The background of this article is the potential energy savings of solar heat supply systems due to the use of the renewable energy of solar radiation. The motivation is to create a solar collector design that would combine the functions of both a building cover and a solar collector. It is necessary to investigate and compare different types of solar collector coatings (traditional and modern) and pipe diameters. The purpose of the article is to solve aspects of energy efficiency for new eco-friendly solar collectors. The most effective result occurred with the solar collector covered with the rubber–graphite composition of Grafplast PDA, and when using Prandelli/Tuborama pipes with a diameter of 0.016 m. Their efficiency increased by 8% compared to the second version of the collector made using a more traditional solution. The influence of the distance between the pipes and the flow rate of the heat carrier on the efficiency of the solar collectors was evaluated.