New energy storage technology will give old fossil power plants a new future as green batteries. The springboard is a new joint European project in Bornholm, Denmark, which aims to show that long-term storage of wind and solar energy is possible on a large scale.
In the “2nd Life to Power Plants” (2LIPP) project, supported by a DKK 60m grant from the EU and with a total budget of DKK 100m, partners from six European countries will join forces to transform the obsolete plants of the past into green batteries. In the Bornholm project, a fossil power plant is to be converted into a battery that stores surplus green electrons and sends them back into the electricity grid when the green energy sources from wind and sun fall short. The purpose is to present a scalable, hybrid energy storage solution consisting of three technologies combined in a new energy management system to utilise existing plant infrastructure to achieve lower establishment costs for fossil-free plants.
On Bornholm, they will be building an energy storage solution using liquid sodium hydroxide, commonly known as lye or caustic soda, where they will store green energy as heat and return it to the electricity grid when needed. The advantages of using hydroxide salts for combined heat and electricity production are: very low material price, high energy density, high temperatures up to 700 degrees, and that energy can be stored for up to two weeks.
In addition to energy storage in salt, the hybrid storage consists of used car batteries from PLS Energy Systems and a high-tech flywheel from QuinteQ that stores energy in short intervals. All three storage technologies are tied together by an energy management system from Pini Solutions that utilises the entire store of energy to balance the power grid and provide district heating and power when needed.