Towards cost-optimal nearly zero-energy buildings

The building sector is one of the key sectors to achieve the 20/20/20 targets of the European Union (EU). Beyond these targets, Europe also aims at bringing about drastic reductions of greenhouse gas emissions in the residential and service sectors of 88% to 91% compared to 1990 by 2050.
With the recast of the Energy Performance of Buildings Directive (r-EPBD) (European Parliament and Council 2010), the framework has been set to proceed along this track. Two mechanisms will be decisive for the development of the building sector: the principle of nearly zero-energy buildings and the principle of cost-optimality.