Should we be using just 'typical' weather data in building performance simulation?

Abstract

Over the past 40 years, organizations worldwide have created weather data sets specifically for use in building energy simulation, usually called typical or reference years. Crawley (1998) showed how a variety of typical data sets compare in terms of impacts on building energy. This study found that TRY-type files (single years) do not represent the period of record well and recommends TMY or other weather data created using similar procedures, such as European test reference years. Several other studies have concluded that TMY are good enough to represent typical building operation. Yet we need weather that represents a reasonable range of climate conditions that buildings experience. A 2015 study proposed development of eXtreme Meteorological Year (XMY) weather files to represent the range of climate conditions that buildings may experience. An XMY starts with the same period of record as the TMY, but the methodology purposely selects more extreme months. This paper proposes a new regime for climatic data representation in buildings-an XMY or eXtreme Meteorological Year. We demonstrate how several sets of international typical meteorological data sets compare to the actual period of record that they represent. Then using prototype buildings, we show that the climatic response of the building would be better served by a range of building climatic data, investigating high and low cases of temperature, humidity, solar radiation and wind conditions.