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Cars are one of the reasons why cities get so much hotter. An average gasoline car can produce 3.9 MJ of waste heat for *every kilometre* it drives. That’s enough to raise the temperature of a 665 sqft apartment twenty degrees centigrade.

mass.streetsblog.orgExhaust Pipes Are Making Heat Waves Much, Much Worse - Streetsblog MassachusettsThe long-term climate impacts of the climate pollution from cars and trucks are well documented, but the daily short-term effects of the wasted heat energy radiating from engine blocks and exhaust pip...

The reason why this happens is because gasoline is literally concentrated chemical energy. And a gas engine literally ignites that fuel to produce heat and pressure in order to turn the pistons that create thrust.

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Even the best gas car is very inefficient at converting the chemical energy in gasoline into useful energy. Nearly all fossil fuel engines use less than 50% of the energy stored in gasoline into actual useful stuff. The rest is waste heat. (It’s why all gas cars have heaters but not cooling)

In comparison, electric vehicles run at about 90-95% efficiency. So they will produce far less direct heating to the environment around them. That doesn’t solve, however, the problem with pavement, stores heat energy and can be 20-25º centigrade hotter than the air temperature around it.

Notable: coal, oil, natural gas, and nuclear all produce significant excess heat. Each of these use stored energy to boil water in order to create steam to turn a turbine. Thats heat. Hydro and wind turn turbines without steam. And solar converts sunlight directly to electricity.

A radically efficient vehicle engine is 40% efficient. The most efficient vehicle engine is barely over 51% efficient. There's like only one engine that does that. The rest of the niche of peak efficiency engines are still barely above 40%.