PL
The analysis, which has been conducted for four households in France, has shown that the use of photovoltaic panels for electric energy production has been economically effective. The analysis has been conducted using RETScreen® International software and compared with real data form system owners. The calculations were based on daily solar radiation and have been demonstrated using a simple payback period and internal rate of return. The majority of the photovoltaic system’s necessary cost has been taken into account. The calculations have demonstrated that a simple payback time for systems set before 2012 is below 10 years, which is a half time of panels’ life span. Moreover, the ecological effect on producing electric energy using analyzed systems has been calculated.