Economic analysis on domestic photovoltaic arrays

Partial shading, which directly affects the payback period and efficiency, cannot be avoided completely in domestic integrated photovoltaic (PV) arrays. Up-to-date economic analysis under partially shaded conditions is not reported in detailed in the literature. In this paper a techno-economic analysis was carried out to demonstrate how the selection of a PV module effects the power extraction and economics under partial shading. Due to the cost effectiveness bypass diodes were selected as the mitigation technique for partial shading. Shading effects were modelled using Quite Universal Circuit Simulator (QUCS) software, by connecting five modules (each having 60 cells and same power rating) readily available in the market in series and evaluating the costs and payback periods per kW. The P-V curves of the modelled PV modules were used to get the maximum power that can be extracted under shaded conditions. Results showed that the payback period was at a minimum when 240 W PV modules were used as the building blocks. The procedure developed in this paper will help a practitioner to select a specific PV module in the market to suit for a given shading pattern.