Energy storage can help balance variable renewable generation, but “storage” covers technologies designed for different jobs. Israeli examples include hot-rock thermal storage for industrial heat, ice storage for shifting building cooling demand, and aluminum-air systems intended for long-duration backup. Their capacities cannot be compared directly without considering whether the output is electricity, heat or cooling.The Israel Ministry of Energy’s research and development report also describes Brenmiller’s earlier pilot work; see its 2020–2022 R&D report.
Thermal storage supplies heat on demand
Brenmiller Energy’s bGen technology stores heat in crushed rock and later uses it to produce steam or hot air for industrial processes. This can shift when electricity is consumed: the storage can charge when power is available and provide heat when a factory needs it. A German Aerospace Center handbook describes a 32 MWh thermal storage system planned for Tempo Beverages in Netanya, with construction beginning in 2025 and commissioning expected in 2026. At the handbook’s publication, the system remained in construction or commissioning, and full performance at scale had not yet been proven. See the DLR thermal storage handbook.
Ice storage takes another route: it makes ice when electricity demand or prices are lower, then uses melting ice to provide cooling later. This shifts cooling loads rather than supplying general electricity to the grid. The value depends on building demand, equipment and local tariff structure.
Metal-air systems use replaceable fuel
Phinergy develops aluminum-air energy systems. Oxygen from ambient air reacts at an aluminum anode in a water-based electrolyte to generate electricity; the aluminum is consumed and must be replaced, so the system is mechanically recharged rather than recharged like a lithium-ion battery. The company describes this as suited to backup and marine applications, and explains the reaction and recharge method on its technology page.
Metal-air’s high energy density can be useful where long duration and weight matter, but the spent material must be collected and recycled, and the aluminum supply chain has its own energy and environmental footprint. It is not a drop-in substitute for batteries designed for frequent electrical cycling.
These examples show Israeli innovation at different stages and for different markets. For hydrogen as another way to store renewable energy, see H2Pro’s E-TAC process.