Bounding Limitations in the Practical Design of Adsorption Heat Pump Water Heaters

The boundary temperatures for any sorption-based technology can be estimated on the basis of Trouton's hypothesis that isosteres, extrapolated to infinite pressure (or analogously to infinite temperature) meet at a single point. In this paper we discuss the consequences of this hypothesis for many sorption devices that are thermally operated, suitable for exploiting renewable energy resources, or making better use of high or low level thermal energy. Trouton's hypothesis is independent of the working fluids making it particularly useful to both liquid-vapor and solid-vapor systems. We exemplify the use of the derived boundary temperatures derived from Trouton's hypothesis to important processes such as ice making, space cooling in hot climates, deep freezing, and residential hot water production. The boundary temperatures help determine which sorption or solar heating technology may be better suited to serve the given application, or whether it is beyond the scope of sorption systems.