Led by Munich Re Ventures, with follow-on investments from DCVC and Breakthrough Energy Ventures, the funding will accelerate the commercial deployment of Fourth Power's modular, utility-scale thermal energy storage system. The funding will support commissioning of an integrated 1 MWh-e demonstration using full-scale commercial components and is the company's final step before customer deployments. Additionally, this capital will be used to deepen partnerships with suppliers and customers further and grow the customer pipeline.

Fourth Power delivers utility-scale energy storage that grows with the grid to meet today's short-duration needs and tomorrow's long-duration requirements. By combining thermal energy storage with thermophotovoltaic (TPV) cells, Fourth Power turns the light emitted from heated carbon blocks into electricity that is dispatchable to the grid in seconds. The company's extremely high-temperature system (2400°C) ensures maximum power density with abundant domestic materials, delivering energy storage at less than $25/kWh-e-ten times cheaper than lithium-ion batteries. Fourth Power's modular system provides flexible duration from 5 to 100+ hours, allowing utilities to start small and scale seamlessly as grid conditions evolve.