2Centre for Energy Studies, Indian Institute of Technology (IIT) Delhi, Hauz Khas- 110016, New Delhi, India
Abstract
The increasing energy costs and environmental awareness call for a shift towards some interesting energy alternatives preferably the use of renewable energy. The present study investigates the impact of varying cooling capacity and other operating parameters in a single-effect absorption refrigeration system, using the concept of energy and exergy as a building heating/cooling alternative. The solar heat is used as an input to the generator of absorption refrigeration system. The results obtained from investigation revealed that variation in cooling capacity influences coefficient of performance (COP), exergy loss in different components as well as exergy efficiency. The values of COPcooling and COPheating lies in the range of 0.71-0.89 and 1.71-1.89 respectively for variations in cooling capacities ranging from 1 TR to 20 TR at maximum generator temperature of 80oC. However, exergy efficiency of the system lies in the range of 0.32-0.41 for same variation in cooling capacities. It has also been established that an increase in evaporator temperature and at maximum cooling capacity both COPcooling and COPheating shows an increasing trend. The exergy efficiency also shows maximum value at the highest cooling capacity at a particular evaporator temperature which further with an increase in evaporator temperature shows a decreasing trend. The irreversibility behavior in all the components i.e., solution heat exchanger, absorber, generator, evaporator and condenser shows an expected trend with the variation in cooling capacity. Hence, use of the above mentioned system as a heating and/or cooling alternative for buildings is suggested.