The impact of climate change on future Swedish heating and cooling demand

Abstract

The impact of the future climate is highly uncertain and depends on aspects such as future emission pathways and climate sensitivity. Today the average global temperature has already increased by 1°C, with the increase being even higher in Sweden [1]. Global warming influence weather parameters which in turn impacts other parameters such as biomass growth and power generation from renewable energy sources, but it also impacts the heating and cooling sector on the demand side. This thesis investigates how climate change impacts the Swedish heating and cooling demand by using an energy balance model to calculate how much energy is required to sustain an allowed indoor air temperature. The input to the model is a constant building stock and climate data regarding three different kinds of climates, the current climate, the climate at 1.5°C and 2°C average global temperature increase. The building stock data comes from the Swedish National Board of Housing’s project, BETSI and the climate data comes from different climate models from the World Climate Research Programme, CORDEX. The minimum allowed indoor air temperature is defined by guideline values from the Swedish National Board of Housing. Since there are no technical standards regarding maximum indoor air temperature in buildings in Sweden, the incentives for implementing a cooling system is based on health guidelines for indoor air temperature. From the output of the energy balance model results that indicates how the heating and cooling system could be affected by climate change are generated. The results show that the overall heating demand will be decreased between 5-13 % (-8.5 TWh) compared to the current scenario if the average global warming temperature is increased by 1.5°C and between 11-16% (-12 TWh) if the temperature is increased 2°C. The largest seasonal change occurs during winter time, and the smallest during the summer time. The cooling demand is increased with an increased average global temperature. At 1.5° average global temperature increase the cooling demand is increased 9-34% (+1.75 TWh) and at 2°C 10-40% (+2.25 TWh). The peak demand is slightly less affected by the changed climate compared to the yearly demand. There is a small change in the length of the heating period. In climate scenario 1.5°C the heating period is decreased 1.4-1.6% and in the 2°C climate scenario 2.1-2.2% demand decrease compared to the current climate scenario.