The Enel Group and Brenmiller Energy have started a sustainable energy storage system in Santa Barbara, Tuscany.
The goal of the thermal energy storage (TES) project is to build a thermal storage system in Santa Barbara which is completely sustainable. The integration of the TES system with the existing power plant enables Enel and Brenmiller to 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. The system can be used to store excess energy produced from renewable sources in the form of heat to offer decarbonization services to industrial customers and to integrate long-term storage solutions with renewable plants.
The TES technology utilizes 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 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 companies say.
Enel has already opened a thermal energy plant with EnergyNest. In 2018, the company’s thermal energy storage technology, when integrated in full-scale, provides annual CO2 reduction of up to 45,000 tons, 14 million liters of fuel oil saved per year, and project payback in less than three years.
The collaboration launched with EnergyNest gave Enel the chance to evaluate EnergyNest’s thermal energy battery solution in real-life conditions and identify full-scale business applications for the technology integrated into thermal power plants. The objective of the project demonstrated how waste heat recovery in thermal energy storage can increase flexibility and sustainability of thermal power plants.
