Changing The Policy of Fixed Orientation of PV Modules from Maximum Radiation to Maximum Saved CO2 Emissions of Thermal Power Plants

Document Type : Original Article


1 University of Shahid Beheshti, Tehran, Iran

2 Tehran, University of Shahid Beheshti

3 Tehran, Iran Grid Management Company



Generally, optimal fixed orientation of PV modules is supposed to be the one that receives maximum solar energy. To receive maximum energy, tilt angle is typically set on the latitude angle of the installation site and the module orients toward the south axis of earth. In other words, it is assumed that if the module orients toward the maximum point of solar energy absorption, maximum electrical energy is generated and maximum fossil fuel pollutants emitted from one sample thermal power plant to generate the equivalent electricity is saved. PV system orientation angle accuracy has the potential to avoid tonnes of GHG emissions without any investment, operation and maintenance costs. If the module is not placed in the proper orientation, the emitted pollutants of the sample plant would not be maximum. In this research, fuel type and efficiency of sample plants are considered as the prime factors in determining the optimal orientation.  The paper aims to show that the proper orientation for maximizing saved CO2 emissions of thermal power plants is not equal to the orientation of maximum radiation and the related tilt and azimuth angles are different.


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