LOHCell – Simplified on-demand utilisation of renewable energy stored by a virtual hydrogen carrier

Project Description

A smooth transition from fossil fuels to renewables is complicated by frequent mismatch between times and locations of maximum renewable energy generation and demand. Accordingly, achieving targets for decarbonising the energy and transport sectors are infeasible without advances in energy storage technology. The conversion of electricity to hydrogen via water electrolysis is commonly presented as part of the solution, since the energy can be readily liberated when required. However, implementation is frustrated by difficulties related to the storage, handling and transport of gaseous hydrogen. This project seeks to circumvent this by enabling energy storage through organic liquids, which may be considered as 'virtual hydrogen carriers'. Electrolytically generated hydrogen can be reacted with unsaturated forms of these liquids to form hydrogen rich, Liquid Organic Hydrides (LOHs). LOHs can be stored and transported with infrastructure currently used for gasoline, and reconverted to hydrogen for subsequent conversion to electricity. The efficiency and practicality of this scheme would be improved if LOHs could be directly converted to electricity, without the need for first reverting to hydrogen. This project seeks to accomplish this through a Direct LOH Fuel Cell, which simultaneously regenerates the unsaturated liquid. Previous attempts to realise this vision have been hampered by the inadequacy of traditional fuel cell catalysts. Owing to their performance in related catalytic systems, more sophisticated catalysts based on N4-metallomacrocycles will be trialled for the oxidative dehydrogenation of LOHs, with the optimum combination of compound anodic electrocatalyst and LOH being employed in a prototype fuel cell.