Power-to-gas plants in a future Nordic district heating system

Power-to-gas (P2G) technology has been suggested as one way to balance the variability of renewable power generation and decarbonize the transport sector. This paper studies the application of P2G plant in a real Finnish municipal district heating system in a future situation where the European power and district heating sectors have been decarbonized. From the point of view of the district heating company, the P2G plant can act as fuel producer, CO₂ sink and heat source. The district heating unit commitment (DHUC) model was used to optimize the full-year hourly resolved operation of a CHP CCS plant, heat boilers, heat pumps, P2G plant and heat storages. Capacity optimization of most plants was also done. The hourly power price variability was obtained from regional unit commitment and economic dispatch simulation of the North European region. We find that a P2G plant may be profitable in the system, starting with SNG value of 70 €/MWh and depending on the specific investment. The regional simulations show that the market value of SNG is greater than this, and we conclude that P2G is a viable option.