A rapid evaluation method for design strategies of high-rise office buildings achieving nearly zero energy in Guangzhou

The construction of nearly zero energy buildings (NZEB) has achieved dramatical impact on global warming and energy crises. It is still a challenge for designers to derive design strategies on how to achieve NZEB in the early design stage, because a complex modelling process with many input parameters of the current NZEB design and evaluation tool is still unavoidable. This article, therefore, aims to introduce a tool suitable for the rapid and reliable evaluation of NZEB design strategies for high rise office building in the city of Guangzhou in China. Firstly, a high-rise office building with typical geometry features is established by sensitivity analysis and survey, thereby the reference building consumption is obtained. Secondly, comprehensive simulations on cases with various envelope features, air conditioning performances and lighting control methods is carried out. Based on the sensitivity analysis on simulation results, key influencing parameters are selected out, effective strategies which fulfills "Technical standard for nearly zero energy buildings (NZEBTS)" are put forward. Finally, a parametric building energy evaluation model is built by regression analysis on simulation results. Combined with energy efficiency index from "NZEBTS", an evaluation tool is developed to help designer determine NZEB strategies. The results revealed that the most effective strategies to achieve NZEB in Guangzhou are to apply high performance external windows, improve air conditioning systems and utilize intelligent zone-controlled lighting systems, meanwhile, the utilization ratio of renewable energy (eta(s)) should be more than 40% of building total annual energy consumption.