Buildings are one of the major consumers of energy in Europe. This makes them an
important target when aiming to reduce the energy consumptions and carbon emissions. The
majority of the European building stock has already some decades and so it needs renovation in
order to keep its functionality. Taking advantage of these interventions, the energy performance
of the buildings may also be improved. In Portugal the renovation techniques, both regarding
energy efficiency measures as well as measures for the use of renewable energy sources, are
normally planned at the building scale. It is important to explore the possibility of having large
scale interventions, has it has been done in other countries, namely at neighbourhood scale with
district energy system in order to optimize the results in terms of costs and environmental
impact.