By Geraldine Herbert

Copyright independent

A new study from Lisbon has found that black cars actually make the streets around them hotter. Dark paint absorbs sunlight while light paint reflects it. And it’s not just black, common colours like grey and blue are also on the warmer side. Unlike thick asphalt, a car’s metallic body heats fast and releases that heat to nearby air much more rapidly, especially if painted black or dark gray.

Why is city heat becoming such a big issue?

Higher temperatures mean more people suffering from heat exhaustion and sleepless nights, especially the elderly or anyone with health problems. Air conditioners have to work harder, pushing up energy bills and straining power grids. The extra heat also creates more smog and ozone, making the air harder to breathe. Even trees and parks struggle in prolonged heat.

How much hotter does it get near a dark-coloured car?

In Lisbon’s summer heat, the air just above a parked black car was nearly 3.8°C warmer than over nearby asphalt. A black SUV in full sun can turn into a mobile radiator, heating the air around it while white cars, in contrast, sometimes cooled their surroundings relative to the road.

What is the overall impact of this colour-generated heat?

In central Lisbon, with parked cars taking up about 10pc of total road surface and more than 700,000 vehicles passing through the city daily, black or dark-coloured cars make a significant contribution to what’s called the urban heat island effect. And unfortunately dark-coloured electric vehicles have exactly the same impact.

Should drivers avoid dark cars altogether?

If you live in a hot city and park outside, a lighter-coloured vehicle is the way to do your bit for the microclimate.

A black car may look sleek, but it’s also a rolling heat lamp. If comfort and climate are your priority, consider silver, white or even pale blue. Your passengers and your neighbours will thank you.