The Enel Group and Brenmiller Energy are developing a sustainable energy storage system that uses rocks to store thermal energy.
The thermal energy storage system can be used to store excess energy produced from renewable sources in the form of heat to offer decarbonisation services to industrial customers and to integrate long-term storage solutions with renewable plants.
It utilises a two-stage charge and discharge process to provide thermal energy. During the charging phase, steam produced by the Santa Barbara facility passes through pipes to heat adjacent crushed rocks; during the discharging phase, the accumulated heat is released to heat pressurized water and generate steam for electricity.
This first-of-its-kind TES system can store up to 24MWh of clean heat at a temperature of about 550°C for five hours, providing critical resiliency to the power plant.
The partners inaugurated the project at the Santa Barbara power plant in Tuscany, in the municipality of Cavriglia
By integrating it with the existing power plant, Enel and Brenmiller can test the technology in the field, in challenging operating conditions and on a large scale.
The system offers reduced power plant start-up times and greater speed in load variations, which are necessary performance requirements to enable the efficient use of renewable energy.
“Flexibility and adequacy are two fundamental components of an efficient and reliable electricity system, which can be supplied more and more efficiently by storage,” said Salvatore Bernabei, Head of Enel Green Power and Thermal Generation at Enel.
“This trial allows us to validate a family of innovative and sustainable technologies in the segment of long-term storage, which will allow for an ever greater integration of renewables into the grid.”