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How does this heat waste (heat production) compare to people's heat waste from heating your home, heating water in your home, etc.? (Take Toronto, or some other city, typical driving distance, given outdoor climate etc.) Just a round figure: is it 1-5-10-20-30% of people's average heat emission?

Like cars, it depends on the source of energy. Fossil fuel heating (eg natural gas) create heat from chemicals. But electric heat pumps don’t. They move heat energy around like a reversible refrigerator. One is literally burning something for energy while the other is moving existing energy around.

The problem with worrying about waste heat is it is so insignificant compared to captured solar energy from greenhouse gases. We’ve got 12 nuclear bombs a second of ocean warming from a small amount of CO2, and people are shutting down green nuclear in France for heating a river w/ fish. Priorities!

Yeah, as much as I love Streetsblog and as much as I hate cars of all kinds, the direct heating effect of combustion is a sideshow at best, compared to the greenhouse consequences and even compared to direct heating of road surfaces by sunlight.

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.

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.

Admitting an AI analysis: Gas compared to EV over 100km. Total Heat Released to Atmosphere Gas ~235.0 MJ EV ~65.0 MJ This includes power production and transportation of energy. For those who charge using renewables only: EV ~19 MJ Sound plausible?

After being distracted, busy, and struggling to find reliable sources, I finally finished my analysis: Per 100km, total heat released from driving: Average gas vehicle: 462.52 MJ Average EV (3.6 mi/kWh): 101.39 MJ An EV charged exclusively with renewables: 72.42 MJ

I want to put together a coherent document on how I calculated this, such as the 20-45% discrepancy between how the EU advertises fuel efficiency and real-world data, and how it's difficult to find efficiency of an EV expressed as a true system efficiency instead of relative to the battery size.

AI has several problems when it comes to estimating things to do with vehicle efficiency. For example, it tries to use mpg directly when calculating averages which introduces errors. The greater the difference, the greater the error. Here's an explanation of why: youtu.be/oLQmwOX6Xds

The MJs AI spit out is heat lost per 100km. Thus 2.3 per km for gas which is smaller than the 3.9 originally posted. Of course the numbers will change based on driving habits and efficiency of a particular vehicle. More interesting are the differences in the percentages between the ICE and the EV.

It tends to radically overestimate small values and underestimate larger values, which throws off such calculations. I am currently looking up information to make sure I do an accurate calculation and then I will reply with that.