• Bill Gates’ energy innovation fund has backed Fourth Power, a Boston-based startup developing a novel liquid tin energy storage technology.
• The startup has secured $19 million in Series A funding, intending to further develop its thermal battery technology and establish a 1 MWh-e prototype facility near Boston.
The funding initiative from Bill Gates’ energy innovation endeavor is focused on Fourth Power’s ground-breaking battery technology which uses liquid tin for energy storage. This technology holds a Guinness World Record for energy storage at incredibly high temperatures. Fourth Power has been granted $19 million in Series A funding with the intent of scaling its revolutionary thermal battery technology. The investment round was led by DCVC and also featured contributions from Gates’ Breakthrough Energy Venture and the Black Venture Capital Consortium.
The funds will also facilitate the creation of a 1 MWh-e prototype facility near Boston, expected to be operational by 2026. The technology, which was conceived by Asegun Henry, Ph.D., during his time at Georgia Tech, already holds several accolades, most notably the Guinness World Record for the highest temperature pumping of liquid metal at 12,000 degrees Celsius.
Fourth Power aims to reduce reliance on fossil fuels in line with global efforts to transition away from these traditional energy sources. The core belief driving this initiative is using renewable energy, such as wind and solar, immediately upon generation, negating the need for energy storage.
The company’s technology utilizes renewable energy to heat carbon blocks to temperatures resembling the sun. The stored heat can then be released on-demand to supply a reliable source of electricity. With ambitions to deploy this solution at a global scale, the development of scalable, utility-scale energy storage solutions that can grow along with expanding grid infrastructures is critical.
The thermal battery technology developed by Fourth Power converts renewable energy into thermal energy, stored for future use. It employs liquid tin to generate heat—this is circulated through a network of pipes to heat carbon blocks until they radiate intense heat. The system then uses thermophotovoltaic (TPV) cells, exposed to the glowing carbon blocks, to convert the stored thermal energy into electricity.
Not only does Fourth Power’s solution efficiently store renewable energy that might otherwise be wasted through curtailment, but it also provides valuable flexibility for grid operators aiming to maintain a reliable power grid. The solution is highly scalable and modular, allowing for increased storage duration by simply incorporating additional carbon blocks. The funded prototype facility will also support comprehensive durability testing and allow for the expansion of the company’s engineering team, ready to address rising market demands.