Electro-methane: integration aspects and cost estimates

Paper i proceeding, 2018

One way to decrease the emissions of greenhouse gases from the transport sector is to use renewable fuels such as biogas either produced from anaerobic digestion of e.g. household waste or via gasification of woody biomass. Both processes give raise to excess biogenic CO2, which can be utilized to produce electro-methane. If renewable electricity is used to produce the hydrogen needed, to form electro-methane, the electro-methane is entirely renewable and fully blendable with biogas. The aim of this study is to calculate the production cost and assess if there are conditions under which electro-methane are cost-competitive to fossil natural gas or biogas. We find that there are circumstances when electro-methane can be produced at lower cost compared to the market price of natural gas as well as biogas, however not in the base case. In a future optimistic scenario, a production cost lower than the market price of natural gas can be found for electricity prices of 10-20 €/MWh combined with an investment cost of 100 €/kWel for the electrolyser, where the latter must be judged as an extremely optimistic assumption. Production costs equal or lower than the market price for biogas can in the future scenario be found for electricity prices between 10-30 €/MWh also for current electrolyser investment cost (500 €/kWel). We judge these circumstances  realistic.