LH2GT

A consortium led by Rolls-Royce, including Cranfield University, easyJet, Heathrow Airport, MTC, Reaction Engines, UCL and University of Oxford is developing gas-turbine control system technologies that will enable aircraft engines to operate on liquid hydrogen. The UK government has a 10 Point Plan for a Green Industrial Revolution, and Jet Zero which pushes forward sustainable air travel is one of its goals. Similarly, the Aerospace Technology Institute has called on the UK aviation industry to prioritise sustainability and lead action on environmental imperatives. Transition to alternative energy sources to today's kerosene is regarded as one of the technology priorities, and hydrogen is one fuel that could power aircraft in the coming 10-15 years. Particularly, development of a hydrogen-fuelled gas turbine combustion system has been identified as a key enabler for zero carbon emission flight, as gas turbine powered aircraft currently account for 96% of today's aviation carbon emissions.

Achieving this vision is far from easy. Despite the advantage of being a very clean fuel, producing almost pure water as an exhaust product, hydrogen unfortunately has a very low energy density compared to kerosene, meaning that the fuel will have to be in the form of a cryogenic liquid to enable aircraft to fly any appreciable distance. The extremely low temperature of liquid hydrogen, -253 °C, is an incredibly harsh environment for the engine components, and many technological challenges will have to be overcome to produce a hydrogen-powered gas turbine that has the same exacting requirements of quality, performance, reliability and safety as today's engines.

The project, named LH2GT will develop the technologies to control and transport the fuel from the aircraft's liquid hydrogen fuel tank to the engine combustor, including cryogenic pumping, fuel metering, system thermal management, intelligent control systems and component life optimisation. Additionally, LH2GT will carry out a techno-economic analysis of the impact of the introduction of the technology to help inform component design requirements. The technology developed here will be equally applicable to fuel cell as well as gas turbine powered aircraft, which opens the possibility of further improvements in aircraft fuel efficiency in the future. Over a timescale of three years, the project will culminate in a working demonstration of the fuel system.

This exciting project is jointly funded through contribution from the project partners and UK government agencies, BEIS, Innovate UK and ATI.