FEW PLACES on Earth are more familiar with the deadly consequences of extreme heat than countries in Africa. Heat kills crops, spoils food and medicines, and makes it impossible to work, study or sleep. As the planet warms, the number of days when people on the continent will be exposed to excessively high temperatures is set to rise. How will they keep themselves, their food and their medicines cool?

One answer is air-conditioning, which Lee Kwan Yew, Singapore’s founding father, once credited with changing “the nature of civilisation by making development possible in the tropics.” Yet air-conditioning, while cooling people, worsens global warming through power use and refrigerant leakage and by warming the area around air-conditioned buildings. It also remains inaccessible to most Africans. Only half the population has grid power. Even where it is stable, the cost of running an air-conditioner is forbiddingly high, partly because lax regulation means most are energy-intensive and inefficient. Only 5% of African homes have a unit, a percentage that has barely budged in two decades.

As temperatures and incomes rise, that number is likely to rise, and efforts are under way to make air-conditioning more sustainable. Yet given the unstable grid, lack of money and the need to limit emissions of greenhouse gases, other ways of keeping cool will be needed, too.

For now, much climate-friendly innovation is concerned not with cooling people, but with ensuring that heat does not spoil their food and medicine. Cameroon and Sierra Leone use solar-powered fridges to keep vaccines and other temperature-sensitive medicines stable. Combined with battery storage, they stay cool even when there is no sun or alternative power supply. Some freeze water into an ice lining, meaning they do not even need batteries. Supplied to the Democratic Republic of Congo during the covid-19 pandemic, they can now be used for mpox vaccines.

Similar efforts are under way in agriculture, where up to 18% of harvests are currently lost to insufficient cold storage. Some startups are offering farmers space to rent in solar-powered cold rooms. SureChill, a British-based maker of solar-powered fridges, offers a cheap pay-as-you-go plan for the use of its $800 fridges, as long as farmers prove that they will generate income from their use.

When it comes to keeping people cool with limited or no air-conditioning, building design is essential, particularly in dense cities. Nearly 60% of Africans will probably live in cities by the end of the decade. Around 70% of the buildings that are likely to exist on the continent by 2040 have yet to be built, according to the UN. That provides ample room for incorporating simple, cheap and sustainable building practices, such as building walls with mud brick or insulating them with charcoal, and making window shades from cheaper woods, such as eucalyptus. For existing houses, coating roofs in reflective white paint can reduce indoor temperatures and also cool the urban environment, as long as buildings are painted in clusters.

Governments will need to help scale up sustainable practices. They must abolish rules that prevent people from accessing cooling, such as high import tariffs on fridges. Designing regulation that favours greener appliances and improving labelling will help consumers choose more efficient options. Tighter building standards, heat-adaptation plans and more greenery for cities could cool the urban environment. The harder governments try, the more Africans will have access to some cool comfort as the planet warms.