Optimize on the temperature of solar collectors in solar aided coal-fired electric generation

Utilizing multi energy sources synthetically and efficiently based on the system integration is one of the trends of energy science recently. In this study, from the view of the second law of the thermodynamics, we calculate the exergy efficiency of the LS-2-parabolic trough collector, get the exergy efficiency curve in various outlet temperatures and acquire the optimal operating temperature of the collector. Base on the above conclusion, solar aided coal-fired electric generation systems are proposed. The mature parabolic trough collectors were used to collect solar heat and integrated into the regenerative feed-water heaters of different capacity coal-fired plants. We conclude that the coal conservation effect of using solar energy to instead of the feed-water heaters´ higher part in smaller capacity units is better than other units.