Rolls-Royce AE2100 Hydrogen Test at Boscombe Down. Photo / Steve Smith, Rolls Royce
Rolls-Royce AE2100 Hydrogen Test at Boscombe Down. Photo / Steve Smith, Rolls Royce
Rolls-Royce and carrier EasyJet have made history after the first test-run of a plane engine powered entirely by hydrogen.
On a test site in Wiltshire owned by the UK Ministry of Defence, the engine manufacturer successfully ran a retrofitted Rolls-Royce AE 2100 turboprop using hydrogen fuel. The test produced no waste emissions but water and huge potential for clean air travel.
Following the ground test the partnership has commissioned a series of ‘ground tests’ including a Pearl 15 jet engine modified to run off hydrogen.
Celebrating the first step towards zero-emission flight the partnership is keen to get the engines into aircraft. However, there is still a big challenge keeping the technology grounded.
Hydrogen is far less dense compared to traditional airfuels like kerosene. Earlier this year a report by Airbus said that it would take at least 3,000 litres of gaseous hydrogen to get the equivalent energy of 1 litre of kerosene.
Rolls-Royce AE2100 Hydrogen Test at Boscombe Down. Photo / Steve Smith, Rolls Royce
Rolls-Royce admitted that hydrogen-powered passenger jets may be some way off, but “shorter haul” turbo-prop planes may be the first hurdle they overcome.
“Given volume limitations attached to the storage of hydrogen and the limited power density of fuel cells, for long range, Sustainable Aviation Fuel (SAF) fuelling gas turbines will remain the most likely solution moving forward,” said a release from the programme.
Compressing, storing and flying with pressurised hydrogen gas is a headache for engineers. Airbus is experimenting with liquid hydrogen storage, cooling the gas down to -253°C. Even then the supercooled fuel is only a quarter as dense as traditional aviation fuel. Liquid hydrogen has been used to fuel single use rockets, powering space missions. However the aerospace company says that there is still a long way to go before the tanks meet safety and standards to guarantee the desired lifecycle of 20,000 take offs and landings.
Even super-cooled and compressed liquid hydrogen will take up four times the space of traditional fuels, says Airbus. Photo / Airbus Zero E, Supplied
Then there is the challenge of how and where the hydrogen is produced, another energy intensive process.
The current hydrogen market differentiates between “green” and “black” hydrogen, with black hydrogen being extracted from fossil fuels or created using non-renewable sources. In theory, you can make green hydrogen from water and renewable electricity.
This week’s test of the retrofitted AE 2100 was fed with “green hydrogen” made using tidal energy in the north of Scotland, at the European Marine Energy Centre.
“This is a real success for our partnership team,” said Johan Lundgren, CEO of EasyJet.
The carrier which is partnered with the engine maker aims to have passengers on hydrogen-fuelled flights within the next 30 years.
“We are committed to continuing to support this ground-breaking research because hydrogen offers great possibilities for a range of aircraft, including Easyjet-sized aircraft. That will be a huge step forward in meeting the challenge of net zero by 2050.”
