Life Cycle Cost Analysis and Carbon Credit Earned by Hybrid PV/T Solar Water Heater for Delhi Climatic Conditions

In this communication, a study has been carried out to evaluate the life cycle cost analysis and carbon credit earned by hybrid PV/T solar water heater. The study has been based on thermal, electrical and exergy output of water heater. The solar water heater is installed at Solar Energy Park, IIT Delhi. The annual energy and exergy gain have been evaluated by considering four types of weather conditions (A, B, C and D Type) of New Delhi and considering a case that the hot water is withdrawal two times in the afternoon and two times in the evening in a day. This paper gives the total carbon credit earned by hybrid PV/T water heater as per norms of Kyoto Protocol for Delhi climatic conditions. We have found that (i) the cost/kWh is higher in case of exergy when compared with cost/kWh on the basis of thermal energy (ii) if this type of system is installed at 10% of the total residential houses in Delhi then the total carbon credit earned by PV/T water heater annually in terms of thermal energy is Rs. 105.6 cores and in terms of exergy is Rs. 10.2 cores respectively. The thermal energy has wider applications in the hu- man's life. It can be generally utilized in the form of either low grade (low temperature) or high grade (high tempera- ture). The temperature profiles of the photovoltaic (PV) module in a non-steady state condition with respect to time have studied (1). The overall electrical efficiency of the PV module can be increased by increasing the packing factor (PF) and reducing the temperature of the PV module by us- ing the thermal energy associated with the PV module (2, 3). The carrier of thermal energy associated with the PV module may be either air or water. Once thermal energy withdrawal is integrated with the photovoltaic (PV) module, it is referred as hybrid PV/T system. Photovoltaic-thermal (PV/T) technology refers to the integration of a PV module and conventional solar thermal collector in a single piece of equipment. The rationale behind the hybrid concept is that a solar cell converts solar radiation to electrical energy with peak efficiency in the range of 9- 12%, depending on specific solar-cell type and thermal en- ergy through water heating. More than 80% of the solar ra- diation falling on photovoltaic (PV) cells is not converted to electricity, but either reflected or converted to thermal en- ergy. In view of this, hybrid photovoltaic and thermal (PV/T) collectors are introduced to simultaneously generate electric- ity and thermal power (4). The PV/T water heating system, two types of combi-