• A POSTnote on sustainable cooling will look at how we can sustainably cool homes and goods in a warming world.
  • It will review UK preparedness, balance cooling needs against electricity demand and carbon goals, and explore solutions.
  • Provisional start date April 2020: To contribute expertise, literature or an external reviewer please email Jack Miller.

Under existing international emissions pledges, the average level of global warming could reach 3°C by the end of this century, and temperatures could be rise by much more at specific times and places. Moreover, heatwaves are projected to be more intense and occur more frequently under any level of warming. Risks to human health from overheating are widely recognised both internationally and in the UK. The 2018 Climate Change Risk Assessment identified the lack of preparedness of UK homes for future temperature rise as a key domestic risk from climate change. Globally, demand for cooling is likely to increase substantially from space cooling requirements and data centres. Moreover, affordable cooling is needed to refrigerate food products, vaccinations and other medical products, and is hence essential for meeting sustainable development goals around hunger, prosperity and health.  

At least 1 billion people globally face immediate risks from lack of cooling access, and researchers have highlighted the additional 2.3 billion growing middle class, whose limited purchasing options mean they may only be able to afford less expensive and less efficient cooling devices. Global electricity demand for cooling in 2018 was around 2100 terawatt-hours – almost as much as all the electricity consumed by G8 countries during the same year. Demand is growing exponentially, and it has been estimated that energy demand for cooling could equal that of heating by mid-century if the energy performance of relevant technologies is not improved. In addition to implications for climate change from this energy demand, there are concerns around leakage of refrigerant “F-gases” from low-quality products, which could adversely ozone coverage and are themselves potent greenhouse gases.  

Incremental improvements in the performance of electrical air-conditioning units alone (which are energy-intensive and hence responsible for substantial CO2 emissions) could help to address these issues. However, researchers highlight the importance of more innovative approaches, such as using district and ‘waste’ cooling, building designs that maximise natural ventilation, and changing user behaviours. This POSTnote will outline the scale and scope of the cooling challenge, as well as possible solutions from a technical, sociological and commercial perspective. It will examine how these could affect the UK, as well as international perspectives.