Conventional energy sources are not renewable sources and are quickly depleted. They pollute the environment and accelerate the process of global warming and climate change on Earth by emitting greenhouse gases. Renewable energy sources, unlike conventional ones, have a much smaller impact on the environment and are unlimited energy sources. Solar energy is the driver of all life and climate processes and in the near future could become the main carrier of environmentally sustainable energy development due to the very high solar radiation potential. Solar energy along with hydropower and wind power is the purest source of energy of the future. In this paper, it is necessary to dimension an autonomous photovoltaic system on the example of a low-energy family house located on the Adriatic coast. It is necessary to describe the process of direct conversion of solar energy into electricity using the photovoltaic effect in photovoltaic cells. In this paper, it is necessary to select the appropriate components of an autonomous photovoltaic system and adjust them to the annual electricity consumption in the household. The geographical position of the conceptual design of the family house and the amount of irradiation should be taken into account. Finally, the possibility of monitoring the position of the Sun for better system optimization and connection to the public electricity grid should be considered.