Musician Lukas Graham
Vestas Wind Systems A/S

On a warm August evening, Danish pop act Lukas Graham pulled up to his 15,000 person off-grid show at an old military base just outside Aalborg, towards the northern tip of Denmark, with a new form of concert power in tow: electric truck batteries charged up with wind turbine energy.

“We just rolled in with these big batteries. We didn’t need the generators. It just felt so good,” says Graham. For festival fans, outdoor concerts are a chance to appreciate music in natural surroundings, but backstage, gallons of diesel are being burned to power the lights and sound. Graham describes these diesel generators as sounding like “a big-ass car or truck just running on standby.”

“That smell of diesel burning—it’s not here,” Graham adds, speaking from the concert grounds, “which is a very tangible thing. It does change the [backstage] atmosphere completely.”

The climate impact of an outdoor festival can vary by location and size of event. According to a 2018 survey by nonprofit A Greener Festival, the average outdoor concert releases 500 metric tons of carbon dioxide—that’s roughly the same as driving 100 gas-powered cars in the U.S. for an entire year. About a third of a music tour’s climate impact comes from the venue, according to UK data. And a 2019 report by sustainability consultancies Hope Solutions and ZAP Concepts, estimated the UK entertainment industry uses 100 million gallons of diesel for their events each year.

As awareness rises about the climate impact of festivals and touring, musicians are looking for ways to reduce their footprint. Artists like Coldplay, Harry Styles, Billie Eilish, and Pearl Jam have tried eliminating single-use plastic at venues, offering plant-based meals at the concession, or encouraging fans to use low carbon transport to get to shows. But they have also relied in part on carbon offsets to compensate for their tours’ climate impact—a way of balancing out emissions released in one place by trapping the same amount elsewhere (such as through reforestation) which some have criticized as being unreliable and failing to incentivize actual emissions reductions. Graham’s In The Round tour tackles emissions at their source. “I’m just trying to up it a notch,” he says.

The batteries used for his concerts are part of a brand partnership deal with Vestas, a Danish wind turbine manufacturer. They are charged at a substation, with power generated from an onshore wind farm. Vestas claims their batteries reduce up to 98.5% of the roughly 1.5 tons of carbon emissions released during each one of Graham’s concerts, depending on the venue.

Electric truck batteries charged up with wind turbine energy parked outside of a Denmark concert venue. (Vestas Wind Systems A/S)
Electric truck batteries charged up with wind turbine energy parked outside of a Denmark concert venue.
Vestas Wind Systems A/S

To do this, Vestas’ engineering team packed 72 electric truck batteries in two 20-foot navy shipping containers. These were then trucked into each of Graham’s six concert venues on his Danish tour, with recharging stops between shows over a five hour window. Backstage, the shipping container batteries—still on their wheels—sit parked, and a panel located at the back opens up to reveal a sleek touchscreen interface with output sockets that resemble those on generators commonly used to power festivals.

“We have made an interface similar to what is used in these events,” explains Torben Petersen, a Vestas engineer onsite, pointing to the cables snaking along the ground up to the main stage. “It doesn’t require any training to install.”

The batteries worked “with ease” according to the company—a testament to their reliability since the team didn’t bring any backup power. “If for some reason the batteries failed, the stage would go black,” says Lars Christian Christensen, Vestas VP of storage and energy solutions. “If you make a mistake, a lot of people would notice it.”

Diesel generators were, however, still used to power the festival grounds—something that both Graham and Vestas say they would like to electrify in the future. “There’s a lot of these things that you just don’t have the time to do when you’re doing something at this scale,” says Graham. “We’re talking 10,000 to 20,000 people. That’s a lot of toilets, it’s a lot of fridges, it’s a lot of hotdogs, you know?”

Read more: How the Universal Language of Music Can Help Us Solve Our Planetary Problem

Graham grew up in Freetown Christiania, an eco-conscious autonomous community in Copenhagen established in the 1970s when artists and squatters took over an abandoned military base.

“I grew up in a hippie community. We didn’t have a toilet in our bathroom until I was like, six,” he says. The back entrance to Christiania buttresses some of the energy production facilities for the city, including an incinerator. “Right in front of my mom and dad’s house, I could see the chimneys from this big power plant that burns garbage. And right next to that, I saw during the 1990s the first big windmill parks shoot up. It’s a very stark contrast,” Graham says. “As a child, the idea of water or wind moving a wheel or generating something in a turbine, that’s cool. And to me it doesn’t get less cool with time.”

He’s not alone in his thinking. Vestas and Universal Music Denmark, Graham’s label, are in conversation about potentially offering this technology to other artists. “We don’t know anything yet about how we’re going to go forward with all this interest that’s coming our way,” says Sara Chloé Cantor, strategic director for music and brands at Universal Music Denmark. “I can just say that it has really raised awareness.”

Whether it’s for his own shows or just to promote the technology, Graham hopes the shipping container battery packs can be used somehow next summer for outdoor shows, or that a set could be built in the U.S., where they could be brought to festivals like SXSW that showcase both music and technology.

“The batteries work very f-cking well, and they charge pretty quickly too,” says Graham as he wrapped up his Danish tour on Aug. 27. “The software in them is telling us there’s no change in the usage, or in the way they work and the functionality. So that’s pretty awesome.”

While the tour has been a success, Graham acknowledges it’s a drop in the bucket for overall emissions. “It’s still tiny compared to the concert capacity of, say, Europe in the summer,” he says.

Vestas is not, at present, planning to offer a commercial solution that other artists could purchase, though the company says it’s in internal conversations about next steps. “We’re all in on trying to electrify society in general,” says Christensen. “If there’s a commercial incentive then I’m sure our management would have a look at a strategy pointing that way.”

“Several people told me I should make this into a business,” says Graham, adding that this ran against his conscience to profit off of the solution. “I’d rather just be the advocate for something that is a better version of what we had before.”

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