Hydrogen for heating is gaining steam. Is it safe?

By Christine Mui | 11/20/2023 06:46 AM EST

Dominion Energy Utah’s ThermH2 project raises a question about how to best incentivize emerging clean technologies.

Rendering of blue hydrogen tanks


A Utah project set to start up “green” hydrogen production this month is underscoring a national debate over how the fuel should be used, who should fund it and if it’s safe to heat homes.

By the end of November, Dominion Energy Utah, which blends methane-derived hydrogen in its natural gas pipelines, plans on switching to a green version made on-site with renewable electricity.

Almost 2,000 customers in the state now have stoves and furnaces partially fueled by hydrogen, making Dominion’s project one of the most advanced in the country in using the fuel for home heating.


But environmentalists and some developers have rejected heating homes with hydrogen, considering the availability of cheaper, low-carbon options like electric heat pumps. Critics also warn that pollutants released from burning hydrogen in indoor spaces could worsen health problems and that it can be dangerous to introduce the fuel into pipelines designed for gas.

“Right now, there’s a lot of discussion on: ‘Should heating be supported?’” said Marina Domingues, a senior hydrogen analyst at Rystad Energy. “Why should the heating sector be a hydrogen-demand sector if we could just use natural gas and capturing technologies?”

Heating projects like Dominion’s ThermH2, as it is known, exemplify an ongoing question facing emerging clean technologies: Is funneling money to a few applications the best way to incentivize them, or is it preferable to support a range of pilots to see what sticks?

David Blekhman, a California State University, Los Angeles, professor who researches hydrogen infrastructure, summed up his stance on that question in three words: “I support everything.” He compared the sector’s path forward to running a race: “We are just raising that leg on the start line.”

His view echoes that of Dominion Utah, the state’s largest gas supplier. “With any new technology, advancements happen, and they start out kind of expensive,” said Jorgan Hofeling, a company spokesperson. “Green hydrogen is in that realm.”

“If it does reach that point where it makes sense for customers — that it really is a sustainable option — we’ll have already done the work to be able to deploy it to them, rather than starting from square one,” she continued.

Hydrogen’s head-scratcher

Currently, green hydrogen is several times pricier than natural gas and other conventional fuels. Driving its cost down is a major goal of the Biden administration, which will provide as much as $100 billion in Inflation Reduction Act tax incentives for making hydrogen. Last month, the Department of Energy announced plans to award $7 billion from the infrastructure law to seven proposed hubs around the country that it hopes will produce a combined three million metric tons of hydrogen annually.

Few U.S. green hydrogen projects the pre-development phase, meaning that most decisions have yet to be made about which end uses of the fuel will dominate the market.

Energy Secretary Jennifer Granholm has said hydrogen “can do just about everything” from heating homes to powering buses, calling it a “Swiss Army knife” of zero-carbon solutions during a speech in Philadelphia in October.

“We’re not so bold there to think that we can dictate what the market will do over time — and some of this, we’ll find out where folks want to spend their money,” said Chris Green, chair of the DOE-funded Pacific Northwest Hydrogen Hub, at an Oct. 30 community briefing on its projects.

Top of mind for many developers is avoiding applications where hydrogen is unlikely to succeed because it’s too expensive, unsafe or inefficient.

“A more deliberate approach to make the correct amount of hydrogen that is needed for decarbonization goals is the proper way to go,” said Green, whose hub will not support home heating.

Environmentalists and analysts are also urging the industry to exercise more caution when choosing projects to pursue. The World Resources Institute, for instance, advises governments to prioritize funding based on the availability of other clean energy technologies.

The global research group — 85 percent — can largely be achieved through energy-efficient solutions, renewable power and direct electrification, not hydrogen. The remaining hard-to-electrify yet energy-intensive sectors, like commercial transport and heavy industry, are where hydrogen can come in, it argues.

Similarly, Physicians for Social Responsibility said heating homes with hydrogen is a prime example where more efficient and less expensive solutions already exist: heat pumps and electrical appliances.

