Abstract:
In line with the European Energy Performance of Building Directive (EPBD), this paper aims to calculate the
cost-optimal energy performance of a residential building in southern Europe, more precisely in Portugal,
taking into consideration thermal and lighting (daylighting and artificial lighting) refurbishment solutions. The
economic calculation method used considers the initial investment costs, the running costs (including annual
maintenance costs, operational costs, energy costs and periodic replacement costs), greenhouse gas emissions
costs and disposal costs. The results obtained for the energy needs allow choosing the cost-optimal package of
refurbishment measures. It is shown in this paper the relevance of daylighting and artificial lighting solutions
for the users’ indoor comfort, for the building energy consumption and, consequently, for the overall costs
during the building life span. From the daylighting and artificial lighting point of view, the most influent
factors are the type and solar optical glazing and the shading devices properties. For the adopted reference
building under Lisbon climate conditions and a North-South orientation façade, light-coloured external roller
blinds and single tinted blue-green glass solutions are the ones that lead, in the majority of cases, to
simultaneously lower values of global costs and energy consumptions.
