Resorting to appropriate specifications for the required utilities and then optimally designing systems to cater to the requirement of various cold and hot utilities will help in addressing sustainability. Energy cost reduction has become essential in order to compete in the global market. One way to achieve significant energy cost reduction, in HVAC&R applications, is by recovering and recycling waste heat.

Co-generating cold and hot utilities will reduce energy consumption and associated cost. Recovering heat from existing air conditioning and refrigeration systems, and using it to meet the demand for hot water, drying, dehumidifying, etc., in various commercial as well as industrial applications can prove to be very attractive. Heat pump is also a device which can be used to deliver cold and hot utilities (Seo, (2000), Rane and Gupta (2001), Rakhesh etal. (2003), Lam and Chan (2003)). Patented Multi-Utility Heat Pumps (MU-HP) can simultaneously cater to cooling and heating requirements while reducing the input energy, Rane and Das Gupta (2003). Proper application engineering is a key to reducing energy usage and associated cost.

Paying attention to component efficiencies (Szargut, 2002) and developing suitable delivery mechanisms like radiant heating and cooling panels (Kilkis, 2006) will help improve overall system efficiency further. MU-HP is a device which pumps heat from, one or more low temperature source/s to one or more high temperature sink/s simultaneously, with the help of an external source of energy. MU_HPs can be of various types, viz. vapour compression, thermoelectric, absorption, adsorption and ejector.