Cool roofs could have saved hundreds in London heatwave - study

2018 saw London experience its hottest ever June-August period, with the average temperature of 19.2°C being 1.6°C higher than usual. The new research, conducted by UCL and Exeter University, found that had ‘high-albedo’ cool roofs (roofs painted white or with a reflective coating) been widely installed throughout the capital, it could have cooled the city by about 0.8°C on average. That reduction could have saved the lives of an estimated 249 people – around 32 per cent of the heat-related deaths during that period.

The team also studied the effect that rooftop photovoltaics (RPV) could have had on London temperatures. It was found that wide adoption of rooftop solar would have cooled the city by about 0.3°C, saving an estimated 96 lives. RPV would also have generated as much as 20TWh of electricity during the three-month period, which is more than half of London’s total electricity usage for 2018. The research is published in Nature Cities.