10142129Hydrogen Efficient fuel cell InteGrated in a High Temperature System (HEIGHTS)ActiveLegacy Department of Trade & IndustryInnovate UKProject HEIGHTS will deliver an aerospace high-temperature hydrogen fuel cell system targeting eVTOL, sub-Regional and Regional aircraft propulsion in addition to Auxiliary Power Unit (APU) markets. The project addresses the key challenge with traditional fuel cell systems -- how to keep the fuel cells at the correct operating temperature without introducing significant drag in cooling systems. In aviation particularly, minimising the heat exchanger size is critical to reduce mass and drag, and to optimise overall efficiency. IE's patented direct water injection technology (Evaporative Cooling -- EC), utilises air cooled condensers with 20-30% smaller frontal area compared to competitor liquid glycol radiators. In project HEIGHTS, IE will enhance this novel cooling approach to unlock a further 30-40% reduction in heat exchanger size. The innovative High Temperature Heat Rejection System (HTHRS) introduces a compressor into the cooling circuit to achieve a condenser hot-side inlet temperature of up to 120degC, while the fuel cell still operates at 80degC. Coupling the HTHRS with IE's patented stack, drives reductions in system size, mass and drag, which unlocks a viable technical route to power dense zero emission aircraft propulsion. HEIGHTS pulls together a UK-based consortium of academia and technology leaders within their respective fields to address these challenges and deliver this next-generation fuel cell system for aviation. The consortium is further strengthened by academic research contributing towards the development of cutting-edge fuel cell health monitoring techniques and the provision of a state-of-the-art aerospace test facility for test and validation. IE and the consortium have the ambition to be a technology leader in zero emission flight, and a leading supplier into this nascent industry.