Spatially explicit planning of a sector-coupled energy system with hydrogen-related heat recovery for district heating

Recoverable heat from electrolysis, fuel cells, and downstream hydrogen-to-X processes may provide an additional link between energy sectors. However, its system-level role and spatial implications remain insufficiently understood, as previous studies mainly focused on plant-level techno-economic assessments of individual technologies or local district-heating integration. This study addresses this gap using a spatially explicit optimization model of the Netherlands in 2050 to assess how hydrogen-related heat recovery affects the cost-optimal design of a sector-coupled energy system. The model optimizes both capacity and operation of supply, conversion, storage, and transmission technologies across Dutch provinces. Under base case assumptions, the results show that heat recovery reduces total annualized system cost by 2% (1.2 B€/yr), reduces battery capacity from 152 to 130 GWh and heat-pump capacity from 17 to 9 GW, while increasing electrolyzer capacity from 41 to 45 GW and underground hydrogen storage capacity from 33 to 37 TWh. Heat recovery substitutes part of dedicated district-heating supply and increases the use of hydrogen-related heat and hydrogen storage. Spatially, electrolyzer capacity shifts partly from locations mainly favored by renewable availability toward locations where recovered heat can be used in district heating, leading to greater use of hydrogen transmission infrastructure. Sensitivity analysis shows that higher district-heating shares moderately increase the value of heat recovery, while heat transport distance and hydrogen-cavern availability affect the strength of this effect. These findings show that hydrogen-related heat recovery can influence not only local heat utilization, but also technology competition, spatial siting, and infrastructure needs in sector-coupled energy-system planning.