Finnish city plans to use heat from sewage to achieve net zero emissions

Turku, Finland, has cut its emissions by more than 50%, and is now looking to achieve net zero emissions by using industrial heat pumps to extract energy from waste flowing from the city's drains and sewers, the Thomson Reuters Foundation reported.

Kakolanmäki wastewater treatment plant. Photo: Turun seudun puhdistamo
Kakolanmäki wastewater treatment plant. Photo: Turun seudun puhdistamo

Turku is Finland’s oldest city, the article states, and the Kakolanmäki wastewater treatment plant is underground in a cavern beneath the Baltic Sea.

Sewage sludge is also trucked from the plant to an industrial facility to produce biogas, a replacement for natural gas, according to the article.

Kakolanmaki, a 130-million-euro wastewater plant, generates enough hot water to heat homes for 12,000 people, Reuters reported.

The plant produces almost 10 times as much energy as it consumes and has halved its annual carbon dioxide emissions since 2017, Jarkko Laanti, a manager at Turun seudun puhdistamo Oy, the company that runs the plant, told Reuters.

"Money smells, you know," Turku Mayor Minna Arve said of earnings from the Kakolanmaki wastewater plant, which opened in 2009, Reuters reported. Officials from as far off as China have visited to learn about its technology.

In 2018, the Nordic Investment Bank announced it and Turun seudun puhdistamo Oy signed a 15-million-euro loan agreement to modernize the wastewater treatment plant.

The project separated the wastewater and storm water discharge systems, enabling the wastewater treatment plant to utilize its full wastewater treatment capacity during extreme weather conditions. It reduced the overflows of untreated wastewater as well as the nutrient and microbiological load on the environment.

Related News

From Archive


{{ error }}
{{ comment.comment.Name }} • {{ comment.timeAgo }}
{{ comment.comment.Text }}