Investigation Of The Urban Heat Island And Its Impact On Energy Consumption In Makkah City In Saudi Arabia

Abstract

Unsustainable urbanisation and rapid development exacerbate thermal environmental issues, contributing to climate change and raising temperatures in cities compared to surrounding rural areas. The aim of this study is to investigate the urban heat island (UHI) effect in Makkah city by using a field measurement approach. According to the air temperature and relative humidity data in the study area, this research evaluates the reciprocal interaction between UHI and building energy consumption in urban areas. Three key factors impact the form of the UHI: vegetation, urban building forms, and surface materials. Due to the cooling down from Al-haram the Great Mosque, which influences the temperature in the surrounding environment, the city centre is colder than the rural areas. As a result, the urban areas have been divided into two study areas: the central area and the neighbourhood areas. According to the observation, for neighbourhood areas, the monthly average UHI intensity values in Makkah city ranged between 0.8 °C and 2 °C during the investigating period from May 2019 to the end of April 2020. The basic algorithms have been applied by using the Excel solver in Microsoft software to produce weather files central and neighbourhood areas. Furthermore, the study found that the UHI impact is more significant on summer days than on winter days. The findings also demonstrated that the night UHI impact is substantially stronger than the daytime UHI effect. In this investigation, an algorithm is used to predict the UHI intensity for each location compared to a reference site by linking factors such as distance from the city centre, surrounding albedo, and the sky view factor. A modified typical meteorological year (TMY) has been generated based on the hourly air temperature and relative humidity measured at strategically locations across the city. The study used a case study of a residential villa as the typical Makkah house to assess the effect of UHI on urban building energy consumption. As a consequence of the UHI effect, the cooling demand in Makkah's neighbourhoods areas increases 4% annually.