Performance Evaluation of Two Similar 100MW Solar PV Plants Located in Environmentally Homogeneous Conditions

With recent steep decrement of Photovoltaic (PV) module prices, many utilities around the world are investing in large scale solar PV power plants to meet their energy needs. Countries with an ample amount of deserted areas tend to utilize it for the purpose of energy generation. This article reviews two equal power rated solar PV power plants with similar environmental conditions located next to each other with similar installed equipment but different output energy generation. Various factors affecting the generation of these technically similar power plants such as PV module tilt angle, inter row spacing, annual degradation effect, the negative temperature coefficient of power and other causes are explored evaluate the performance along with the assessment of reasons for deviation in the performance. The energy output trend and the percentage difference for each month for a complete year are graphed for analysis with and without considering the degradation effect to give a level playing field for both the PV plants under review. The efficient design of tilt angle, inter row spacing for the area of installation with the help of sun charts and shading occurrence diagram, is of utmost importance to maximize the energy yield. Any laxity in designing these parameters result in heavy financial losses to the investor which multiply over the life cycle of the project. Similarly, an improved and proper design can increase the energy output and have a positive impact on the financial savings of the investor which in this case is USD 0.85 million per annum.