NSF Award
1345502
This Small Business Innovation Research (SBIR) Phase I project will investigate an energy storage technique utilizing water as the storage material in an ionic, time delayed, freeze-point-suppression refrigeration cycle. The project will demonstrate A) 70% Round-Trip-Efficiency on a 2kW system prototype utilizing diurnal ambient temperature swing and B) commercial feasibility of load shifting energy storage with < 3-year payback. Successful integration within low temperature refrigeration architectures requires reducing membrane distillation feed temperature and liquid-to-solid thermal regeneration equipment costs, technical obstacles demanding membrane material coatings and advanced additive manufacturing research. More specifically, the project team will advance air-gap membrane technologies by enabling wide temperature module operation via new membrane and condenser surface coatings, while improving liquid-to-solid thermal regeneration utilizing a single, 3D printed heat exchanger designed and optimized for sub-0C applications. <br/><br/>The broader impact/commercial potential of this project provides utilities peak demand relief, retail stores reduced freezer operating costs and regulators safer refrigerants. Unfortunately, no state-of-the-art system simultaneously addresses all these issues. Industrial/commercial energy storage is unaffordable, refrigeration costs account for 60% of a retail store?s electricity bills and equipment manufactures are scrambling to design around toxic ammonia and high pressure, high cost CO2. This energy storage technology provides load-shifting services and a 45% reduction in commercial freezer electrical purchases with a 3-year payback without large government incentives using safer, near ambient, materials.
