Making the case for AC, with conditions attached

Britain is living through the third heatwave of this year, with the temperatures set to top 35 degrees again this weekend. It’s tempting to picture that as sunhats, ice cream and sandy beaches, the image the media often reaches for. But Climate Outreach has built a photo library showing the reality of extreme heat, and is reflected in new polling published by the End Fuel Poverty Coalition yesterday.

Over 15 million adults (a quarter of UK adults) felt unwell in June’s hot spell, including nearly half of people in financial difficulty and 44 per cent of disabled people. The same heat dome caused an estimated 20,000 deaths across Europe, 862 of them here in the UK. One in six babies in England live in homes that tend to overheat.

Britain isn’t ready for this new reality. Last year Green Alliance produced Adapt to thrive, a major report for our Adaptation Task Force, which found that two thirds of government action on the UK’s biggest climate risks was inadequate.

Why passive cooling has limits
A ‘passive cooling first’ approach, using insulation, shutters, shading and ventilation, before mechanical measures, should be the starting point. They are cheap, efficient and good for bills all year round. However, in many older homes, insulation essentially acts like a blanket: it is great at keeping heat in or out in the first place, but hopeless once heat is already trapped inside. Efforts to improve insulation need to be paired with proper ventilation so building users can expel heat more easily and prevent damp developing.

There is a scale challenge here. Building rules only began to address preventing overheating for new homes in 2021. Most of the UK’s building stock is older and the Climate Change Committee (CCC) now expects 92 per cent of existing homes to be at risk of overheating by the middle of the century. The government has made good ground in committing to build passive cooling into retrofit schemes for low income households, but this should extend to all retrofit work, and actually reach the people who really need it most.

The risks fall hardest on people with the least power to change their environment. Nearly half of the poorest fifth of English households live in homes prone to overheating, three times the rate of the richest fifth, and renters – who can’t make structural property changes – and people from ethnic minority backgrounds are more exposed too due to the areas of cities where they live. The guidance is that newborns should be kept below 20 degrees, which is nearly impossible to meet in much UK housing, and young children generally are disproportionately affected, as they are less able to regulate their body heat. Disabled people suffered during the last heatwave too, with over half of those polled losing sleep because their homes were too hot, and close to one in five couldn’t afford to cool their homes down.

The UK can’t insulate its way out of the problem
The government needs to do more, and urgently, to prepare people to cope better with more regular instances of extreme heat. Providing active cooling, like air conditioning, will be vital for some: especially those with health issues, low income households and those with young children struggling to keep cool. It’s the only way to achieve a safe temperature for some. Cost, energy use and access to the technology are concerns, but should all be considerations in planning support programmes.

Air conditioning should be installed simultaneously with the rollout of solar power to schools, hospitals and care homes, starting with the people who need it most. This makes sense, as cooling demand will peak exactly when solar power generation does, making an everyday benefit of decarbonising the grid directly apparent. If it lets people sleep well through a hot summer night, noticeably making their lives better, not just less bad, it might turn out to be popular politically too.

Reversible air to air heat pumps do this, cooling homes in summer and heating them in winter. The good news is that they now qualify for support through the boiler upgrade scheme. Yet, take up so far has been extremely low, exposing a failure by the government to communicate the scheme and its benefits. Few people also know that active cooling works best when installed after passive cooling measures: a hospital with a white roof for instance, or better still a green one, needs less air conditioning than one with a dark roof.

Baroness Brown, chair of the CCC’s Adaptation Committee, said in 2023 that successive governments have presided over a “lost decade” on adaption. The next National Adaptation Programme isn’t released until 2028. After three heatwaves in three months, people simply can’t wait that long for more to be done.

 

Green Alliance’s Adaptation Task Force aims to inspire a step change in UK government climate adaptation and resilience policy. Current members include AVIVA, ISEP, National Trust, OVO Energy, SSE, Wessex Water and Zurich. Companies interested in joining should contact Green Alliance’s head of research, Liam Hardy lhardy@green-alliance.org.uk.

Image credit: Alastair Johnstone / Climate Visuals