Modern society has a growing need for the electricity. To protect the environment, future energy demand must be met with more environmentally friendly technologies, such as renewable energy sources. Because of its vast availability, solar radiation has been used for decades to generate electricity through photovoltaic systems (PV) for residential, educational, and commercial buildings. However, the growth of distributed generation (and renewable energy sources) across power systems in industrialized countries has created new challenges. Random renewable generation causes an imbalance between electricity production and consumption, so smart grids and microgrids may be solutions. In this article, we investigate improving the energy efficiency in the Faculty of Electrical Engineering building in Osijek by using a microgrid. To do so, we compared the total electricity consumption of the building and the production of a 10 kWp photovoltaic power plant on that building. The improvement in energy efficiency of the building produced a maximum savings of up to 10% of the building’s total electricity consumption.