The goal of the master thesis is to analyse and evaluate from economical point of view the efficiency of photovoltaic panels during production of electrical, energy and by that to assess the difference in the returns according to the used photovoltaic panels. The tesis consist of theoretical and practical part. Theoretical part includes possibilities of using solar energy, description and characterisation of photovoltaic panels. Furthermore, there has describet legal, economic and technical condicios connected with usage of solar energy within Slovakia.In the prackical part, the analysis of investment projekt evaluates the economic efficiensy of the projekt dependig on the used photovoltaic panels.The financial-economic analysis is made based on dynamic methods which take into account the time factor and respect risk factors.