where does the heat come from in electric cars?

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where does the heat come from in electric cars?

"Cheap" EV cars have an electric resistance heater that hammers battery range. Those with air-con will (or should) run the system backwards so the element in the cabin becomes the condenser (heater).That gives heat at least 2x as efficiently of a simple resistance load. In very cold weather .they will all use resistance heating.


They also have heated seats as these use less energy than a full air heating system.
 
Expensive cars.. like tesla use resistance heaters, heat pumps (aircon in reverse) are more efficient until the temperatures drop, the colder they get the less efficient they become, also wherever they puMp the heat too like the evaporator in a normal aircon system can get too cold and freeze up. So the most reliable why to heat an electric car is in essence a 3 bar heater.

Other cars do use heat pumps, I think the older leaf did, but it wasn’t very reliable or consistent in very cold weather.

Batteries need to be kept warm to get the most out of them. The electric motors do generate some heat which can be fed into heating batteries, but it’s not enough for the cabin
 
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Please explain.?

My understanding is that the batteries under the rear seat have their own aircon

( they are more temperature dependant than the occupants..)

This latent heat could be harnessed.

The batteries are liquid cooled (and probably warmed when needed) with their own small radiator. Some might have heated windscreens to reduce hot air demand for demisting. Personally, I think all cars should be required to have heated screens as misting is often a problem with cold engines.
 
The batteries are liquid cooled (and probably warmed when needed) with their own small radiator. Some might have heated windscreens to reduce hot air demand for demisting. Personally, I think all cars should be required to have heated screens as misting is often a problem with cold engines.

its the side windows i always see steamed up as they pull out in front of me
 
its the side windows i always see steamed up as they pull out in front of me

Try driving a diesel Galaxy or VW Sharan from cold on a wet morning. If here is no heated screen you will wait hours for the engine to warm enough to make the car safe to drive. The windscreen mists as soon as you get in and its too far away to wipe while driving (which is of course illegal).
 
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Both the galaxy and sharan were fitted with a engine block heater on diesel models and some had a secondary heater in the back rear quarter fed by engine coolant. So it shouldn’t take “hours” to clear the windscreen.
 
I feel as though this is one of those issues that will be forgotten with time.

Cars "architecture" is designed in such way as to use what was abundant waste heat from the drive train. As time goes on we'll probably find they get better insulated and don't rely on blowing air about as much.

You can already set your electric car to demist/defrost while plugged into the mains from your bed (certainly offered on the Leaf via Carwings and the E-Golf)...I'd suggest those driving round with a foggy car haven't bothered.

That and the stuck in snow argument doesn't hold much water either..if you follow official advice you can idle your engine for 15 mins an hour to heat the vehicle anything more risks Carbon monoxide build up. 15 mins idling is going to generate precious little heat.

Don't doubt you could run the heater on an immobile electric car for 15 mins an hour for a reasonable amount of time given you won't be using energy for motive power.
 
This topic could get really complicated but my first thoughts are... what are the likes of Volvo, Saab (if the still exist) for northern Europe and contenders in the for North Canada/Alaska doing? These guys clearly have a more urgent/pressing need not only for weather challenges but they tend to be a little "greener" than the rest of the world.

Now for some fun stuff. So I hear/read (have not researched) that these EV vehicles have "technology" (water jackets, battery aircon, other tricks) up their sleeves to maximise battery life etc. plus other "tricks".

Now I guess many of us were thinking that compared to modern diesel engines a battery and electric motor has to be more reliable? I know the Peugot give an 8 year warranty on their EV batteries but what about all the surrounding tech? Heat pumps, coolers, chillers, heaters, regenerative brake and all those pesky CPUs that control these systems.

I think that in reality we are really looking at a vehicle market life of no more than 8 to 10 years and pretty much a net zero scrap value.

Motoring is going to become a completely new world, market and mind set.

I see Fiat have recently launched their hybrid 500 and Panda range. A good starting point in terms of vehicle size and expected use etc. I need to read up in more detail on the technical / warranty side.

Meanwhile with the ban on combustion vehicles rapidly approaching (just over 10 years for UK) will motor companies now push forward or hold back on hybrids and concentrate on maximising their combustion vehicle income whilst holding back on EV (but investing in EV R&D) so they can hit the ground in 10 years time with the latest and most reliable technology thus avoiding getting caught up in the changeover period where they are potentially vulnerable to all sorts of issues?
 
You can already set your electric car to demist/defrost while plugged into the mains from your bed (certainly offered on the Leaf via Carwings and the E-Golf)...I'd suggest those driving round with a foggy car haven't bothered.

lots of people don't have the luxury of being able to park their car near enough to their home to plug it in.
 
This topic could get really complicated but my first thoughts are... what are the likes of Volvo, Saab (if the still exist) for northern Europe and contenders in the for North Canada/Alaska doing? These guys clearly have a more urgent/pressing need not only for weather challenges but they tend to be a little "greener" than the rest of the world.

other countries don't have hundreds of cars stuck on a motorway if it snows, that's a uk problem
 
other countries don't have hundreds of cars stuck on a motorway if it snows, that's a uk problem

When snow is forecast in USA (and Canada), they close the roads. The "plows" go out in force and the snow is shoved on the side walks. But their weather is more predictable so it's worth having the permanent systems needed to keep the roads clear.

UK has such unpredictable weather we never know when or if it's going to snow.
 
Electric car charging will be a serious problem if we allow the likes of Ionity to take the micky on costs. They recently went to a subscription system that charges non members about £0.60 a unit.

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Frequent drivers in the transit tariff (17.95 euros per month) receive a preferential price of 0.31 euros per kWh at ionity columns. Customers in the city tariff (4.95 Euro per month) must continue to pay the full price of 0.79 Euro per kWh at Ionity.

They have installation costs and electricity costs but considering domestic power will cost about 12p per kWh that's a serious margin they are expecting people to pay.

On the other hand free to use chargers are silly in the other direction. The equipment and power lines have to be installed and maintained.
 
Later cars had the Eberspacher diesel powered heater but reliability was not a feature they were renowned for. My top spec (six captain seat) Mk1 Sharan 1.9 had no block heater.
 
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