IMPROVED TECHNIQUE TO EVALUATE PERFORMANCE OF SOLAR THERMAL POWER PLANT

Abstract

Energy is essential component of socio-economic development and economic growth. The production and assumption of energy is often linked to other major issues in society including poverty alleviation, environment degradation and security concerns. Energy is available in two forms, (solar, wind, small hydro etc) called renewable source of energy and (coal, petroleum, natural gas etc) called non renewable source of energy. In recent years solar energy has received a great attention as an easily utilizable source of renewable energy for providing electricity. Renewable energy like solar is indigenous and can help in reducing the dependency on fossil fuels. The solar energy can be utilized in two ways one is solar photovoltaic and other is solar thermal. In India solar thermal system is used generally for low temperature application i.e. solar water heating, cooking, air heating and drying, cooling and air-conditioning, water purification etc. Hence a limited work has been performed on solar thermal power generation. So performance evaluation of solar thermal power plant is necessary. Performance of solar thermal power plant is calculated by, Deterministic Approach (assigning single input value for a given output value) and Probabilistic Approach (input value is distributive that means every value is given in its all possible range and then corresponding to it we obtain the output). Till now most of the work has been done on Deterministic Approach to study the effect of environmental temperature, varying radiation value, characteristics of collectors and receiver material, circulating fluid etc. Under this dissertation work an attempt is made to evaluate the performance of solar thermal power plant (STPP) considering the effect of thermal inertia (i.e. Time taken by the fluid to achieve minimum temperature necessary to produce electricity) and the effect of wind speed on the performance of solar thermal power plant. Wind speed is responsible for convection losses in receiver, as wind speed increases Nusselt number increases which is directly related to convection loss. The efficiency of each components and then total efficiency of the system have been evaluated by simulating the result using System Analyzer Modeling (SAM) software developed by NREL Laboratory, USA. Based on the performance analysis about 0.53% of efficiency loss is found due to wind speed. However an overall efficiency of the plant is found to be 16.6%.