Using Lime to Store Energy: SOCRATCES

Adam Vincent \ October 28, 2021

The SOCRATCES Project, of which Calix is a member, is commissioning an exciting new application of Calix’s technology at the University of Seville in Spain. Seville is one of the leading locations for concentrated solar power (CSP) research and operation globally.

SOCRATCES is investigating the use of ‘calcium looping’ as a form of concentrated solar power (CSP) energy storage.

In this concept, energy is stored thermochemically by splitting limestone into lime and carbon dioxide in a LEILAC unit, and storing both products separately. This splitting (called calcining) involves large amounts of high[1]temperature energy, and in SOCRATCES’ case this is provided by CSP. The process is reversible, meaning that when electricity is required, the lime and carbon dioxide are recombined in a carbonator to regenerate the limestone and release the stored energy as heat. This heat is converted to electricity using a turbine. This energy storage concept is valuable in locations with high amounts of solar power on the grid; it provides a way to use CSP at night as well as during the day. There is even the opportunity for inter-seasonal storage.

The SOCRATCES project involves the design, construction, operation and integration of a pilot plant to test this concept. It comprises a solar field, a hybrid CSP-electric LEILAC unit from Calix, a carbonator reactor, and a power block. The project is funded by the European Commission through the Horizon 2020 scheme.

Find out more about SOCRATCES

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