DualSun's mission is to make the buildings in which we live energy self-sufficient through the local production of heat and electricity. Photovoltaic solar is developing exponentially in the world. Its price, more and more competitive compared to traditional energies, allows it to establish itself as a means of covering the electrical consumption of buildings. Alone, however, it is not enough because buildings also need heat: both for heating, but also and above all to meet the demand for domestic hot water. Being able to provide systems that offer both electricity and heat to move towards energy-positive buildings, all on roof surfaces that are not infinite, this is the meaning of the mission at DualSun.