Extended exergy analysis of a photovoltaic-thermal (PVT) module based desiccant air cooling system for buildings

In this paper, a photovoltaic-thermal (PVT) module based desiccant air-cooling system for buildings is analyzed by extended exergy analysis. Extended exergy analysis contains all information about material, energy, capital, labor, and environmental flows. The results show that the extended exergy analysis gives different results from conventional exergy analysis in terms of exergy destruction and exergy efficiency. The maximum exergy efficiencies of the system are 0.84 and 0.18 by considering the conventional and extended exergy analyses, respectively. Another important change is shown in the exergy destruction owing to the increase from 5085.50 kJ to 98029.50 kJ in maximum values for conventional and extended exergy analyses, respectively. When extended exergy items are taken into account, it is seen that exergy equivalent of the capital has the biggest portion. This is mostly resulted from the great expenses of the electricity consumption. That's why, either electricity consumption needs to be decreases by using efficient systems or electricity should be generated via renewable energy. These methods would be useful to increase in exergy efficiency and decrease in exergy destruction.