Storage of thermal energy at high temperature.

The Danes are experimenting with stones for the storage of thermal energy at high temperature, a way to boost renewable energies in the country. Rocks are cheap and respectful materials with the environment.  Renewable energy produces excess energy at certain times that can be used to pump very hot air to a group of stones, where energy can be stored for several days with little loss.

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The process can be reversed by forcing the hot air out of the storage, which in turn creates steam from the water to drive turbines that generate electricity and thus produce hot water for district heating. 

In preliminary studies they are trying to find the right stones and the energy storage model. So far they have applied the bowl shape.  According to the Danish Energy Agency and Storasol, the technical data related to the project for 2016 can be summarized as follows

Denmark already has a very complete district heating system, the relative loss in the generation of electricity from heat has less impact.  This fact helps guarantee a high level of use of stored energy, even when the price of storage in batteries of chemical products is increasingly competitive. 

More information: energilager.nu - storasol.eu