Roskilde Festival: Electric cars replace generators at Food Court

Friday 05 Jul 19

Electrical Engineering programmes

Three electric cars at Roskilde Festival’s Food Court ensure ample electricity to cope with peak loads without using generators.

Each day at the festival, more than 100,000 people crave hot food and cold drinks.

This of course results in a large power consumption, but due to the festival’s relatively temporary conditions, its connection to the power grid is not sufficiently strong to meet those needs all the time. The consequences of power overconsumption are overloaded cables and blown fuses, breakdowns, and no food.

That is why expensive diesel generators with heavy carbon footprints are necessary to cover the needs—especially at peak hours for power consumption during the day. But the festival’s desire for sustainability naturally entails an ambition to reduce generator power consumption.

At the festival’s Food Court, which is a hall at the festival with approximately 20 food stalls, high power consumption is a particularly difficult challenge. But it has now been three years since they moved away from the generators completely, explains Thomas Malthesen, who is responsible for the Food Court:

“A lot of the time, we are right on the edge of what the power grid can provide. But especially from 1 to 3 p.m. and again from 6 to 9 p.m. there are a lot of people who are buying a lot of food,” he says.

“Nevertheless, we have abandoned the generators. Instead of keeping them to supply us with the additional power we need, we now have three electric cars placed behind the Food Court, that give us a little extra power.”

The cars were installed by three students studying Electrical Engineering at DTU. The method they use is called ‘peak shaving’, explains Ole Batting:

“In short, we charge the electric cars when the Food Court doesn’t use as much power, and then discharge them again when consumption ‘peaks’ and there is a need for additional power.”

The slightly longer explanation is that the electric cars are connected to charging stations. The cars are charged at those times during the day when the Food Court is at a relatively low power consumption. The advantage of the type of cars used is that they can be discharged, which means that they—when the power consumption at the Food Court is particularly high—supply some of the stored power directly into the internal power system.

In this way, you ‘shave off’ the peaks of the consumption, so the need for power from the grid becomes more constant. It is this method, among other things, that has enabled the Food Court to run without generators for the past few years.

The project has been ongoing for several years, because the system requires individual adaptation of the charging stations. It will, however, slowly be scaled up—and this year, the number of electric cars has been increased to three. The objective of this year’s festival is to make the ‘peak shaving’ even more efficient, to predict consumption, and primarily to ensure that the cars do not discharge completely. But the students see great potential in scaling up the project even further:

“Our dream is for Roskilde Festival to provide free parking for electric cars. We would be able to utilize such a battery park to regulate the festival’s electricity consumption to an even greater extent by moving some of it to periods with less pressure on the power grid,” says Nilas Klausen, adding that as long as you do not charge or discharge completely, it has no measurable effect on the battery’s life.

Facts about the Roskilde Festival/DTU collaboration

  • DTU and Roskilde Festival entered into a partnership in the spring of 2010.

  • The purpose of the partnership is for DTU students to do who voluntary, unpaid work on various projects that tackle a technical issue at Roskilde Festival.

  • In cooperation with a DTU supervisor, the students design a project related to one of the many technical challenges found at the Festival. They then use the festival week to both conduct theirs studies and present the project to festival-goers and other interested parties.

  • The project is worth five ECTS credits if the student follows up with a detailed technical report, which is marked by an the supervisor.

  • This means that for approximately 100 DTU students, Roskilde Festival will not just be about music and entertainment, but also about challenging their academic skills and trying out new ideas in practice.

  • Among other things, the collaboration has given the DTU students behind the start-ups Volt, DropBucket, Cutlab, PeeFence, and Allumen a platform for testing their technology before they started their enterprises.