Long term evaluation of building energy performance : comparison of the test reference year and historical data series in the North Italian climates

The pursuit of better energy performance of buildings led o the recourse to more detailed instruments of analysis, requiring more complex and detailed inputs, such as the hourly weather data. In this work, the representativeness of the test reference year (TRYEN) weather data, recently developed in Italy in accordance with the procedure proposed by EN ISO 15927-4:2005, has been studied evaluating the energy performance – energy needs and peak loads – of a set of different simplified reference buildings by means of TRNSYS simulation code, using both the TRYEN and the TRYEN source multi-year collected weather series for 5 north Italian locations. The results have been analysed by means of both descriptive and inferential statistics. The variability of energy performance has also been correlated with the envelope characteristics, in order to estimate a sensitivity of the different buildings to the weather data variability.