A comparison of typical meteorological year (TMY) data files for different regions of a city

Abstract

A typical meteorological year (TMY) is a set of hourly values of solar radiation and meteorological data determined from historical observations that is representative of the long term climate of a location. A TMY is generated using statistical methods to select individual 'typical' months from different years from the period of record; these typical months are concatenated to form a complete year of hourly data. TMY data files are commonly used to represent outdoor weather conditions in building energy simulations that assess a building's thermal performance, energy consumption and load profiles. A key element in building energy simulation is the incorporation of detailed weather information such as a TMY that is representative of the local climate. It is common for just one TMY data file, usually calculated using data from the city's main meteorological observation site, to be used for all building energy simulations within a city, regardless of the location of the building. This practice disregards micrometeorological variability across a city that may have significant impacts on a building's energy needs. In this study TMY data files are compared for three sites across Hong Kong- a highly urbanized site characterized by compact high-rise buildings; a less urbanized site characterized by dispersed low-rise buildings and farmland; and a site located on one of Hong Kong's inhabited outlying islands. All three sites experience significantly different meteorological conditions. The development of these TMY data files allows for assessment of building energy consumption that incorporates micrometeorological variability within the city.