Comparative Performance Assessment of a Hybrid Solar-Coal Power Plant

Abstract

The focus of present study is to investigate technical, environmental and economic aspects of integrating concentrated solar energy into an existing 210-MW coal-based power plant for feed water heating. A possible alternative for such systems is a hybrid system (an integration of concentrating solar power (CSP) technology and fossil fuel based power plants), referred as solar thermal hybrid technology (STHT). The present investigation proposes integration of existing coal-fired power plant with concentrated solar energy. In this study, the steam extracted from first stage of turbine is replaced by solar energy; thereby reducing amount of heat input from the boiler considerably. This hybridization of existing coal-fired power plant with solar energy reduces coal consumption and CO2 emissions in fuel saving mode. The power output of hybrid solar-coal plant is augmented in power boosting mode when first-stage extraction steam replaced by solar energy is allowed to expand further in Rankine cycle. This study also compares the performance of hybrid solar-coal power plant in fuel saving and power boosting mode. An algorithm based upon this STHT plant is developed in MATLAB. Based upon this algorithm useful heat input and thermal losses that occur in the tubes of the solar collector have also been discussed in this paper.