We introduce a new non-condensing thermodynamic cycle that uses the chemical adsorption affinity of new nanostructured porous materials in a thermal compressor that eliminates the evaporator, condenser, and high pressure pump in the standard ORC to produce 40% more power from the same temperature heat source and can switch modes to cooling if required. This CCHP system is driven by low-grade heat (T less than 150 oC) and can operate in ambient temperatures over 40 oC. There is great interest in extracting economic benefit from the vast quantity of low and mid-grade heat rejected to the environment from primary energy conversion sources. In the U.S., this amounts to approximately 59 quads of wasted thermal energy. Geothermal resources at temperatures between 100 and 200°C represent an additional very large (100 GWth) and widely geographically dispersed resource. Solar PV panels convert the majority of the incident solar radiation to heat as well. The principal reason why these thermal resources are not more fully exploited is cost. Low grade heat sources have modest exergy that can be turned into useful work. This means that standard power generation equipment, heat exchangers, expanders, pumps, etc. are significantly larger for the amount of power generated and efficiency of standard thermodynamic cycles such as the Rankine cycle are inherently low, less than 10% typically. The resulting high capital and operating costs relative to the amount of revenue that can be generated from power sales is rarely very economically attractive, especially today with low costs for natural gas. Hence there is a pressing need for new concepts that can dramatically bend the cost curve of power production from low grade heat sources. In this presentation, we describe a new non-condensing thermal compression cycle that offers potential for transformational improvements in cost and efficiency as compared with standard ORC systems.

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