Tuesday, March 19, 2013

Redox flow batteries can solve solar energy intermittency?

Solar energy has almost unlimited potential because our Sun is by far the biggest source of renewable energy on our planet. However, there are several major challenges towards the global solar energy domination with one of the most demanding being the intermittency issue.

In order to counter intermittency of solar energy we need powerful electric energy storage devices that would be able to fix the resulting irregularities in the power supply.

Many scientific researches, from all over the world, are aimed at developing new, more cost-effective energy storage solutions. One of the latest interesting studies comes from the Fraunhofer scientists who have developed redox flow battery that reaches stack power up to 25 kW, with a cell size of 0.5 square meters. This is eight times larger than the previous A4-sized systems.

The researchers have explained that redox flow batteries offer an effective way to balance out fluctuations in the supply of solar (as well as wind) energy and thus guarantee its constant availability. The working principle of these batteries is as follows: „Batteries store electrical energy in chemical compounds, the liquid electrolytes. The electrolytes are charged and discharged in small reaction chambers.“

The batteries that are currently available on the market, roughly the size of A4 paper (can only generate 2.3 kilowatts (kW) of power and to increase the size and capacity researchers had to use brand new design that has allowed them to produce stacks up to 0.5 square meters in size.

Redox flow batteries offer several advantages; they are cost-effective, robust, durable, and can be individually customized. This new battery will be presented to public at the Hannover Messe trade show (from April 8-12).