Overheating of cities is causing serious energy, environmental and health problems and it has a serious impact on the whole economic and cultural life of cities. To counterbalance the impact of high urban temperatures several mitigation technologies have been proposed, developed and implemented.
Conventionally in building performance simulations (BPS), it is assumed that air entering outdoor HVAC equipment is at the outdoor ‘ambient’ temperature, obtained from a weather file. However, significant spatial variations exist in outdoor air temperature fields, especially within the thermal boundary layers that form near exposed surfaces like roofs.
It has become increasingly important to study the urban heat island phenomenon due to the adverse effects on summertime cooling energy demand, air and water quality and most importantly, heat-related illness and mortality. The present article analyses the magnitude and the characteristics of the urban heat island in Sydney, Australia. Climatic data from six meteorological stations distributed around the greater Sydney region and covering a period of 10 years are used. It is found that both strong urban heat island (UHI) and oasis phenomena are developed.
This project investigates hybrid solutions using enhanced ventilation in order to achieve indoor comfort conditions, reduce energy consumption and carbon emissions, and finally test it in a selected school building located in Sydney, which co-funded this project. In order to achieve this objective, the following activities were carried out:
Cool roof technology is known to reduce the cooling energy consumption of conditioned buildings during hot periods, and widespread implementation of such roofs in a neighbourhood or precinct can mitigate the urban heat island effect.
The present study is aiming to pre-design and optimize a smart climatic street in Parramatta, named Phillip st., exhibiting high climatic, environmental, and energy performance.
The specific objective of the study is to propose, investigate, and optimize the combination of advanced thermal mitigation and smart technologies to improve thermal comfort and mitigate the urban overheating in the area.
To satisfy the above described objective, the whole study involves the following research phases:
The implementation of ‘cool’ roofing materials, with high solar reflectance and infrared emittance, has received significant attention in recent years, as a method to mitigate the urban heat island effect and reduce building cooling energy requirements. The effect of ‘cool’ roofs on heat transfer through the roof structure has been investigated by many researchers. However, the air temperature field above roofs and the influence of elevated above-roof air temperatures on the performance of rooftop air-conditioning equipment and photovoltaic panels have not been studied in depth.
This document presents the mitigation study for the CBD area of Darwin, performed by the High Performance Architecture Group of UNSW, Faculty of Built Environment.The first part of the report includes the methods and the results of the terrestrial and aerial monitoring campaign, the evaluation of the magnitude of the Urban Heat Island (UHI) and finally the main conclusions on the climatic context characterized with the monitoring.