Feasibility Study of Heat Driven Cooling Based Thermal Energy Storage

Human needs are unlimited, but resources are limited to satisfy these needs. Because of this reason, consideration of sustainability in utilization of energy is of immense importance. As an intelligent species, mankind is interested in satisfying their needs sustainably. In this view, use of renewable energy, reduction of energy usage, and reduction/ elimination of use of fossil fuels are of great importance. It can be observed that there is rising demand for space cooling, and it has the highest share of energy consumption in the building sector. Colombo, Sri Lanka has a hot and humid climate, and above mentioned condition prominently prevails. On the other hand Sri Lanka experiences a considerable increase of energy demand and electricity tariff rates annually and this trend is prominent. Therefore the demand for finding energy efficient, renewable and cost effective solution is ever increasing. Accordingly, this study was carried out to conduct a techno-economic feasibility on thermal energy storage integrated into absorption chiller. Both these technologies are commercially available and have the measure towards sustainability. It was observed that most common air conditioning applications are in office buildings, and therefore the focus of this study is on a typical office building in Colombo city. The result of the study can be then applied to other office buildings in the city. Trace700 software tool was used to model and simulate the different system alternatives and to investigate the energy and economic performance. It was found that the cool thermal storage integrated into thermally driven absorption chiller has a good energy saving and cost saving potential and biogas can be a better energy source to supply the thermal energy required by the chiller and this energy is utilized in a sustainable manner