Decarbonising city bus networks in Ireland with renewable hydrogen

This paper presents techno-economic modelling results of a nationwide hydrogen fuel supply chain (HFSC) that includes renewable hydrogen production, transportation, and dispensing systems for fuel cell electric buses (FCEBs) in Ireland. Hydrogen is generated by electrolysers located at each existing Irish wind farm using curtailed or available wind electricity. Additional electricity is supplied by on-site photovoltaic (PV) arrays and stored using lithium-ion batteries. At each wind farm, sizing of the electrolyser, PV array and battery is optimised system design to obtain the minimum levelised cost of hydrogen (LCOH). Results show the average electrolyser capacity factor is 64% after the integration of wind farm-based electrolysers with PV arrays and batteries. A location-allocation algorithm in a geographic information system (GIS) environment optimises the distributed hydrogen supply chain from each wind farm to a hypothetical hydrogen refuelling station in the nearest city. Results show that hydrogen produced, transported, and dispensed using this system can meet the entire current bus fuel demand for all the studied cities, at a potential LCOH of 5–10 €/kg by using available wind electricity. At this LCOH, the future operational cost of FCEBs in Belfast, Cork and Dublin can be competitive with public buses fuelled by diesel, especially under carbon taxes more reflective of the environmental impact of fossil fuels.