Keeping cool in record heat, without further warming the planet

Posted on September, 09 2022

As temperatures continue to rise and heatwaves become more severe and frequent, the world will need to do more to keep cool. There are ways to cool our homes and businesses without further fuelling the climate crisis, writes Richard Scotney, WWF Global Energy Efficiency Lead.
The climate crisis is driving increasingly extreme heat across the world. This summer in Europe was officially the hottest on record. In May, temperatures in South Asia reached 50 degrees in some cities. In South East Asia, people living in an already hot climate are going to suffer from further heat waves due to climate change. Wildfires across the world continue to threaten people and nature – last month, fires in the Amazon were at the highest level in a decade, while wildfires in Australia in 2019-20 killed or displaced three billion animals. 

Growing temperatures, along with rising incomes will see further increasing demand for electricity for air conditioning. In Singapore, cooling is already responsible for 30% of electricity use, according to a recent WWF-Singapore report. Low rates of air conditioning use by households in Cambodia, Vietnam and Indonesia mean 260m new ACs are expected to be installed in the region by 2014, compared to less than 50m today. In India, emissions from building cooling are expected to grow sevenfold by 2050 compared to 2017. 

However, there are solutions to ensure people have access to cooling, but without dramatically increasing the level of emissions.

Passive cooling


Firstly ‘passive cooling’ solutions are those which don’t use air conditioning, but rather use shade, building design and air flows to keep people cool. A tree is the simplest example, with temperatures under a tree being 7-15 °C lower than in the sun. The University of Oregon estimates that passive cooling strategies can reduce the load on air conditioning by as much as 80%. WWF has demonstrated how nature-based solutions in cities can bring about cooling, in South Africa and in the flagship report ‘beating the heat’.

WWF is launching a new project in Cambodia on energy efficiency in the hotel industry. Already we have seen the difference in energy bills which can vary up to tenfold between those hotels which have been designed to use passive cooling solutions against those that don’t. In Cambodia, many hotels, even some luxurious ones, use traditional cooling techniques, particularly relying on trees, air flows and water, which saves money and reduces carbon for the hotel owner. In India, a country suffering greatly from extreme heat, WWF has outlined in detail the different low carbon solutions for buildings with a focus on passive designs. 

Efficient air conditioning


We need to ensure air conditioning systems are as efficient as possible. Indeed, efficient systems can reduce future energy consumption growth from cooling by 45%. In Europe and Latin America, WWF partners with Topten to inform customers and policy makers of the efficient appliances, including air conditioning units, there are on the market. These efforts are estimated to have reduced emissions by over 50m tonnes of C02 - higher than Sweden’s annual CO2 emissions. Recently, Topten published templates for officials for public procurement of air conditioning systems, which complements other sustainable procurement guidelines such as those of U4E

Flexible cooling


Expanding into new flexible cooling technologies will also be important. Air conditioning in certain tropical countries is now the main source of peak energy demand.  A recent report from WWF-Singapore and the Carbon Trust highlighted the importance of flexible clean cooling solutions for the energy transition – including district cooling, control systems for demand-side response management, Phase change materials for short-medium duration storage capacity and Cryogenic energy storage systems for long duration storage capacity. 

Behaviour change


Changing individual behavior is a challenging but important area. In WWF Cambodia’s office, 70-80% of our electricity consumption is from air conditioning. Using comfort fans, which use 50x less electricity than an air conditioning unit, in the morning hours when temperatures are lower can dramatically decrease electricity consumption. In addition, programming air conditioning systems at higher, but still comfortable temperatures can reduce air conditioning use. The Spanish government has set a minimum temperature of 27 degrees, in line with similar campaigns in Italy and Japan.

Ultimately, the solutions above need to work in tandem, with comprehensive plans to have passive cooling, efficient appliances, new innovations and behavior change. 
  • At the country-level, this is typically through development of National Cooling Action Plans. In Pakistan, WWF is working with the government and partners CLASP and HIMA Verte, to develop this National Plan. 
  • At the city level, several cities have now recruited chief heat officers to deal with extreme heat. The WWF’s One Planet City Challenge works to raise the profile of climate friendly solutions for, including working with Cities on energy efficiency plans in Philippines and Indonesia. 
  • With businesses, WWF is working with supermarkets in Indonesia, Starbucks chains globally and with the Cambodian hotel sector to look at how to reduce demand from cooling.
  • At the global level, the Clean Cooling Coalition, WWF is an active participant in, works with multiple actors to ensure the world can provide access to more people for clean cooling.
The demand for cooling will rise, particularly as extreme heat rises, but we do need to keep demand growth lower to keep emissions within 1.5°C. At WWF we are working internally, with governments, partners and the private sector to tackle this challenging but critical problem. 
Digital screen showing 40 degrees Celsius
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