-NE described the 1,200 MW design restrict as a method to handle the difficulty as one among “daily unpredictability” concerning the scale of the only contingency restrict underneath the 1991 settlement. In its letter, ISO-NE notes the scale of bigger assets could possibly be “constrained by an otherwise optimal interconnection design,” and asks the Joint ISO/RTO Planning Committee to evaluate the supply restrict to see if it may be elevated. ISO-NE famous the higher restrict for a single system contingency to be 2,000 MW — as an alternative of the acknowledged 2,200 MW — and sought research as much as that decrease 2,000 MW restrict. While a 2,000 MW working ceiling would accommodate the rising offshore wind transmission commonplace set in Europe, it’s value noting that that is nonetheless 200 MW beneath the utmost stage grid operators recognized in 1991 and is contained within the ISO-NE tariff, the one higher restrict in a doc that has been reviewed and accepted by ISO-NE’s regulator, FERC.
One attention-grabbing aspect of the ISO-NE request is that ISO-NE itself that has set the 1,200 MW ceiling as a design restrict, not PJM or NYISO. The ISO-NE may equally take away its self-imposed restrict and as an alternative abide by the hourly check-in set out within the 1991 settlement for brand spanking new assets as much as the two,200 MW ceiling.
Regardless of the end result of the train that ISO-NE has undertaken, coverage makers and builders may additionally try to work round ISO-NE’s 1,200 MW ceiling by guaranteeing that the lack of bigger cables doesn’t end in a simultaneous lack of greater than 1,200 MW throughout the ISO-NE footprint. Suggestions from trade have included networking amenities from inception in order that there are a number of paths for energy to movement. The creation of HVDC breakers and industrial deployment of that expertise in western European over the subsequent 5 years could make the networked answer possible, however the New England states must specify or agree upfront to networking in transmission requests for proposals and ISO-NE might want to verify that extra transmission paths would deal with the only supply loss difficulty.
Until one among these or one other answer to handle the lowered single contingency restrict is adopted, offshore wind tasks and transmission circuits in New England will seemingly proceed to see limits of 1,200 MW.
* As revealed within the November/December version of Marine Technology Reporter.
About the Authors
Theodore Paradise is a accomplice in Ok&L Gates’ Boston and New York workplaces the place he assists shoppers in navigating the altering panorama of the electrical trade, advising shoppers concerning ISOs and RTOs, offshore wind, and transmission improvement.
Washington, D.C., accomplice Kimberly Frank co-leads the agency’s world Power observe group and focuses her electrical regulatory observe on representing shoppers in issues earlier than FERC and state utility commissions.
Ruta Skučas is a federal power regulatory and wholesale electrical energy markets accomplice in Washington, D.C., and advises shoppers on electrical and pure fuel issues earlier than FERC, in addition to ISOs and RTOs.
