What is sustainable cooling and how can it help tackle the climate crisis?

Scorching heatwaves, more and more intense droughts, wildfires and other weather extremes… the signs of the climate crisis are all around us. But sustainable cooling could help beat the heat while cutting emissions.

Rethinking how we stay cool could contribute to tackling today’s cooling paradox - in which heatwaves and extreme temperatures caused by the climate crisis send people in many parts of the world rushing to switch on air conditioning units, which release gases that contribute to climate change

As the name suggests, sustainable cooling is more climate-friendly than traditional refrigeration. It targets efficiency improvements to cooling solutions alongside measures that lower ambient temperatures in buildings and urban environments.

Traditional air conditioners and refrigerants contain fluorinated gases that can leak, depleting the planet’s ozone layer and harming the environment. Sustainable cooling replaces these gases with climate-friendly alternatives, which when coupled with enhanced energy-efficiency measures reduce both direct emissions from refrigerant leakage and indirect emissions from the energy used to power the cooling unit.

According to the UN World Meteorological Organization, 2022 was one of the hottest years on record, with the past eight years the hottest since records began.

Climate change and nature’s collapse dominate the World Economic Forum’s Global Risks Report 2023 list of top-10 long-term threats, with these concerns occupying the top four places.

As our planet’s atmosphere warms, heatwaves, soaring temperatures, droughts and other weather extremes are becoming both more frequent and more intense.

Global warming has made simultaneous large heatwaves in the Northern Hemisphere six times more likely over the past 40-year period, according to research published in the Journal of the American Meteorological Society.

Furthermore, cooling is critical to comfort, productivity and health. Cooling is needed in agriculture to ensure food security and hospitals and healthcare centers need cooling to transport vaccines and other medical products.

A rethink of building designs and city layouts can play an important role in sustainable cooling.

Ambient cooling puts measures in place to help nature reduce the sun’s intensity, such as covering building roofs, balconies and other areas with plants and greenery to absorb heat, and fitting insulation and double glazing to block the sun’s heat.

In urban areas, adding green spaces, installing shade cover and planning wide urban streets and low buildings to increase wind flow-through, are among the many measures that help to reduce heat gain.

Some sustainable innovations, as explained by organization Sustainable Energy for All (SEforALL), use no operational energy or refrigerants. These are sometimes referred to as nature-based or passive technology solutions.

For instance, WAVIN (MetroPolder), a World Economic Forum Uplink innovator, builds green roofs that capture and store rainwater, which is recycled for use in cities. Captured rainwater is used for everything from irrigating the greenery on the roof, flushing the building’s toilets, and cooling the building during summer heat.

Urban climate-tech start-up BioShade reimagines how cityscapes look and feel, using AI, IoT and hydroponic technologies to autonomously generate natural shade. Roofs, walls and urban spaces become green, living organisms that create a cooler microclimate.

Sustainable cooling can also leverage a more efficient use of refrigerants. These technologies use certain types of refrigerants (such as ultra-low Global Warming Potential (GWP) natural refrigerants) and depend on clean energy sources. Additionally, special features often help maximize the delivery of cool air, to save energy.

Cooling technologies like refrigeration and air-conditioning could account for two-fifths of Southeast Asia’s electricity demand by 2040, according to a report called Freezing in the tropics: Asean’s air-con conundrum. Rapid growth in economic output, wealth and population density, and increasing migration to cities prompts heavy reliance on cooling solutions in the burgeoning economies of regions like Asia.

Driving progress on sustainable cooling requires a policy framework that encourages people, businesses and local governments to go green, including sustainable building codes and tax incentives, grants and subsidies to encourage take-up.

According to the UN, policymakers can incentivize businesses to create energy efficient cooling products, all while working sustainable cooling into climate pledges and ensuring that sustainable cooling is considered during the planning and design energy, urban, transport, agricultural and health service projects.

To be sure, finance for sustainable cooling technologies and initiatives is another must have. Many poorer households and rural communities are disproportionately impacted by extreme heat and have fewer resources to put energy-efficient or nature-based cooling solutions into place.

Cooling currently contributes to 3.4% of global emissions. Additionally, the International Energy Agency estimates that "Climate friendly cooling" could sidestep more than 460 billion tonnes of greenhouse gas emissions – or approximately eight years of global emissions at 2018 levels

Of course, there's no one-size-fits-all solution to scale sustainable cooling. Tackling this issue will require a combination of strategies and empowering local leaders to work quickly to craft lasting solutions that work for their locality.

But while these steps will take leaders of all stripes in the right direction, urgent action is needed to address the underlying causes of climate change to keep global temperatures within the Paris Agreement climate target.