Temporal and spatial characteristics of the urban heat island in Beijing and the impact on building design and energy performance

With the increased urbanization in most countries worldwide, the urban heat island (UHI) effect, referring to the phenomenon that an urban area has higher ambient temperature than the surrounding rural area, has gained much attention in recent years. Given that Beijing is developing rapidly both in urban population and economically, the UHI effect can be significant. A long-term measured weather dataset from 1961 to 2014 for ten rural stations and seven urban stations in Beijing, was analyzed in this study, to understand the detailed temporal and spatial characteristics of the UHI in Beijing. The UHI effect in Beijing is significant, with an urban-to-rural temperature difference of up to 8 °C during the winter nighttime. Furthermore, the impacts of UHIs on building design and energy performance were also investigated. The UHI in Beijing led to an approximately 11% increase in cooling load and 16% decrease in heating load in the urban area compared with the rural area, whereas the urban heating peak load decreased 9% and the cooling peak load increased 7% because of the UHI effect. This study provides insights into the UHI in Beijing and recommendations to improve building design and decision-making while considering the urban microclimate. •Temporal and spatial characteristics of urban heat island in Beijing is studied.•Statistical analysis of the 50-year 17-station weather data is performed.•Correlation is found between UHI and the occurrence of extreme events.•Impacts of UHI on peak demand and energy use in buildings are evaluated using simulation.•It is recommended to use local weather data for building design and performance simulation.