Developing an infrastructure for hydrogen buses in London

'Full text:' Imperial College London is examining transition strategies for hydrogen infrastructure in London under a project funded by the UK EPSRC. Technical and economic models are being combined with specific socio-economic analysis to provide insight into some of the most promising options for infrastructure development. This paper presents a comparison of scenarios for the uptake of H2 internal combustion engine (ICE) buses in London, and the infrastructure that might develop for refuelling them, with equivalent scenarios for fuel cell (FC) buses. Due to the greater technical maturity and lower cost of ICE buses, one would expect a more rapid uptake of these buses during the early years than for FC buses; as a consequence of higher rates of H2 bus uptake, the economics are likely to be more favourable to larger production units during these early years. The demand for hydrogen will be higher from the ICE buses, not only due to the greater number of buses, but also the lower efficiency of the engine compared with a fuel cell. Thus the demand for H2 at a bus depot that has been fully converted to hydrogen would be around double that for fuel cell buses. Scenarios for infrastructure development will take into account both this factor and the rate of demand growth in determining the type and sizing of infrastructure components. Presented are results of modelling work on the uptake of H2 buses and on the technical and economic performance of different infrastructures for fuelling these buses. These results include technical analyses of feasible infrastructures, comparisons of the costs of bus ownership and fuelling infrastructure and the effect of different scenarios on primary energy consumption. (author)