In response to the increasing demand for renewable energy integration into the grid, Fourth Power has secured $19 million in Series A funding to expand its groundbreaking thermal battery technology. Led by venture capital firm DCVC, the investment round includes participation from Breakthrough Energy Ventures (BEV) and Black Venture Capital Consortium. The funds will not only support the scaling of Fourth Power’s cost-effective thermal energy storage solution, capable of storing energy for various durations but will also kickstart the construction of a 1 MWh-e prototype facility near Boston, with an expected completion date in 2026.
Without efficient energy storage, the reliance on fossil fuels persists as renewable sources like wind and solar must be used immediately upon generation. Fourth Power’s technology addresses this challenge by utilizing renewable energy to heat carbon blocks to extreme temperatures, subsequently releasing the stored heat as electricity when needed.
The system transforms renewable energy into thermal energy, storing it until required. The thermal battery heats liquid tin, circulating it through a piping system to heat stacks of carbon blocks until they emit intense heat. The thermophotovoltaic (TPV) cells are then exposed to this light, converting it into electricity. This innovative solution is designed to optimize the value of renewable energy generation, providing grid operators with cost-effective control and flexibility. Additionally, the modular and scalable nature of the system allows for the addition of more carbon blocks to extend storage duration, accommodating the growth of renewable energy generation.
Fourth Power’s utility-scale energy storage approach anticipates the growth of wind and solar energy generation. By effectively storing renewable energy that would otherwise be wasted during curtailment, the system enables storage for over a month and allows discharge over variable periods, from a few hours to a few days, all at a minimal cost. This flexibility, including the ability to discharge within seconds, is crucial for grid operators striving to ensure a reliable 24/7 power supply.
Conceived by Dr. Asegun Henry during his tenure at Georgia Tech and now associated with MIT, Fourth Power’s thermal battery technology boasts several records, including a 41% thermophotovoltaic efficiency and the Guinness World Record for the highest temperature pump. Beyond the establishment of the 1 MWh-e facility, the funding will support rigorous durability testing and the expansion of the company’s engineering team to meet the escalating demands of the market.