Is hydrogen a clean energy source?

It depends. Hydrogen does not release greenhouse gas emissions when it is used, so, similar to electricity, what really matters from a climate perspective is how the hydrogen is produced. That can range from very dirty to very clean. The vast majority of hydrogen used today is made from natural gas and produces a lot of greenhouse gas (GHG) emissions. Hydrogen produced in this manner is often referred to as “gray hydrogen.” There are also methods of producing “green hydrogen,” most notably by using renewable electricity to break water into hydrogen and oxygen through a process known as electrolysis. But, regardless of how hydrogen is produced, emerging research has found that – just like natural gas – hydrogen that leaks directly into the atmosphere is damaging to the climate.

What is hydrogen’s current role in our economy?

Today, hydrogen is used in industrial processes like oil refining and fertilizer production. In recent years, there has been expanded focus on the potential for using hydrogen to help decarbonize other sectors of the economy including power generation, transportation, and the natural gas distribution system. The question of whether to blend hydrogen into the natural gas distribution system to reduce the overall GHG emissions associated with using natural gas has been a particular hot button issue across the country, and particularly in the northeast.

Why is hydrogen suddenly a hot topic in the Northeast?

Many of the gas utilities in the Northeast have proposed hydrogen blending as a core strategy in their decarbonization plans and some are actively pursuing hydrogen blending pilot projects. The appropriate use of hydrogen was a key point of debate in the Massachusetts Future of Gas docket and four northeastern states (New York, New Jersey, Connecticut, and Massachusetts) have partnered to pursue a portion of the $8 billion of funding available through the Department of Energy to create a “regional hydrogen hub.”  Hydrogen is a central point of discussion in the currently underway updates to Connecticut’s Comprehensive Energy Strategy and Connecticut recently formed a Hydrogen Task Force to study hydrogen’s role in the state’s economy and energy infrastructure. Hydrogen will also undoubtedly be a focal point in Rhode Island’s own “Future of Gas” docket that recently kicked off.

What are the key problems and limitations associated with hydrogen?

Even if hydrogen is “green” (i.e., produced with 100% renewable electricity), it still faces a number of issues and limitations. Perhaps most importantly, most experts agree that hydrogen can only safely replace 7% of the total energy flowing through the gas distribution system, dramatically limiting any potential climate benefit of hydrogen blending. We still need to decarbonize  the other 93%. How? Gas companies have proposed replacing the remaining natural gas with so called “renewable natural gas” which is extremely problematic.

Additionally, the process of producing green hydrogen is inefficient and requires a huge amount of renewable electricity. As a result, for most sectors of the economy, it makes more sense to use clean electricity to “directly electrify” those sectors, rather than adding the inefficient middle step of converting that clean electricity to hydrogen. For example, using clean electricity to run a heat pump for heating a home is about five times more efficient and significantly more cost effective than using that same clean electricity to produce green hydrogen, blend that hydrogen into the gas system, and then burn that hydrogen in a boiler.

Because green hydrogen requires so much clean electricity to produce, producing green hydrogen at scale would require a ton of land to site the wind turbines and solar panels. We simply will not have enough land to produce green hydrogen at the scale necessary to decarbonize the whole economy. The limited green hydrogen we will have should be allocated to the sectors of the economy that are hardest to electrify, like aviation, shipping, and certain industrial processes. It is critical to use this limited resource strategically, and not waste it in sectors of the economy that are relatively easy to electrify, like building heating and passenger vehicle transportation.

Are there safety concerns associated with hydrogen?

Hydrogen does present unique safety challenges. It is the smallest molecule in the universe and is prone to leaks, highly combustible, and burns with a nearly invisible flame. So, while hydrogen is relatively safe in an industrial facility where trained professionals can constantly monitor the equipment, it does pose significant safety risk when you consider scenarios like people burning hydrogen in a furnace at their home.

What are the alternatives to hydrogen and why should we use them?

It is going to depend on the sector. As mentioned before, there are sectors of the economy that are exceedingly difficult to electrify such as shipping, aviation, certain industrial end uses, and chemical production. We are almost certainly going to need some amount of green hydrogen to decarbonize these sectors, but for many parts of the economy the main alternative is direct electrification using technologies like heat pumps and electric vehicles. For cars and home heating in particular, direct electrification is the superior alternative from basically any angle you can think of: Cost, efficiency, safety, and overall practicality.

Why should people be concerned about the gas company proposals to blend in hydrogen?

Direct electrification of homes using heat pumps and electric water heaters is a more cost-effective and safer means to decarbonize homes and save consumers money. Allowing gas utilities to blend hydrogen into the gas distribution system is a short-sighted decision that will only marginally reduce greenhouse gas emissions, cost ratepayers money, and distract from the more practical solution of electrification.

How do Acadia Center’s CLEAN-E and Beyond Gas Initiatives address these concerns?

Acadia Center is actively engaged in discussions around hydrogen in various forums  in Massachusetts, Connecticut, and Rhode Island. Acadia Center is leveraging our technical expertise related to hydrogen and our analytical capabilities to question modeling assumptions through independent quantitative analysis, develop detailed public comments, present to state agencies, and educate partners. Acadia Center is also a member of the Connecticut Clean Energy Task Force Hydrogen Uses Working Group. Throughout all these processes, Acadia Center is providing technical analysis and research to demonstrate the limitations of using hydrogen in the gas distribution system and the benefits of electrification paired with energy efficiency.

How can people act on this and push for renewable, efficient sources of energy?

There are a few ways for people to get involved. You can write a letter or call your congressperson and advocate for hydrogen to be left out of the easy-to-electrify sectors like home heating and light-duty transportation. Additionally, weatherizing and electrifying one’s home with heat pumps and electric water heaters would lower demand for natural gas. The Inflation Reduction Act has made weatherizing our homes far more affordable, and you can learn more about that here.


For more information:
Ben Butterworth, Director of Climate, Energy, and Equity Analysis,, 617-742-0054  ext. 111