“It’s not that we’re opposed to green hydrogen,” said Barbara Gottlieb, director of environment and health at the physician-led group, which advocates for protecting the public from climate change. “Rather, we recognize that it’s a really scarce commodity, and therefore, it needs to be reserved for those industries or those needs where there aren’t other available options.”

A lot of electrification can take place at residential levels to remove gas and oil for heating before you get to hydrogen, said Frank Wolak, president and CEO of the Fuel Cell and Hydrogen Energy Association. But many things must happen before massive hydrogen conversions occur, he said

Ultimately, whether hydrogen becomes the preferred fuel to heat homes will depend on economic and regulatory factors, including the availability of future incentives for people to quickly adopt it, Wolak said.

“It doesn’t have to be universal. But as these gas utilities say, ‘I got to find out about this,’ you learn what are the thresholds, what are the safety procedures, what are the impacts on leakage,” he said. “Then you can start to say, ‘What’s the cost-benefit of doing it?’ That will be case by case around the country.”

Hazards and hurdles

Last year, Physicians for Social Responsibility and the American Medical Association against burning hydrogen-methane blends in indoor spaces. They cited research indicating that the mixtures release more nitrogen oxides (NOx) than methane alone, which can worsen pollutant-linked diseases like asthma and dementia.

“Hydrogen ignites more easily and is more explosive than methane, thus increasing the danger of explosions in buildings,” Physicians for Social Responsibility added . “It places lives at risk.”

Dominion Utah has on its website. The company said that after a year of internal testing, it found no adverse effects from blending a lower concentration of hydrogen on the integrity of its pipelines, NOx levels or appliances.

“We don’t feel like there are any health concerns at five percent combustion,” said Andrew Hegewald, a business development manager for Dominion Energy’s sustainability initiatives, when asked for further comment on the criticisms. “It wasn’t so much safety for the end users, more safety on our pipes.”

The internal testing aimed to avoid a potential problem known as “embrittlement,” which experts say can occur when transporting hydrogen in pipelines originally designed for natural gas.

Depending on the type of metal, length of exposure, and its concentration, hydrogen can place stress on the material, raising the risk of cracks and leaks, funded by DOE and its .

The California Public Utilities Commission that found blending up to 5 percent hydrogen with natural gas is “generally safe,” but higher levels bring a greater chance of embrittlement and pipeline leaks. That raises the risk of hydrogen or methane escaping and offsetting the environmental benefits of using green hydrogen.

However, Hegewald said five percent is a good number for blending because it’s “not so large to introduce any safety concerns.”

For companies, blending projects are appealing because they continue to use natural gas infrastructure already in place for hydrogen distribution while progressing on internal emissions-cutting goals. Gas utilities more than three dozen pilot projects to look into the potential of using hydrogen to decarbonize their distribution systems.

Southern California’s main gas provider, SoCalGas, has also a real-world blending demonstration to heat with hydrogen. The utility wants to deliver a hydrogen-natural gas mix to university campus buildings, viewing it as “another way to replace fossil fuels and lower greenhouse gas emissions.”

Besides home heating, hydrogen can be blended into gas pipelines for power generation and other uses.

“Blends allow for the use of existing, installed natural gas furnaces and associated natural gas piping,” said Hegewald. “Customers can continue to enjoy the reliability and efficiency of natural gas with added emissions benefits, without the need for appliance replacements.”

Dominion Utah claims that by starting up on-site green hydrogen production, it will save an extra 110 tons of carbon a year — equal to planting around 5,000 trees.

Hydrogen blends for home heating systems are still mostly natural gas — 95 percent in the case of Utah’s project. While 5 percent green hydrogen “may not seem like a lot, the emissions savings is compounded the longer versatile energy sources such as hydrogen are used,” Dominion says on its website.

Climate advocates worry that such projects are greenwashing and could lock in dependence on gas to keep homes warm, rather than compelling companies to look into fossil-fuel-free solutions.

