The growing need for power has necessitated the introduction of innovative solutions for storing the solar and wind generated power during night or low wind conditions respectively.
Energy experts have suggested for the installation of large-sized immobile storage facilities at the vantage centralized locations close to the grid power facilities for holding electric power in megawatt level to meet the power demands during low-level current periods.
A number of researchers from the three Fraunhofer Institutes are presently engaged in developing fluid batteries also known as Redox flow batteries. They aim to construct a battery the size of a handball court with a generation capability of 20 MWh to meet the power requirements of around 2,000 houses during a cloudy day or a long winter night. Though the results are yet to move to an advanced level, the researchers from Fraunhofer Institute for Environmental, Safety and Energy Technology, UMSICHT have produced a battery that produces a few kW level of output. The researchers who participated in the joint development will showcase the functions of a redox flow battery by deploying a 2kW storage plant at Hannover Messe from April 4 to 8, 2011.
Redox flow batteries are actually large-sized batteries that can hold vanadium-based liquids and the element vanadium bonds with the membranes instead of picking up and emitting electrons. Also the use of a single fluid such as vanadium instead of two dissimilar fluids, as available in other type of systems obviates impurities. The small sized reaction chambers where vanadium charges and discharges, are aligned in stacks to improve the installation output of the battery. In order to ensure the smooth flow of vanadium fluid through large sized membranes, researchers have incorporated the flow simulations to better the cell design.
The consortium of Fraunhofer researchers have been developing membranes from materials and formulating battery designs in a collaboration project that received finance from the German Federal Ministry for environment. The Fraunhofer redox flow lab has the capability to build a plant up to 80 kW and a 20 kW power plant is anticipated to go on stream next year. The researchers are optimistic about achieving more than 1MW of power in a period of five years.