Britain’s Rolls-Royce has said it has run an aircraft engine on hydrogen in what is thought to be a world first for the aviation industry, which is considering using the fuel to decarbonise air travel.
Key points
- The ground test, using a converted Rolls-Royce AE 2100-A regional aircraft engine, used green hydrogen created by wind and tidal power.
- Hydrogen is one of a number of competing technologies that could help the aviation industry achieve its goal of becoming net zero by 2050.
- Although hydrogen is meant to be a green fuel, it is produced using electricity, and generating that electricity can involve burning of fossil fuels.
- The ground test used green energy to produce green fuel created by wind and tidal power.
Challenges
- Hydrogen produces only water when it burns – as a possible energy source for some flights, although many analysts have serious doubts over whether it could ever be viable for longer journeys.
- For the same weight, hydrogen can provide nearly three times higher energy than gasoline.
- As per one calculation, a Boeing 747 jumbo jet would require more than 1m litres of hydrogen to deliver the equivalent range of 250,000 litres of jet fuel.
- Fuel tanks of that size – which would also have to be kept at high pressure – would probably require a complete redesign of the plane.
Types of Hydrogen energy
- Blue hydrogen is when natural gas is split into hydrogen and CO2 either by Steam Methane Reforming (SMR) or Auto Thermal Reforming (ATR), but the CO2 is captured and then stored. As the greenhouse gasses are captured, this mitigates the environmental impacts on the planet.
- Grey hydrogen has been produced for many years. It is a similar process to blue hydrogen – SMR or ATR are used to split natural gas into Hydrogen and CO2. But the CO2 is not being captured and is released into the atmosphere.
- Green hydrogen – also referred to as “clean hydrogen” – is produced by using clean energy from surplus renewable energy sources, such as solar or wind power, to split water into two hydrogen atoms and one oxygen atom through a process called electrolysis.
