Denmark and many other countries aim to significantly increase the share of renewable energy in their energy systems, but face the challenge that solar and wind power generation can not be controlled in the same way as fossil power plants.

This challenge will grow as more and more fluctuating renewable energy is connected to the grid and the potential for cheap energy storage will therefore grow in tandem. With its focus on cheap energy storage, the ORBATS project will be part of the solution to this challenge.

The ORBATS project is a collaboration between DTU Energy, Vestas, VisBlue, Aarhus University, Lithium Balance and Harvard University.

Traditional batteries, as we know them from your mobile phone or laptop, consist of relatively expensive solids in which the energy is stored, which means that when saving twice the amount of power you need to have a battery that is physically is twice as large.

To solve this physical challenge, ORBATS will develop so-called flow batteries where the energy is stored in a fluid outside the battery itself.

If you need more capacity, you can only purchase a larger storage tank and pour more fluid without having to make the battery bigger. Flow batteries can work for energy storage and, for example, in the smaller energy networks, override diesel generators that are otherwise used as backup power.

For current batteries, vanadium compounds have been used to save energy, which has made the batteries expensive.

ORBATS will therefore replace the expensive element of vanadium and instead use sustainable organic materials. The project will not only develop the new materials, but also the specific management strategies needed to optimize the performance of the new batteries. The new battery type must be demonstrated in a prototype of 5-25 kilowatts.

– Water-based flow batteries have all the potential to become a crucial piece in a sustainable energy system with a high need for energy storage. I am very proud that we have managed to assemble such a strong project team for the task. With the strong industrial participation, there will be a short distance from the new solutions that we as researchers develop for use, says lecturer Johan Hjelm from DTU Energi, who heads the project.

"Vestas works with a number of partners to develop innovative solutions that will reduce the cost of wind energy. We see great potential in efficient battery technology, as a step towards a fully sustainable energy supply, says Anders Vedel, CTO and Executive Vice President, Vestas.