Effects of climate changes on building energy demand and thermal comfort in Canadian office buildings adopting different temperature setpoints

Office buildings are responsible for a substantial portion of the energy demand in the commercial sector. To better understand and address the impacts of climate change on their energy demand and comfort levels, this paper investigates office buildings located in extremely cold, cold-humid, and cool-humid Canadian climate zones. Building energy simulations are performed using climate projections for the 2056–2075 period. The effect of extending thermostat setpoints, as a demand response strategy on reducing energy demand, is also studied under future climate conditions. The results quantify the expected decrease in the heating and the increase in the cooling loads due to the future warmer temperatures across Canada. However, the magnitude of change varies significantly among the three selected climate zones. In fact, extending the temperature setpoints would reduce the annual energy demand by 0.9–8.7% in Quebec City, 1.6–9.1% in Toronto, and 1.4–9.9% in Vancouver. For all three selected cities, extending the temperature setpoints result in a substantial percentage of zones with a predicted mean vote (PMV) outside of the ±0.5 range. The benefits of increased levels of insulation for reaching thermal comfort during cold winter days and the penalty that would occur in summer days are assessed. Finally, the greenhouse gas emissions for the present and forecasted future energy demand of heating and cooling are determined.