Storenergy, based in Serbia, has developed a thermal energy storage solution (TES) that uses recycled ceramics as a storage medium. It says its solid-state storage solution is designed for long life and low maintenance costs.
Now based in Serbia, Storenergy has developed a modular, packed layer TES solution that uses recycled ceramics as a storage medium. The material was sourced from Masdar City-based Seramic Materials, which obtains recycled ceramics from industrial solid waste such as steel slag, and can store temperatures of up to 1,250C.
“We chose this material because it does not contain complex parts, toxic chemicals or materials,” said Storenergy CEO Marko Vuksanovic. pv magazine.
In Storenergy’s system, the ceramics are heated to 900 C, after which the heat is transferred via air to a heat exchanger and then steam is formed in a classic steam turbine cycle.
“The electric air heater, storage design and steam generator are new parts and everything else is standard equipment, including the steam turbine, condenser and power plant,” said Vuksanovic.
The company has already obtained patents for its technology in the United States, Australia and South Africa, while European documents are in the works.
“We decided to develop our thermal storage solution because of its efficiency and the price it can achieve,” said the CEO.
The fixed asset of the solution is €12 (€13.49)/kWh. In an installation connected to a solar power plant, the levelized cost of electricity (LCOE) is between €42/MWh and €50/MWh for a 1.6 GWh thermal storage system with an electrical output of 10 MW. The levelized cost of heat (LCOH) is €23/MWh for a thermal storage system with an output of 330 MWh and a thermal output of 5 MW.
The energy content of the system per volume is high, 450-500 kWh of heat per cubic meter. “If you compare this to hydropower plants, the difference is huge. A 100-meter-high water column can only store 0.27 kWh/m3. Our system is more compact and has a smaller footprint, and it can be built close to the energy source without location restrictions,” says Vuksanovic.
In terms of heat, Storenergy estimates the efficiency to be around 90%, while in co-production the figure is 60%. In electricity production alone, the company expects an efficiency of around 30-40%.
The system is said to be low-maintenance with a 35-year lifespan. It is designed to store energy for up to a month. “It doesn’t make sense to use it for long periods of time, as the losses are about 1% per day,” says Vuksanovic. According to him, the storage period should be optimally 10 days, when heat loss is 5-10%.
The company’s test project is a 3 MWh TES system that has been commissioned at the CIEMAT Institute in Spain. It is connected to a small Organic Rankine Cycle container turbine and has a footprint of 2m x 2m and is 7m high.
“Now we’re looking for investors who could help us roll out bigger systems,” Vuksanovic said. “We are working on a couple of other projects in Serbia and one abroad. We are also seeing great interest in our technology from India and the Middle East.
Due to the system’s volume and delivery costs, the company’s strategy is to produce most of the construction and manufacturing work close to the project site and in cooperation with local partners at the project implementation sites.
“We want to move our business to the United States, and negotiations are already underway. It’s because it’s the biggest market and always ready for new ideas,” said Vuksanovic.