Integration of renewable energy systems in urban buildings: From energy conservation to feasible energy supply

The integration of renewable energy systems, mainly active solar ones, in buildings has been an aim of intense research over the last thirty years. Solar thermal systems have become the most widespread, and certainly the most well known RES system, being a commonly accepted solution for hot water production. Within the framework of this paper, which is based on the results of the SEPEDIC-ALTENER project and the Serres project are being analysed all the aspects of RES systems integration in buildings. Aim of these projects was to determine the potential, the obstacles and the chances for sustainable development of small and medium-sized urban communities, by means of RES implementation. The analysis discussed in the paper is focused on the use of active solar systems for space heating and space cooling of residential and commercial buildings. This was done by assessing the available technologies, as well as by discussing the difficulties of sizing the collectors and the storage vessels needed to enable the integration of such systems.