The combined effect of climate change and the urban heat island phenomenon is likely to reduce the space heating needs and cold-related mortality risk of urban populations in mid latitude countries during winter; however, it is also expected to increase overheating and heat-related deaths during summer. Identifying the determinant factors for energy demand and thermal comfort across a city is hence a key requirement for energy efficient retrofit and public health strategies. The aim of this thesis was to assess the relative impact of urban warming, built form and fabric characteristics on domestic energy use and overheating risk across a major city, using London as a case study. Two housing stock models were developed: a heat demand model based on steady-state energy use calculation techniques and a multiple linear regression overheating risk meta-model of an existing dynamic thermal simulation program. Input data was derived from existing Geographic Information System databases, national housing surveys and local urban air temperature models. The heat demand model successfully reproduced the ranking of urban areas based on their actual gas consumption (R² = 0.817) in a case study area containing 8.6% of London's dwelling stock. The heat island was found to decrease the average annual domestic heating load by 14% in these urban areas compared to a rural reference site. It was shown that the overheating meta-model can replicate the output of the thermal simulation program (R² = 0.763). It was indicated that highly exposed dwelling types, such as top floor flats and bungalows, as well as internally insulated buildings are likely to present an indoor overheating problem during periods of hot weather. However, the agreement between modelled overheating levels and monitored data collected in 101 London homes in summer 2009 was relatively weak, thus highlighting the modifying role of occupant controlled ventilation for indoor thermal conditions.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:625741 |
| Date | January 2012 |
| Creators | Mavrogianni, A. |
| Publisher | University College London (University of London) |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://discovery.ucl.ac.uk/1352829/ |
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