Hydrogen could unlock green potential of German sewage treatment plans – industry

Sewage treatment plants could unlock their clean power potential by producing and using hydrogen while treating wastewater, business daily Handelsblatt reports. Wastewater treatment is usually the municipalities’ largest single energy consumer, while at the same time they generate useable energy in the form of gas, electricity and heat. The plants could either obtain hydrogen from the gas that forms in the digestion towers, splitting carbon dioxide (CO2) and methane (CH4), or produce hydrogen through electrolysis, where water is split into hydrogen and oxygen. The oxygen could then be used to purify the water, a process which is usually done by blowing air into the wastewater, and can account for over half of electricity consumption, Markus Schröder, vice president of the German Association for Water, Wastewater and Waste (DWA), told the newspaper. "With pure oxygen from our own electrolysis, this step becomes much more efficient," Schröder said, warning that a shortage of electrolyser manufacturers, rising device prices, and a lack of trained workers to navigate the technical processes are all hurdles to implementation.

Sewage treatment plants across the EU will have to move towards energy neutrality by 2040, according to a revision of the Urban Wastewater Treatment Directive, which means they'll have to significantly reduce their energy consumption and produce electricity from renewable sources. Subsidies and streamlined approval procedures were both important for the conversion of wastewater treatment plants, Schröder said.