Summer is the time for music festivals, but almost all of them in Europe use polluting diesel generators to pump out the beats and light the sky with lasers.
As a sustainable alternative, over the past two years researchers at Eindhoven University of Technology (TU/e) and nine companies have developed a 21m-high, foldable tower festooned with solar panels, with a vertical wind turbine on top.
Easily transportable, and requiring less than a day to set up, the "Green Energy Mill" (GEM-tower) is designed to power festivals renewably.Â
On 5 August, their prototype was fully erected on the TU/e campus for the first time, ahead of the first practical test that will take place next week at Pukkelpop music festival in Hasselt, Belgium.
The Ultra Europe music festival, Split, Croatia, 2016 (Ultrafan123/CC BY-SA 4.0)
For years, the polluting nature of festivals has bothered Faas Moonen, TU/e’s associate professor of Innovative Structural Design.
With a €2.3m subsidy from Interreg Europe, he began work in 2017 on a sustainable alternative, appointing a postdoc and three PDEng researchers to help him.Â
Nine companies, including the Pukkelpop festival organisers and music promoter Eurosonic Noorderslag, joined the mission (see credits at bottom).
"Eventually, a whole group of towers will have to travel around the European festivals and provide them with 100% sustainable energy," says Moonen. "I also hope that their striking appearance will make festival goers more aware of sustainability."
A portable puzzle
The team’s challenge was combining different renewable power-generating techniques in a way that was effective, safe, portable and attractive.Â
"That was quite a puzzle," said Moonen.
Although the precise yield of the tower has yet to be proven through tests, it should be able to generate electricity for 261 days per year.
At the bottom is a three-metre-high battery pack that can store 90kWh of electricity.
Thanks to 300 hinged joints fixed by 542 bolts, the 14-metre-high, 3500kg steel structure folds down into a mass just a metre high (Bart van Overbeeke)
Home-grown solar collectors
Most of the energy is generated by a vertical wind turbine weighing 700kg installed at 18m height, where the wind is known to blow harder.
If there’s no wind, 144 flexible, thin-foil solar cells bolted all the way up each side of the tower pick up the slack.Â
To please the eye, TU/e developed 40 coloured Luminescent Solar Concentrator panels, which have the added benefit of generating power even in cloudy conditions, as they catch light and transfer them to the panel’s edges, where solar cells convert the concentrated beams into electricity.Â
They were developed in the research group of Prof. Michael Debije in TU/e’s Department of Chemical Engineering and Chemistry.Â
Said Moonen: "In both the shade and in the sun, they provide energy. Even on a completely cloudy day, they continue to produce electricity."
For good measure at Pukkelpop, the research team is supplying 72 large, flexible solar cells, which the festival organisers can put on the roofs of their food stalls and other structures, and these connect to the tower’s battery pack.
GEM-tower’s turbine (Bart van Overbeeke)
Power mill in a suitcase
The team decided GEM-tower had to be foldable to make transport more sustainable.Â
So, thanks to 300 hinged joints fixed by 542 bolts, the 14m-high, 3500kg steel structure folds down into a mass just a metre high.
It takes less than a day to assemble, and a crane is required, but the team intends for the next version to unfold automatically at the push of a button.
Once extended, the tower is free standing thanks to its base comprising 2.7 cubic metres of concrete.
This year GEM-tower will be tested, ahead of planned full operation at festivals in 2020.
"We will then start building a new tower which will generate even more power and can also be folded out automatically," said Moonen.Â
"In addition to the towers, we also want to keep our eyes open to other forms of sustainable energy generation. My dream is to eventually provide all kinds of large-scale events – in both summer and winter – with sustainable electricity through a network of batteries, towers, solar cells and other sustainable innovations."
Project leader Faas Moonen is supported by PDEng researchers Floor van Schie, Patrick Lenaers and Marius Lazauskas, and postdoc Ester Pujadas-Gispert.
Nine partners in the project include: IBIS-Power, Double2, Pukkelpop, Off Grid Energy Limited, Dour, RPS, Eurosonic Noorderslag, Flexotels and ZAP.
Visit theÂ websiteÂ for more information.Â
Top image: aerial view of GEM-tower (Bart van Overbeeke)