SustainX

About SustainX

SustainX emerged from the Thayer School of Engineering at Dartmouth College, established in 2007 by a team that included Ben Bollinger, Dax Kepshire, and Professor Charles Hutchinson. The venture was built upon foundational research into isothermal compressed air energy storage (ICAES), a concept developed to address the intermittency of renewable energy sources. The founders' collective expertise in engineering and energy systems propelled the company's early development.

The company's core offering is its proprietary ICAES™ technology, an energy storage system designed to be deployed virtually anywhere without geographical constraints like underground caverns. This system captures and stores electricity as compressed air. A key aspect of the technology is the process of managing the heat generated during compression. Instead of wasting this thermal energy, the ICAES™ system captures and stores it in water. During the energy release phase, this stored heat is reintroduced to the expanding air, significantly improving the round-trip efficiency of the storage cycle. This approach eliminates the need for natural gas combustion, a common requirement in other compressed air energy storage methods, thereby creating a zero-emissions solution.

SustainX's business model focused on developing and commercializing this energy storage solution for grid-scale applications. The primary clients are electric utilities and grid operators who require robust, long-duration energy storage to balance the power grid, integrate renewable energy like wind and solar, and enhance overall grid stability. The system's use of mature industrial components, such as a mechanical drivetrain based on an electric machine and crankshaft, was intended to ensure a long operational life and a competitive levelized cost of energy (LCOE). Throughout its operational history, the company secured significant funding, including multiple rounds from the U.S. Department of Energy, to build and test its megawatt-scale prototypes. After nearly a decade of development and operations, SustainX was acquired by the Swiss-based industrial conglomerate Sulzer in 2017.