Using so-called green hydrogen to heat homes and other buildings would require so much electricity to simply manufacture the gas that it would consume all the wind power Massachusetts expects to be generating by the end of the decade, a new report concludes.
The report’s authors said that would derail the state’s plans to rely on clean electricity as the main fuel driving a carbon-free economy and should cast doubt on any proposal to lean on green hydrogen as a fuel for home heat.
Hydrogen does not produce greenhouse gas emissions when burned, making it an attractive fuel of the future. But traditional manufacturing has commonly required large amounts of natural gas. Green hydrogen, on the other hand, is produced without fossil fuel, relying instead on water and carbon-free electricity.
The process is so energy intensive, however, that it would “cannibalize the supply of clean electricity, diverting it from its primary targeted purpose” of greening the electricity grid, the authors wrote.
“That offshore wind power is central to the plans of Massachusetts to achieve its climate action plans, to build, in effect, a green grid,” said the report’s lead author, Martyn Roetter, a technology and management consultant with a doctorate in physics. “If we really are going to use green hydrogen to heat buildings, either progress to make the grid green will be drastically impaired and slowed, or it may, in fact, become impossible.
The report, prepared for Gas Transition Allies, a consortium of climate advocacy groups and scientists that argues for a rapid transition away from gas, comes as the state Department of Public Utilities deliberates the shape and form of a massive transition away from fossil fuels. A key question in the proceeding, called the “Future of Gas,” is how best to heat buildings, including homes. The state’s official plan calls largely for electric heat pumps powered by a clean grid, a course endorsed by climate advocates. But gas utilities are pushing plans that would swap the fuel running through gas pipes from methane to a mix of purportedly climate-friendly fuels, including green hydrogen, in addition to heat pumps.
The amounts of green hydrogen proposed by individual utilities vary. National Grid specified 20 percent green hydrogen in its mix of fuels by 2050.
Monday’s report concluded that 3.9 gigawatts would be needed to produce enough green hydrogen to make- up 20 percent of the gas consumed in the state—an amount of electricity that far exceeds the 3.2 gigawatts of wind power that the state is in the process of developing. The report did not include solar capacity or account for additional wind capacity that will come on line in coming decades.
Pradheep Kileti, director of National Grid’s future of heat strategy in the US, rejected the idea that the utility’s plans are at odds with the state’s goals. The company’s plan, he said, is intended to ensure that every customer who wants to get off of traditional fossil fuels is able to. “We want to make sure either they are on electric heat pumps, or they’re having access to renewable natural gas and hydrogen. That’s where we are at.”
But clean energy advocates disagree, noting that the state’s own climate plan calls for a majority of homes to use electric heat pumps for heating and cooling, which are far more efficient than gas. “As the report highlights, pathways that rely on using local renewable electricity to generate hydrogen for heating buildings are going to require more than three times as much renewable electricity,” said Ben Butterworth, director of climate, energy and equity analysis for the advocacy group Acadia Center.
Moreover, he said, the utilities’ plans also call for a large amount of renewable natural gas, also known as biomethane, which he said is “extremely limited in quantity, expensive and better used in hard-to-electrify sectors of the economy.”
Sarah Griffith, a volunteer with Gas Transition Allies, said the group pursued the report to give state officials access to information as they consider what direction to take the state. “Hydrogen will have a role in our carbon free future,” she said. “But given the health, safety, affordability, and emissions issues—and now the fact that we wouldn’t be able to achieve our goal of a clean grid—it makes no sense to heat homes with hydrogen.”
Eversource has been less bullish on using green hydrogen. In a statement, spokeswoman Caroline Pretyman said the utility has “not set any prescribed targets for hydrogen conversion nor have we proposed any specific project plans.” She said they are reviewing the report and said their approach to green hydrogen will be “tailored to evaluating hard-to-electrify uses, such as with our large C&I customers, to compliment electrification efforts.”
Robert Howarth, a professor of ecology and environmental biology at Cornell University and a member of the New York State Climate Action Council, said he found the report to be well-reasoned and thoroughly documented. “I completely agree with their conclusions,” he said via email.
The state’s Future of Gas proceeding began during the administration of Governor Charlie Baker at the request of then-Attorney General Maura Healey. The public utilities department came under fire for allowing gas utilities to take the lead in the process, including from Healey. As governor, she has the ability to replace two of the three DPU commissioners whose term limits are up, and it will be the current DPU that issues an order on the proceeding some time this year.