With the low-hanging fruits of transitioning to green gas already addressed, cities are finding the final steps to carbon neutrality increasingly challenging. HOFOR, the public utility company for the Copenhagen area, currently supplies 65 percent of the city’s gas as carbon neutral. The goal is to achieve a 100 percent carbon neutral gas supply by 2025. 

HOFOR and system supplier Biogasclean are testing biological Power-to-Gas technology at BIOFOS’ wastewater treatment plant at Avedøre Holme. The technology can convert biogenic H2C and CO2 from the biogas production of BIOFOS’ wastewater treatment into e-methane. This green methane can be distributed through the existing gas network to areas beyond HOFOR’s own premises, extending the benefits of renewable energy to a broader community. 

By incorporating the biological Power-to-Gas technology alongside existing biogas production, a 66 percent increase in production of green gas from wastewater is anticipated.  The tests have proven to be successful, and the plan is to invest in a full-scale facility. While there may be a marginal increase in gas prices, the long-term benefits of carbon neutrality outweigh the intial costs, ensuring a greener future for Copenhagen.