This Small Business Innovation Research (SBIR) Phase I project will develop critical measurements necessary for eventually producing a high efficiency Thermal Engine with Metastable Power Extraction Step (TEMPES). The TEMPES thermodynamic power cycle is designed primarily for low-temperature power generation and waste heat recovery. The basic operating principle of the TEMPES engine is a closed 2-cycle cylinder piston assembly that converts heat energy in a working fluid to mechanical energy using an innovative thermodynamic power cycle. The method of conversion from heat energy to work is accomplished via formation of metastable non-equilibrium states in a portion of the thermodynamic cycle. Unlike states that are thermodynamically equilibrated, metastable states incorporate a temporal component and history required for fixing the state. Metastable state formation and state trajectories have been previously demonstrated in our lab providing a means for conducting a preliminary analysis of a theoretical TEMPES power cycle. The awarded research work will expand this knowledge base by producing an experimental set-up more closely tailored to closed cycle configurations for ultimate power generation. This experimental configuration will allow detailed characterizations of metastable states and the mechanisms by which these states form and collapse back into equilibrated thermodynamics states.
The broader impact/commercial potential of this project is related to the vast supply of low grade waste heat that could be converted into useful energy. The TEMPES technology can be the core of a scalable electricity generation system using low-grade waste heat as its primary energy source. Recovery of low-grade waste heat can potentially reclaim trillions of BTUs annually from industrial waste heat sources, concentrating solar plants, geothermal plants, and waste-water treatment facilities and convert this energy back into useful work. Low temperature power conversion technology at temperatures <350 C is enabling for waste heat recovery power generation, solar trough power generation, and geothermal power generation at both consumer level and large grid scale energy applications.