Comparative Performance Analysis of Photovoltaic Power Plants – a Case Study

Abstract

The aim of this paper is the comparative study of the behavior and performances of two photovoltaic power plants of different installed power, but which uses identical equipment. The difference in size is being given by the number of specific equipment used (the power inverters and solar panels). The plant behavior was investigated, as the injected active power is dependent on the available sunlight to the photovoltaic panels (and a larger plant leads to a larger panel area), as well as the influence of the power plants to the power grid, given the fact that a large power plant will inject more active power, and the grid local power transformer must be able to accept this power. The power plants efficiency was also investigated, as typically, the bigger the plant, the higher the efficiency must be. But, the efficiency depends on the generated active power (which must be high, to have a good efficiency) and in the case of photovoltaic power plants, the produced power depends on the available sunlight, and again, the bigger the plant, the bigger the panel area susceptible to be shaded. This gives the fact that although the injected power is higher for the bigger power plant, if the power of each inverter is below the rated power, the overall efficiency is lower compared to the small power plant which works at the rated power.