Retail giant Hennes & Mauritz, more commonly known as H&M, is helping the utility transition away from coal via its moldy or otherwise unsaleable clothing.

The multi-fuel power and heating station in Västerås, central Sweden, is aiming to be completely fossil-fuel free by 2020. It’s the largest station of its kind and Sweden claims it’s one of Europe’s cleanest. To kick its coal habit, the station is turning instead to other burnable materials including recycled wood, rubbish and yes, clothes.

“Our goal is to use only renewable and recycled fuels,” Jens Neren, head of fuel supplies at the utility company which owns and operates the Västerås plant, told Bloomberg.

The Västerås plant has been burning refuse from a nearby town. Earlier this week, the unorthodox inclusion of H&M clothes in its power-generating heap was uncovered by a Swedish national television program.

Johanna Dahl, head of communications for H&M in Sweden, told Bloomberg that the company allows only the burning of clothes which are no longer safe to use.

“It is our legal obligation to make sure that clothes that contain mold or do not comply with our strict restriction on chemicals are destroyed,” she said.

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The Västerås plant has burned around 15 tons of old H&M merchandise so far this year, compared with about 400,000 tons of rubbish, Neren told Bloomberg.

Sweden has one of the world’s greener energy generating grids, and has invested in bioenergy, solar power, electric buses and subsidies for green cars. In 2015, the Scandinavian country announced an ambitious aim to become one of the first nations in the world to end its dependence on fossil fuels. According to the Swedish government, the country has already heavily reduced its reliance on oil, which accounted for 75% of the energy supply in 1970, and now makes up a 20% share.