InteliSpark client, Active Energy Systems, Inc. has been awarded a Phase I SBIR grant from the National Science Foundation (NSF) for their project, “Grid-scale electricity storage from waste heat”. This project will focus on significantly lowering the cost and expanding the number of addressable markets for ice thermal energy storage.
Cost effectively storing energy is imperative to a sustainable future. Storage can provide reliable access to power from intermittent renewable sources, increase the resiliency of grid to weather events or terrorist attacks, and increase the utilization efficiency of existing assets, deferring costly upgrades. Today, ice thermal storage systems help building owners shift cooling loads from costly peak hours to when electricity is less expensive. Unfortunately, the upfront cost of these systems, driven by the large cost of the cooling coil used to generate ice, prevents adoption from many users and has unduly restricted the number of addressable markets for ice thermal storage. Elimination of ice buildup on the cooling coil would reduce the size of the coil, and more importantly significantly lower the cost of these systems.
Low-cost ice thermal energy storage could greatly improve the economics for long-duration energy storage technologies such as pumped thermal energy storage. Active Energy Systems will use the grant funding to translate the discovery of surfaces with zero ice adhesion into a cooling coil that can be integrated into a functioning ice thermal energy storage system. They plan to systematically prototype and refine various plate and tube-based cooling coil geometries, measuring the freezing and melting heat transfer efficiencies. They will also test different formulations of the surface coating. The most promising candidate geometries will be charged and discharged over multiple cycles as a part of an ice thermal energy storage system. The results from cycling will be compared to conventional ice-on-coil technology using metrics such as energy density and heat transfer efficiency. An ice shedding cooling coil, at less than a third of the size of an ice-on-coil system, is expected to deliver improved cooling performance. Demonstration of an ice shedding cooling coil in a functioning ice thermal energy storage system will prove the technology’s readiness to scale.