Impact of outdoor humidity conditions on building energy performance and environmental footprint in the degree days-based climate classification

Abstract

Climate classification for buildings plays an essential role in providing energy efficiency policies enforced through building energy standards, codes, and the related voluntary above-code programs, as well as in achieving decarbonization goals. Through an analysis of code-compliant office models in 801 locations in the US in this paper, first, a systematic difference is identified in building energy use, and its corresponding environmental footprint, in different locations within the same ranges of heating and/or cooling degree days but with different humidity conditions. The results show that the source energy consumption vary up to 1671 GJ (47%, excluding the equipment load) in two locations with the same climate zone but different moisture conditions. This is due to the deficiency of the degree days in predicting building energy consumption and results in a disproportionate assignment of energy efficiency measures. Second, besides similar trends when comparing the averages in subtypes, the variations in emissions within one climate zone and subtype can be over 10 times for CO2 and 6 times for SO2 as opposed to site energy consumption with less than 1.8 maximum variation, which signifies a substantial importance of geographic prioritization in carbon-neutral policies for the electricity providers along with climatic parameters.