Electric car heaters ??

[BADGER.BRAD]

Hello All,

Just a thought which has cropped up in my otherwise unused brain! Does anyone know how they heat an Electric car ? The only thing I could think of was excess heat from the motor/motors but cannot imagine there to be a lot,electrical heating would surely take way too much current so how is it done?

 

[Night Train]

There is insufficient heat from the motor or controller to heat he cabin, the heat developed is very low grade.

With DIY conversions the usual route is to use the heating element from a ceramic heater to replace the car's heater matrix. The ceramic heater is self regulating and so inherently safer in a car as it will not over heat is the fan fails.

I know of a chap in Ireland who has been experimenting with a dishwasher heater, the type that heats the water as it flows through a pipe, and is using that to heat a small amount of water that is then pumped around the existing heater matrix. It saved dismanteling the dash to get the matrix out.

Some, who live in very cold climates opt for diesel powered heaters like those made by Eberspacher and Webasto and used in truck cabs.
The Citroen Berlingo Electrique uses a similar heater adn so carrys a small diesel tank.

For my electric trike I am planning on the ceramic heater route, powered by the traction pack. I am watching a 110V industrial one on Ebay as my pack will be 96V.

This is where the pack size makes a difference. The heater isn't powered by the 12v accessory battery but by 96V, 144V, 156V, 204V, etc.

 

[krushavik]

On the morning show BBC 1 there's one of the team set off this morning in an electric mini. He's trying to go from London to Edinbrugh in a week, as the average mileage per charge is about 110. The place he got it from was explaining all about the vehicle and the one thing he did say is that it has a heater but it can only be used just to warm the vehicle and the he must turn it off as this uses 15% of the battery, and will then average about 75 mlies. When he set off he was full of intrepidation. I thought what happens when he gets in one of those two mile or so hold ups. What a waste of time. Expensive vehicle just to go shoppong.

 

[TheDoctor]

Well, I don't actually do many trips as long as 110 miles. I suspect most people don't.
And the hold up thing is not an issue - you stop moving and the motor draws no current. It's not idling like a petrol engine.
It's actually obvious if you think about it...

 

[krushavik]

Well, I don't actually do many trips as long as 110 miles. I suspect most people don't.
And the hold up thing is not an issue - you stop moving and the motor draws no current. It's not idling like a petrol engine.
It's actually obvious if you think about it...

Derr I fink ur right.

 

[Night Train]

Also it uses no energy if the car is coasting with the driver's foot off the pedal. Because there is no compression, as there is in an ICE, there is next to no resistance and so the car can coast for miles using no energy.

 

[TheDoctor]

Good point, NT. Try that with a ICE and you're still using fuel to keep the engine ticking over.
Unless you turn it off and lose the power brakes and steering...

 

[BADGER.BRAD]

Thanks for the info everyone,The truck night heaters are superb ( I used to be a Trucker) and very fuel efficient. I can remember a couple of New age Traveller friends who used them for winter Heating to great affect, I must admit though I found it very difficult to sleep with one running preferring my Arctic sleeping bag ( they sound like a small jet fighter), not of course a problem for this application. I don't use my car ( haven't got one at the moment) for many local journeys I tend to use my push bike for local and my Little 100cc motorbike for a bit further afield, the car is saved for longer family trips mainly in the summer so an electric car would not be a lot of use to me. But I have been on the look out for another matching motorbike just for the engine to replace the one I have (after a rebuild)This would then leave me with an ideal project bike for an electric conversion ( If that ever happens) A small electric Motorbike would be of Great use/interest to me but at present no one seems to make one ,plenty of scooter but no bikes.

What are your plans/uses for the Trike then Night train ?

 

[Night Train]

My plans for the trike are a little like the plans I had for the tractor, fun mainly. I am hoping I can afford to get the batteries to do mmy 70 mile round trip commute.

Here's the tractor.

 

[BADGER.BRAD]

I heard this mentioned the other day ( I think on radios 4's Home planet ,poss ???) That a modern cars electronic engine management system can tell if you are coasting in gear/on the over run ( if that makes sense) and turns the fuel off but if you knock it out of gear and coast you actually use more as the engine senses this and has to provide fuel for it to tick over. I used to know a few people who would knock the car out of gear and coast to save fuel in times gone by but this is now not the best thing to do, fuel wise anyway. I have tried coasting ,just to see how far you can go ( mainly to entertain my lad) and I must say it's supprising how far you can go without drive 2.1 miles is the best I've done down the side of a Welsh Mountain, and boy did I get some speed up.

ps I know your not supposed to coast out of gear

 

[Night Train]

Yes, that is true.

I am currently trying out my car for coasting out of gear and leaving it in gear. Currently leaving it in gear has the slight edge but it depends on the length of the hill and how much potential energy you can tap at the top of it.

I can run a mile or so out of gear a few times on my morning commute and can even use the very gentle slopes but if I leave it in gear I have to drive it down some of the gentle slopes to stop it slowing down too much and that uses fuel.

The best I have managed on my commute is 84mpg but that included switching off the engine sometimes.

 

[TheDoctor]

84 mpg!!! That's quite impressive! Are you driving a diesel Citroen, IIRC?
The best I ever, ever got was about 70 mpg going to Wales and back in a 1000 cc Fiat Uno.
I thought the fuel gauge was broken, as it was still reading full at Shrewsbury.

 

[zacklaws]

Don't worry about not having a heater, you'll soon get warm when you have to start pushing it.

 

[BADGER.BRAD]

It's always a bit of a dilemma whether to roll out of gear or in gear as you say some times if you do it in gear you end up having to drive it anyway ( very annoying when someone gets in the way of your economic driving a forces you to slow down!) The best car I had for fuel was a none turbo escort diesel (I've had 3 of them) All did 50/60 round town but always returned 75ish on a run the forth escort Diesel I had (It died on new years day) was a Turbo model and only did 40/45 round town and a max of 60 on a run.
A friend of mine had a Citroen ax 1.4 diesel and on our was back from Devon he decided to prove a point by driving all the way home at 56mph sticking with the trucks very nearly 90 mpg He got !

 

[Night Train]

84 mpg!!! That's quite impressive! Are you driving a diesel Citroen, IIRC?
The best I ever, ever got was about 70 mpg going to Wales and back in a 1000 cc Fiat Uno.
I thought the fuel gauge was broken, as it was still reading full at Shrewsbury.

I have a Skoda Ovtavia 1.9tdi Estate. I usualy average in the 60mpg range.

Don't worry about not having a heater, you'll soon get warm when you have to start pushing it.

You don't think much of EVs do you?

How about this one?
[media]
]View: http://www.youtube.com/watch?v=WyMhO5nGj2M[/media]