Evaluation of Building Retrofit Strategies in Different Climate Zones

Buildings account for over 40% of carbon dioxide (CO2) emissions in the United Kingdom and around 25% in China. In an attempt to mitigate global warming and reduce greenhouse gas emissions, the UK government is committed to reducing its greenhouse gas emissions by 80% below the 1990s level by 2050; China pledged a 40% to 45% decrease in CO2 emissions per gross domestic product (GDP) by 2020 against 2005 levels. One efficient way to improve building energy efficiency and the associated CO2 emissions is building retrofitting. This study aims to assess two levels of deep retrofit plans in typical office buildings to evaluate the potential energy savings that can be achieved. These retrofit scenarios are assessed using numerical simulation of prototypical buildings in five climate zones in China as well as London and Aberdeen in the UK. Numerical simulations have been conducted using EnergyPhis software. The outcomes of this study reveal that deep retrofits in office buildings can potentially achieve the target of 50% energy reduction compared with the source energy consumption of buildings designed in the 1980s. However, economic factors should also he considered in the process of decision making to choose the most appropriate building retrofit strategies.