Green hydrogen is a versatile, storable, potentially zero-carbon fuel source that has been hailed as a solution for countries to reach their net zero targets. It produces just heat and water as by-products when burned or used in fuel cells, making it a highly attractive alternative to fossil fuels.
Traditionally, green hydrogen is produced through gas electrolysis, using electricity to split molecules of water into hydrogen and oxygen gas. In contrast, the Colorado team's 'thermochemical' approach uses heat generated by solar rays to complete those same chemical reactions.
In the new study, the researchers demonstrated that they can leverage iron-aluminate materials to conduct these reactions at elevated pressures, allowing the team to more than double its production of hydrogen.
The team's findings could facilitate the first commercially viable method for producing syngas, a mixture of hydrogen and carbon monoxide that can be converted into fuels such as gasoline, diesel and kerosene.
The findings could open the door for more sustainable energy use in industries such as transportation, steelmaking and ammonia production.
"The way I like to think about it is some day when you go to the pump you'll have, for example, unleaded, super unleaded and ethanol options, and then an additional option being solar fuel, where the fuel is derived from sunlight, water and carbon dioxide," said Kent Warren, one of two lead authors of the new study. "Our hope is that it will be cost-competitive to the fuels sourced from the ground."
SAF-IC facility / University of Sheffield
Image credit: University of Sheffield
In the UK, researchers at the University of Sheffield are also working towards expanding hydrogen production, with a focus on the aviation industry.
The university's Sheffield's Energy Institute has announced its plans to install a new hydrogen electrolyser, which is able to produce hydrogen by splitting water into hydrogen and oxygen. The equipment will be used in research to develop and test new hydrogen-based sustainable aviation fuels (SAFs).
The facility would allow the university to produce nearly 140Nm3 per hour of green hydrogen with storage capacity of 1450Nm3 – more green hydrogen than any other UK research centre.
"In order to drive forward a decarbonised future, we must understand more about the possibilities and capabilities of green hydrogen, particularly with regards to sustainable aviation fuels," said Professor Mohamed Pourkashanian, director of the Institute. "With this new electrolyser at our SAF-Innovation Centre facility, we can work with industry and fellow academics to discover and demonstrate the best way to make a hydrogen economy, and a greener future, a reality.
"We are thrilled to have the capacity to produce the green hydrogen in our site, so that our research and development into SAFs (especially via Power-To-SAF), industrial fuel switching and decarbonisation can continue."
The UK government is consulting on new plans to mandate that all new boilers can generate heat from hydrogen instead of gas from 2026, as part of a set of initiatives aimed at helping households save on energy bills.
The decision goes against a recent review of more than two dozen independent studies, which concluded that hydrogen will not have a major role in the future of heating homes across Britain.
