This paper presents a common approach for involving renewable energy sources and unit commitment problem solving in a dispersed power system on the example of Kazakhstan as a factor of the energy sector sustainable development. The methodology includes analyzing of the impact of the regional and global energy trends, legislation and the potential for renewable energy sources. The numerical results show the possibility of solving the problem of unit commitment with renewables with the least operating costs and with the most optimal renewable energy source type in the region. Also, the possibilities of autonomous operation of a part of the dispersed power system with a certain combination of renewable energy sources and electric power storage and covering the electricity deficit from the renewables instead of commissioning of traditional energy sources are shown. We show that solving the problem of electricity deficit in the region with the help of renewable energy, sustainable development of the energy system can be ensured and the impact on the environment can be minimized.