Solving the Global Cooling Challenge

The report warns that room air conditioner (RAC) stock could grow from 1.2 billion to 4.5 billion units by 2050, potentially increasing global temperatures by 0.5°C by 2100. It argues that conventional efficiency improvements and the Kigali Amendment are insufficient to offset this growth. The authors propose a '5X solution'—technology with five times less climate impact than current standards—which could prevent 100 gigatons of CO2e emissions by 2050 and save US$1.4 trillion in power generation capital costs.

• Global room air conditioner (RAC) stock is projected to increase from 1.2 billion units today to 4.5 billion units by 2050, with developing countries experiencing a five-fold increase in demand.
• The growth of RACs poses a significant risk to global temperature goals, with the potential to cause an increase of over 0.5°C in global surface temperatures by 2100.
• Under a business-as-usual Reference Scenario, global electricity consumption for RACs is projected to rise from 2,300 terawatt hours (TWh) in 2016 to 7,700 TWh in 2050.
• Meeting the peak demand from RAC growth by 2050 would require 2,000 gigawatts (GW) of new generation capacity, representing an estimated US$1.2 trillion in capital spending.
• Cumulative emissions from RACs are estimated at 132 gigatons by 2050 in the Reference Scenario, and up to 167 gigatons if the grid emission factor remains constant.
• The Kigali Amendment is expected to reduce cumulative CO2e emissions by 23 gigatons by 2050, but it primarily addresses direct refrigerant emissions rather than the larger indirect emissions from electricity.
• Conventional strategies, including building codes and incremental efficiency gains, are insufficient, providing only about 40 gigatons of emission reductions by 2050, which is roughly half of the 75 gigatons needed to neutralize RAC growth impacts.
• The proposed '5X solution'—technology with five times less climate impact than current standards—could prevent up to 100 gigatons of CO2e emissions by 2050 and mitigate up to 0.5°C of global warming by 2100.
• Adopting the 5X solution could eliminate the need for 2,000 GW of new power generation capacity, saving approximately US$1.4 trillion in capital investments.
• A 5X efficiency level is technically achievable by combining vapor compression enhancements, free cooling, advanced dehumidification, and solar PV integration with low-GWP refrigerants.

APA

Campbell, I., Kalanki, A., & Sachar, S. (2018). Solving the Global Cooling Challenge. RMI. https://rmi.org/app/uploads/2018/11/Global_Cooling_Challenge_Report_2018.pdf

Chicago

Campbell, Iain, Ankit Kalanki, and Sneha Sachar. Solving the Global Cooling Challenge. RMI, 2018. https://rmi.org/app/uploads/2018/11/Global_Cooling_Challenge_Report_2018.pdf.

Wikipedia

{{cite report |last1=Campbell |first1=Iain |last2=Kalanki |first2=Ankit |last3=Sachar |first3=Sneha |title=Solving the Global Cooling Challenge |publisher=RMI |date=November 2018 |url=https://rmi.org/app/uploads/2018/11/Global_Cooling_Challenge_Report_2018.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{campbell2018solving, author = {Campbell, Iain and Kalanki, Ankit and Sachar, Sneha}, title = {{Solving the Global Cooling Challenge}}, institution = {RMI}, year = {2018}, month = nov, url = {https://rmi.org/app/uploads/2018/11/Global_Cooling_Challenge_Report_2018.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }