A new study by The Brattle Group said New England can achieve its ambitious 2050 target of cutting its greenhouse gas emissions by at least 80% from 1990 levels, but only if the region boosts its deployment of new renewable energy resources by an additional 4 GW to 7 GW annually.
All of New England's six states are aiming to reduce their emissions by 80% by 2050 and have made various commitments to do so; Maine Gov. Janet Mills, a Democrat, most recently directed state officials to achieve a carbon-neutral economy by 2045. This is on top of legislation Mills signed in June mandating that 80% of Maine's electricity come from renewables by 2030 before reaching 100% by 2050.
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Brattle's economists determined that in addition to New England ramping up the deployment of solar, hydropower, and onshore and offshore wind resources across the region and its ISO New England power markets, expanding energy efficiency and the electrification of the building and transportation sectors are also needed to achieve the 80% greenhouse gas reduction targets.
The greater electrification of New England's economy could double regional electricity demand by 2050, even when accounting for substantial energy efficiency gains, according to the Brattle study, which was prepared on behalf of the Coalition for Community Solar Access.
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Brattle said that as a result, New England's power sector over the next three decades "faces dual challenges and opportunities: supplying twice as much electricity while replacing almost all of the coal- and gas-fired power plants with a new set of emissions-free resources."
Given that most renewable resources generate electricity during fewer hours a year than most coal- or gas-fired power plants, the study said capacity, including energy storage, will need to grow even more. For New England as a whole, this could mean the region will need up to 160 GW of renewable capacity by midcentury, the study said.
To meet this higher electricity demand with renewable energy, the rate of deployment for such resources across New England will need to increase fourfold to eightfold from the currently planned deployment rate, to 4 GW to 7 GW of additional new renewable capacity per year on average, from 2021 through 2050, Brattle found. To reach these installed capacity levels, annual renewable additions will need to continue to grow by about 9% annually through 2050.
Merely maintaining the current deployment rate of clean energy resources will cause New England to fall short of its targets, the study warned. Clean energy resource generation now planned for 2019 through 2030 in New England is about 830 MW annually. From 2010 through 2018, New England saw clean energy generation additions at a slower rate of about 280 MW annually.
Jürgen Weiss, a Brattle principal and the study's co-author, said in a news release that realizing that large-scale investments are needed to fund any accelerated clean energy deployments is essential. "Given that more and more states and communities are adopting [greenhouse gas] reduction goals, the findings about New England are broadly applicable to regions that are currently examining the mechanisms by which they can reduce their carbon footprints, even if the details differ," Weiss said.
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Choose your own 2050 generation portfolio mix
The study envisioned three electric generation portfolio mixes for 2050 to supply New England, with each scenario limiting natural gas-fired generation to 13 TWh, or 5% of demand.
Under the "Large-Scale Resources" portfolio mix, the study foresees a scenario of New England maintaining the Millstone and Seabrook nuclear power plants, procuring 4 GW of incremental hydropower imports from Canada, and relying on large-scale renewable procurements. In this mix, New England would have a total supply capacity of 145 GW, 13 GW of which would be solar energy storage capacity needed to meet peak demand. The scenario also envisions the need to curtail 23% of renewable generation due to periods of overgeneration and limited storage capacity.
In contrast, the study's "Balanced Portfolio" mix for 2050 would keep NextEra Energy Inc.'s 1,249-MW Seabrook nuclear plant in New Hampshire online but retire Dominion Energy Inc.'s 2,100-MW Millstone nuclear facility in Connecticut while adding 3 GW of incremental hydro imports and procuring a mix of wind and solar resources. At a larger 191-GW total supply capacity, this mix would also include 28 GW of energy storage capacity and increase renewable curtailments to 25%. Specifically, 107 GW of solar would account for about 50% of this capacity but supply 37% of New England's electricity. In contrast, 47 GW of wind capacity, primarily offshore, would provide nearly 50% of the region's power.
Connecticut regulators recently approved 10-year power supply contracts between Millstone and local utilities for half of the nuclear plant's output at above-market prices. The contracts are aimed at preventing the early retirement of the nuclear power plant and safeguarding its emissions-free baseload power by shoring up its economics in an electricity market awash with cheap natural gas supplies.
The third "Local Solar and Storage" scenario envisioned New England relying more heavily on local solar and storage resources while limiting large-scale procurements of nuclear and hydro imports. Under this mix, New England would have a total supply capacity of 237 GW and 48 GW of energy storage capacity, with projected renewable curtailments at 27%.
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Among its other findings, the study said both solar photovoltaic and offshore wind energy will likely play a critical role in decarbonizing New England's economy and meeting its increased electricity demand. However, the study acknowledged that each energy resource faces constraints that threaten to limit their roles, such as local opposition to the construction of renewable or hydro-supplied transmission lines.