“In my eyes, it is continuing the status quo,” said Alejandría Lyons, coordinator of the New Mexico No False Solutions, a coalition of climate and environmental justice organizations that opposes all hydrogen development for the time being.

The future of hydrogen in homes

So far, Dominion Utah has paid for hydrogen’s price premium rather than passing along costs to ratepayers with its ThermH2 pilot. It had hoped to use federal dollars to offset those expenses.

The project was part of a regional proposal — formed by the governors of Colorado, New Mexico, Utah and Wyoming — that competed for $7 billion from the administration to build out the nation’s first clean-hydrogen hubs.

It’s not clear why DOE eventually rejected the states’ application when it picked seven other winners last month. Lyons’ coalition had written to the department, for reasons related to health, safety, community engagement, resource scarcity and the belief that projects would entrench fossil fuel production.

ThermH2 originally envisioned four phases and matched timelines to milestones for the hubs. This spring, it left Phase 1, which involved the yearlong safety tests, and moved into Phase 2 with real customers. November’s launch of green hydrogen production is an extension of the same phase, expected to run until March 2025.

Without the hubs’ money, the company is reevaluating the scope of its remaining phases, the final of which would have started in 2030 and prepared the entire distribution system to blend hydrogen by then.

“Our current focus is on the running and completion of the second phase of this project,” Dominion’s Hegewald said. “We remain committed to hydrogen blending.”

One way it may be able to move forward is through established contacts with nearby hubs that were funded through DOE, including in California and the Gulf Coast. The company said it will seek collaboration when “it is mutually beneficial.”

The DOE-backed hubs, meanwhile, are supporting at least two home heating projects, although funding in the program has leaned heavily toward heavy industry and transportation.

By design, the hubs had to embrace funding a bit of everything. The $7 billion pot required DOE to select at least one hub for each of the following purposes: electric power generation, industrial processes, transportation and residential and commercial heating. The idea was to give hubs freedom to tailor their focuses based on regional strengths.

“As a country strategy, it is really interesting because the message that has been sent is wherever there is potential for a use case of that specific demand, the DOE will support it,” Domingues remarked.

When the seven winners were first announced, just one of them — the Heartland Hydrogen Hub in the Upper Midwest — disclosed any interest in residential or commercial heating.

At the time, said the Heartland hub intended to advance the fuel for “cold climate space heating,” and a includes one in Minnesota under Xcel Energy. The diagram shows hydrogen being directed to a local gas distribution company.

Two weeks after the selections, another winner, the West Virginia-centered Appalachian Hub, unveiled a project for using hydrogen in homes. In a late October community briefing, that companies Hope Gas, Watt Fuel Cell and EQT will collaborate to produce natural gas-derived hydrogen for blending in the utility’s distribution system and residential fuel cells.

Other winning hubs, including those in California, the Gulf Coast and Pacific Northwest, said they are not planning hydrogen projects for home heating.

“In Texas, we have more electric buildings, so there’s not a ton of building applications,” said Brett Perlman, CEO of Center for Houston’s Future, part of the winning Gulf Coast hub coalition.

Even so, researchers have suggested that hydrogen for home heating has legs, though a dominant role in the industry.

“We do believe commercial and residential heating will have a future,” said Hector Arreola, a hydrogen analyst for Wood Mackenzie. “It’s definitely smaller than for other applications.”

Some energy experts say the most favorable scenario for heating with the fuel is during extreme cold spells.

During winters, heat pumps work like a reverse air conditioner, pulling heat from the outside air to warm up indoor spaces. As temperatures drop, these devices have to work harder to extract heat and end up using more energy — though newer models claim to operate even in sub-zero conditions.

In such conditions, hydrogen could relieve the overall strain on the power grid, according to supporters.

“There are certain regions, such as those that have colder and longer winters for example, where natural gas heating provides the highest quality reliability, efficiency and affordability over alternative energy sources,” Hegewald said.