Renewable Flow Storage

Flow battery

ready for home use

The main objective of Renewable FlowStorage (RFS) is to develop and field-test a vanadium redox flow battery (VRFB) for storing electricity for domestic residential with PVs. It targets the development of a full prototype machine of 1 kW and 4 kWh storage capacity. VRFBs are very robust, flexible, environmentally safe and seen as the lowest price local stationary electricity storage technology that fits the needs of the private residential market. A VRFB is a reversible fuel cell where the redox pairs are dissolved in an aqueous phase and stored in separate tanks. One of the very attractive features of redox flow batteries are scalability between storage capacity and battery power. 

Electricity storage needs will burst dramatically in the coming years, and is driven by: i) nearly zero energy buildings (NZEB) EU directive that becomes enforced for private users already in 2021; ii) the high grid price of electricity in Denmark but also in Germany, Spain, Italy and Portugal; iii) the change in policy of several EU countries concerning feed-in tariffs that are considerable lower than buying from the utility grid; iv) the need to stabilize the low voltage grid.

The main objective of RFS is to develop a VRFB prototype with an attractive casing and user interface for domestic use. The first complete prototype will be ready for field-tests no later than 20 months after the beginning of the project. It will be used in field-tests to assess both the economic and technical feasibility of VRFBs for domestic storage of PV electricity and to assess the potential for load levelling of the local low voltage utility grids. The goal at the end of project is to have a design and balance-of-plant ready to be implemented in the first 0-series ready for sales.


PHOTO TOP: A new type of flow battery can store electricity cheaply, safely and efficiently. Visblue is a spin-out company that expects to have a commercial product available for consumers within a year. Pictured here is Anders Bentien, one of the researchers behind the new invention. (Photo: Anders Trærup)