Case Studies of Energy Saving and CO₂ Reduction by Cogeneration and Heat Pump Systems

Satoru Okamoto

Department of Mathematics and Computer Science, Shimane University, Matsue, Japan.

DOI: 10.4236/ojee.2013.22014                

Abstract

This paper describes two case studies: 1) a cogeneration system of a hospital and 2) a heat pump system installed in an aquarium that uses seawater for latent heat storage. The cogeneration system is an autonomous system that combines the generation of electrical, heating, and cooling energies in a hospital. Cogeneration systems can provide simultaneous heating and cooling. No technical obstacles were identified for implementing the cogeneration system. The average ratio between electric and thermal loads in the hospital was suitable for the cogeneration system operation. An analysis performed for a non-optimized cogeneration system predicted large potential for energy savings and CO₂ reduction. The heat pump system using a low-temperature unutilized heat source is introduced on a heat source load responsive heat pump system, which combines a load variation responsive heat pump utilizing seawater with a latent heat-storage system (ice and water slurry), using nighttime electric power to level the electric power load. The experimental coefficient of performance (COP) of the proposed heat exchanger from the heat pump system, assisted by using seawater as latent heat storage for cooling, is discussed in detail.

Keywords

Cogeneration System; Heat Pump System; Energy Saving; CO₂ Reduction; Hospital; Aquarium

Conflicts of Interest

The authors declare no conflicts of interest.

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