Danish music festival organizers are offering attendees a simple way to help the environment. And that’s peeing.

Roskilde, the largest music festival in Northern Europe, is held every year in Zealand, Denmark, the Guardian reports. This year’s 100,000 expected attendees won’t just be rocking out to the likes of Florence and the Machine and Pharrell, though. They’ll be contributing to an operation called “From Piss to Pilsner.”

“The huge amount of urine produced at festivals was having a negative impact on the environment and the sewage system,” Leif Nielsen from the Danish Agriculture & Food Council (DAFC) said. Now organizers are hoping to use that pee to fertilize barley used to brew beer.

Festival-goers are being encouraged to pee into a metal trough next to a sign that says, “Don’t waste your piss. Farmers can turn it into beer again.” The urine will then be funneled into special holding tanks and finally spread as a fertilizer over malting barley used to brew beer. The DAFC hopes to collect around 25,000 L of urine from those attending, the Guardian reports.

By 2017, attendees will be drinking beer made from ingredients fertilized by the pee gathered this year, organizers say. Insert your favorite taste-of-beer joke here.

[Guardian]

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