On Wednesday 27 March, the SWITCH field lab of knowledge institute TNO and Wageningen University opened in Lelystad. Here, researchers can test solutions to incorporate wind and solar energy into electricity infrastructure.

It is drizzling and the sky is grey, above the fields in the Flevopolder. A group of people - the journalists in their everyday attire, the scientists tightly dressed in suits - walk around between a few containers on the site. They take turns opening them to show the journalists a battery, electrolyser or transformer.

We are at the SWITCH field lab, a research facility just northeast of Lelystad, belonging to knowledge institute TNO and Wageningen University & Research (WUR). Here, researchers will soon be able to try out how wind turbines, solar panels, electrolysers and battery systems can work together optimally to match energy supply to market demand and make optimal use of the electricity grid. This afternoon, this open-air laboratory will be officially opened.

Full electricity grid

This is not a day too late. Just under ten thousand companies are on the waiting list to be connected to the electricity grid, figures released by Netbeheer Nederland at the request of De Volkskrant in February this year showed. Although this probably includes many 'ghost applications', there is indeed a big problem. In some parts of the country, the grid is simply full, says Netbeheer Nederland. Also, returning power is far from always possible.

This is the biggest challenge of the near future in terms of energy transition, thinks Peter Eecen, Research & Development manager at TNO Wind Energy and one of the experts present today at the opening of the SWITCH field lab.

'We are producing more and more electricity from wind and solar power. But how do we arrange that this power is always available at the desired time and how do we prevent an overcrowded and unstable power grid?'

Solutions

Many solutions to this have already been devised, including large batteries to store energy in times of abundance for when a lot of it is needed all at once, or using the surplus electricity to make hydrogen, which can be transported and deployed at desired times. That just often sounds easier than it is, Eecen explains.

'Devices to make hydrogen via electrolysis, for example, simply exist. But if you run these on green electricity, and only want to use them when there is too much of it for the grid, such a device goes on and off again and again. That is bad for the efficiency and durability of the machine. So we want to come up with something on that.'

Researchers from TNO and Wageningen University & Research/ACRRES working on such issues can now visit the SWITCH field lab.

Devices

On the site, there are six wind turbines, each with a capacity of 15 kilowatts, an electrolyser with a capacity of 25 kilowatts, a battery of 50 kilowatts and solar panels with a combined capacity of 60 kilowatt peak (which is the maximum power at standard conditions). There are also some 'free spaces' available, where new technological innovations can be added to this energy grid at scale.

Solar and wind power generation can be directly linked to the electrolyser and battery. This provides the opportunity to test a wide variety of configurations in the field and develop control strategies.

All power comes together in a switching container for this purpose, and there is a transformer that can adjust the voltage before the power possibly enters the public grid. The latter is a choice option: either on-grid or off-grid can be used. There is also metering equipment that tracks and stores weather conditions.

All scales

At the SWITCH field lab, applications are tested for any scale, the researchers stress. This includes looking at the possibility for local networks at (farming) companies or clusters of companies, which want to generate their own power and not depend on the national electricity grid. This week, The Engineer already wrote about this: the rise of flexible local energy markets (LEMs).

'That actually applies to us ourselves,' says Chris de Visser, who is involved in the SWITCH field lab as a researcher at WUR's Application Centre for Renewable Resources ACRRES. 'We have eight charging stations for cars here on the site, which in addition to SWITCH also houses a test centre for sustainable agriculture and animal husbandry. And we want to install a heat pump to heat the greenhouses. But we only have a 250-kilowatt connection, so we have to come up with something clever ourselves too.'

First projects

The first project SWITCH is now being used for is the electrification of European ports, including that of Rotterdam. MAGPIE, is the name of this project. 'When ships have sailed in, in order to unload everything, shore power is needed for the cranes,' says Eecen. 'That takes a lot of power in a very short time.' Drawing that power from the grid is not an option for the time being. For grid stability, it would be better to use renewable energy rechargeable batteries for this purpose. but can they handle that? And how do you regulate that so that they have enough power at exactly the right times?'

Combining wind and solar energy at sea is another topic that is receiving attention. Can they go through the same cable, and how do you smear the peaks - especially if they suddenly occur with wind and solar at the same time?

The SWITCH lab is a playground for energy researchers, where solutions to such questions can be tried out from today.

Opening photo: TNO