Realistic pathways to decarbonization of building energy systems

Abstract

<h2>Summary</h2> There is a pressing need to decarbonize our energy sector to limit the effects of climate change. Electrification in the buildings and transportation sectors is being proposed as a critical solution. This paper discusses the impact of rapid electrification by comparing the predicted future electricity demand with different scenarios for electricity generation. The effects on primary energy consumption and CO₂ emissions are highlighted. Our analysis shows that the composition of the electricity grid plays a key role in determining a better trajectory toward decarbonization. Another key challenge facing the building energy sector is the eventual phasing out of synthetic refrigerants currently used in vapor-compression heating, ventilation, and air-conditioning (HVAC) systems. This article discusses potential solutions for the building energy sector to address these issues and provides engineering solutions that can guide the safe transition to a decarbonized economy without catastrophic shortages of supply or exacerbation of CO₂ emissions. Overall, the paper determines that an ∼5.0 quad reduction in building energy usage can be achieved by switching to carbon-free thermal energy where possible and implementing technologies such as desiccant-coated heat exchangers to judiciously manage dehumidification loads. The entirety of the energy saving methods recommended in this article allows for a reduction in predicted carbon emissions by up to 67%, which, combined with carbon capture and other energy saving techniques, could approach a goal of carbon neutral by 2050.