Rolls-Royce and easyJet announced that they have successfully tested a hydrogen jet engine. The ground test marks the world's first run of a modern aero engine on hydrogen.

One of the hardest industries to clean up is aviation because it is hard to make electric planes. The batteries are too heavy for long flights. Airlines and plane manufacturers are working to develop planes that can run on hydrogen and produce water vapor instead of carbon dioxide.

One of the hardest industries to clean up is aviation.

A ground test was conducted in the UK using a converted Rolls-Royce engine. There is a hydrogen production and tidal test facility on Eday in the UK's Orkney Islands. Green hydrogen is the result of wind and tidal power.

Rolls-Royce and easyJet have made commitments to reduce greenhouse gas emissions and are looking to green hydrogen to do so. Green hydrogen is difficult to make and is in short supply. The Biden administration invested heavily in producing more of it.

Most hydrogen today is made using gas. It is difficult to cast hydrogen as a clean fuel because it is only as clean as the energy source that made it. The process of hydrogen production releases carbon dioxide emissions.

The International Air Transport Association says that introducing and certifying new aircraft designs is one of the biggest hurdles for hydrogen- fueled flight. Larger fuel tanks are needed to run on hydrogen. It would take more than one million liters of hydrogen to get the same range as jet fuel.

Green hydrogen seems to be most useful for short flights. According to a 2020 European Union report, hydrogen-powered passenger planes for routes up to 3000 kilometers could be on the market by the year 2035. It is mostly a short-haul airline. More than 400 airlines use Rolls-Royce's business aviation engines. Hydrogen is being researched as a clean aviation fuel by two more of those customers.

The recent ground test may have been a success, but there is still a lot of work to be done. According to the Rolls-Royce press release, Rolls-Royce and easyJet are planning more ground tests before moving on to carrying out flight tests.