How much heat can we grow in our cities? Modelling UK urban biofuel production potential

Biofuel provides a globally significant opportunity to reduce fossil fuel dependence; however its sustainability can only be meaningfully explored for individual cases. It depends on multiple considerations including: life‐cycle GHG emissions, air quality impacts, food versus fuel trade‐offs, biodiversity impacts of land use change, and socio‐economic impacts of energy transitions. One solution that may address many of these issues is local production of biofuel on non‐agricultural land. Urban areas drive global change, for example they are responsible for 70% of global energy use, but are largely ignored in their resource production potential; however under‐used urban greenspaces could be utilised for biofuel production near the point of consumption. This could avoid food versus fuel land conflicts in agricultural land and long‐distance transport costs, provide ecosystem service benefits to urban dwellers, and increase the sustainability and resilience of cities and towns. Here, we use a GIS to identify urban greenspaces suitable for biofuel production, using exclusion criteria, in ten UK cities. We then model production potential of three different biofuels: Miscanthus grass, short rotation coppice willow and short rotation coppice poplar, within the greenspaces identified and extrapolate up to a UK‐scale. We demonstrate that approximately 10% of urban greenspace (3% of built‐up land) is potentially suitable for biofuel production. We estimate the potential of this to meet energy demand through heat generation, electricity, and combined heat and power (CHP) operations. Our findings show that, if fully utilised, urban biofuel production could meet nearly a fifth of demand for biomass in CHP systems in the UK’s climate‐compatible energy scenarios by 2030, with potentially similar implications for other comparable countries and regions.