There is loss, around 10%. One way to reduce it is to pre-heat the car while charging. Heat pumps in EVs are efficient/fast, and less annoying than waiting forever for a gas car to defrost.
There is also the additional friction from winter tires, and in summer drag from a bike rack. A bit similar to gas consumption, but does require planning stops on long trips.
Had a model 3 for 4 years, have another EV now.
It really depends on the type of driving.
Sure, if you are making a long road trip at high speeds then its probably negligible though still noticeable.
But being in Northeast US with constant traffic..
I used to have to park outdoors so the car would get cold soaked down to 20F in winter, and never really have sufficient time to warm up unless I was going for a 1hr+ drive.
Winter driving local roads, below-25mph stop&go, 2-5mi trips running errands..
Could see some really crazy consumption numbers pop up like 500-800Wh/mi+ versus the rated 250Wh/mi. Now it doesn't necessarily amount to much because it's on short single-digit mile trips, but it does happen. This stacks with the general cold weather efficiency losses of EVs..
If you burn gasoline in an ICE car only about 30% of the energy of that gasoline ends up actually going to propelling your vehicle. The rest is mostly lost as waste heat.
Burn it in a combined cycle power plant to convert it to electricity and there are still substantial loses to waste heat but much less than when burning it an ICE car. There will be some smaller losses in the power grid and charging infrastructure to get that electricity into your battery, and some small losses in your EV's electric powertrain, but in the end around 40% of the energy of the fuel ends up going toward propelling your vehicle.
18Mpg becomes 10Mpg or worse in the winter in my experience. EV driving can be more efficient if you don't let your battery cold soak for hours, or equally inefficient if you do leave your car unplugged overnight.
You’re ignoring conversion/storage losses when charging, which are on the order of 20%. And I think actual EVs are much closer to the less efficient end of your range (with the heat on, I barely get 3 miles / kWh on my Bolt, with no environmental controls, it’s about 4 miles / kWh, which is already the least efficient end of your range).
The energy density of the fuel isn't an apples-to-apples comparison. The chemical energy stored in gas is much harder to use. ICE cars typically get around 20-40% efficiency. Electric motors typically get 80-90%.
In some sense, they do that by moving the losses to before the battery/tank; so this isn't as big of a gain in terms of total energy usage. However, in terms of the effective capacity of the energy storage device, we don't really care about losses in refilling it.
That's true, but it does ignore the waste heat, which in winter months is used to warm the passenger compartment. It's one thing EVs do have working against them, though it doesn't make up for the huge efficiency gain EVs have overall.
To my knowledge EV chargers are close to 90% efficient from wall to tire. So about 5% loss going to the battery and 5% loss going from battery to drive the tires. This should get a little bit better as higher voltage harnesses appear in EV's.
But combustion engines operate somewhere around 50% efficiency? (i dont remember exactly, but I remember it being pretty bad). So the 10-20% lost through the road and the (presumably) small amount lost through electric, battery-less cars may actually be less overall than from combustion engines.
I am assuming that electric engines dont generate much heat if they dont have batteries and assuming that roads dont have the power on unless theres a car nearby.
Conditioning the battery isn’t a year round thing 20% more energy for 2 months a year is 1.7% efficiency loss across the full year. It’s also zero in a heated garage.
But again, as soon as you move up the chain on one car you need to move up the chain on the other or you’ll get as distorted picture of the tradeoffs.
Grid losses are a few percent with modern tech (which exists in countries rich enough for EVs). Charger losses are another few percent. If you were to burn the same fuel in a closed cycle turbine you'd get about 1.5x the raw energy to the wheels after losses, but the turbine also doesn't need to use as high emissions fossil fuels. Regen and other efficiency features that are tolerated on EVs but not ICEs bring it up to about double well to wheel.
Then you can also provide 50-90% of the energy without it ever being made into AC by parking it under $1000 worth of solar panels.
Few - Many electric cars use inefficient electric heat that draws as much battery power as the traction motors. Some have more efficient heat pumps, but not all. Regardless, heat is no more instant in an EV than a conventional vehicle.
> Does the energy you put into the system just go puff?
Yes, actually. The most common example of this is drivetrain power loss, which EVs are not immune to. Tesla engineers have stated that they are ~15% which is about the same as with ICE vehicles.
Internal combustion engines throw off heat whether you want them to or not, plus the total amount of energy stored in a gas tank is vastly greater than a battery, so wasting some of it as heat is less likely to strand you. EVs only get similar range by being much more efficient, and efficiency means less energy lost to heat.
EVs (and heat pumps) do not require renewable grids to be more efficient than ICE cars (and gas boilers)
They are sufficiently more efficient (roughly 4x) than even adding the 60% inefficiency of gas turbines and electricity transmission, charging losses etc. do not destroy their inherent efficiency advantage.
I agree with your point, though I guess its probably more like 2x the cars.
Also, in colder countries / states, the equation doesn't look as rosy. In winter, you use the heat generated by the combustion engine. Hence, efficiency goes way up.
Without knowing any numbers, I would assume, that at the moment, an additional, fossil fuel based, heating system would do the best job for an electric car. Webasto [1] for instance sells those.
There is also the additional friction from winter tires, and in summer drag from a bike rack. A bit similar to gas consumption, but does require planning stops on long trips.
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