Modern-day Energy Storage Systems
Energy storage systems are one of the key technologies for the energy turnaround. With their help, the fluctuating supply of electricity based on photovoltaics and wind power can be stored until the time of consumption. At Karlsruhe Institute of Technology (KIT), several pilot plants of solar cells, small wind power plants, lithium-ion batteries, and power electronics are under construction to demonstrate how load peaks in the grid can be balanced and what regenerative power supply by an isolated network may look like in the future.
“High-performance batteries on the basis of lithium ions can already be applied reasonably in the grid today,” says Dr. Andreas Gutsch, coordinator of the Competence E project. As stationary storage systems, they can store solar or wind power until it is retrieved by the grid. “When applied correctly, batteries can also balance higher load and production peaks and, hence, make sense from an economic point of view.”
The Competence E project is presently developing several pilot systems consisting of photovoltaics and wind power plants coupled to a lithium-ion battery. Over a development phase of two years, a worldwide battery screening was made. “Now, we know which lithium-ion cells are suited best for stationary storage systems,” says Gutsch. The first stage of the modular systems will be constructed on KIT Campus North by the end of 2012. It will have a capacity of 50 kW.
A newly developed, gear-free wind generator that is particularly suited for weak wind regions will complement electricity production by the photovoltaics system in the winter months in particular. The first stage will be able to cover electricity consumption of a medium-sized company throughout the year. In the long term, the know-how obtained will be used to develop smaller storage systems for private households as well as larger systems for industry.