The paper presents the project management of the power supply for house electrical installation, with help of photovoltaic panels. Nowadays one of the solutions that could lead to solve the problem of energy is solar energy. The main solar energy capture devices are divided into two categories, namely: thermal solar panels that transform solar energy into thermal energy and after that it can be converted into electrical energy and photovoltaic panels that transform solar energy into electricity. This project uses photovoltaic panels and the calculation of energy requirements are made for an electrical installation of a house. The reflection coefficient of the photovoltaic panels is calculated with the proposed method.