Climate Zones Classification for Buildings Energy Efficiency Assessment

The definition of the building climate zones is the basis for studying the effects of urban climate on building energy consumption and efficiency. In Spain, the transposition of the European Directive on Energy performance of buildings (Directive 2010/31/EU) has been carried out through the Technical Building Code (CTE), which divides the territory into climatic zones through which it evaluates the energy performance of buildings. However, the CTE carries out a climatic division based on administrative criteria ("provinces", NUT3), which leads to oversimplifying the Spanish climatic reality.

In this sense, the paper develops a new methodology for classification maps of climatic zones of buildings in Spain in order to improve the CTE. Therefore, the application in Spain of the CTE, Köppen and ANSI / ASHRAE methodologies are critically studied and compared. A first approach shows inadequacies that could be improve to optimize the energy efficiency of buildings. The climatic data for Spain -provided by the European Climate Assessment & Dataset Project (https://www.ecad.eu/) since 1950 (with a resolution of 1 km²/pixel) are analyzed, and a series of climatic indicators are established (such as the number of summer days, tropical nights, heating degree days, …). Next, OLS and cluster analysis are used as a method to define the Spanish climatic zones. Finally, the research proposes a new climate zones classification for Spain. The new classification provides more detailed climate information for building energy efficiency research and improves the classification defined in the CTE.