Mainspring among the 12 winners of BloombergNEF's annual award for potentially game-changing innovation in climate solutions

Hydrogen, the most abundant chemical element in our world, emits no planet-warming gasses when burned, presenting a tantalizing solution for hard-to-abate sectors like shipping.

The batteries needed to propel a container ship would be so heavy and bulky, it wouldn’t make economic sense. Steelmaking and other heavy industries often rely on fossil fuels or high carbon minerals not just to produce intense heat, but to create a chemical reaction.

So-called “green hydrogen” can serve as a feedstock for fertilizers and chemicals, a source of heat for steel or aluminum production, or a fuel for heavy transport, particularly when converted into derivatives like ammonia, a liquid that can be transported using existing infrastructure and equipment.

There are different ways to make hydrogen, including from fossil fuels. But green hydrogen is made by splitting water using industrial-scale electrolyzers in a process powered by renewable energy.

Despite its potential, hydrogen has played a small role in the energy transition so far. That’s because it’s still relatively expensive to make, store and transport. And despite its potential versatility, most machines and industries aren’t adapted to use it. With major subsidies for hydrogen set to kick in from the US climate bill, all that could change. BNEF awarded three startups working to make green hydrogen mainstream.

Mainspring has created a new type of power generator that can run on hydrogen, ammonia, biogas and other fuels. It sells its generators to commercial and industrial customers that need backup power as well as to utilities. The so-called linear generator’s biggest selling point is flexibility — operators aren’t locked into a single decarbonization route and can switch fuels depending on cost and availability. The company says that today, each unit of power generated using the linear generator rather than US grid power would save 1,400 tons of CO2 per year.

Mainspring Energy launched its first commercial project in 2020 and has deployed dozens of units at customer sites to date.