Climate change impact on energy savings in mixed-mode ventilation office buildings in Brazil

Abstract

With the projected increase in temperature, coupled with the rise in intensity and frequency of heatwaves caused by climate change, it has become essential to investigate the impact of climate change on building energy consumption and thermal comfort. This study focuses on office buildings with mixed-mode ventilation in Brazil as a case study. Using a typical 15-story office building archetype for various Brazilian cities, considering current and predicted scenarios (2050 and 2080), the potential for energy savings through natural ventilation was assessed. It was observed that the average increase in temperature and wind speed in the predicted climate varied in each city and showed significant variations over the years. Predicted projections under high-emission scenarios (SSP5-8.5-2080) reveal significant increases in energy consumption, highlighting the vulnerability of cities like Belo Horizonte, which could face a 77% increase in total energy consumption. Additionally, the analysis of HVAC hours of use over time indicates a progressive increase, suggesting a potential reduction in natural ventilation as a mitigation strategy. Mitigation measures, especially in the SSP1-2.6 scenario, are crucial to stabilize HVAC consumption and preserve the use of natural ventilation, emphasizing the importance of sustainable approaches to address the energy challenges arising from climate change.