where does the heat come from in electric cars?

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where does the heat come from in electric cars?

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Personally, I think all cars should be required to have heated screens as misting is often a problem with cold engines.

Ford are credited with creating the heated screen, and initially they were very expensive as only 1 in 3 from production were fit to use.

Now most Ford cars have them as standard, but typical Ford, they are made poorly. They work well, very well, the ice and snow just melts off before you've scraped the front side windows. I had heated screens with the AA Driving School Fiestas for 8 years, but despite the benefit on cold mornings, would prefer not to have them.

On all the heated screens I have seen, not just Ford, the heating wires are visible. Very visible on Fords, often difficult to see, but still there on others. All the time with the Fords, you are squinting through these lines, makes a nonsense of keeping a clean windscreen when they have obstructions built in. When the sun drops in the sky, they become worse.

Then in the dark, every oncoming car will highlight the wires, glinting at you, reducing the visibility. Far worse in the Fords than in other makes.

I was glad to say goodbye. No heated screen in the Fabia, and does not take long to put warm air up for demist.
 
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My sons Focus tdci had it..
It was like having 'chicken wire' instead of glass

Although probably useful in a diesel.. as you can do half of a winters journey before any meaningful heat arrives through the vents
 

MaxHeadroom

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A friend had a Ford Escort Convvertible XR3i - or at least thats what I think it was. It too had a heated windscreen and as has been pointed out they were very expensive.

One morning he went out to his car and found some scumbag had stolen the windscreen!
However they failed to notice the expensive leather jacket on the back seat with a well-stuffed wallet in one of the pockets :eek:

Until someone pointed out the wires in the windscreen, I never noticed them, but after that I couldnt stop myself trying to focus on them rather than the road ahead! (n)

Aircraft have heated windscreens that get really hot - but there are no wires - instead the screen has a thin, transparent, conductive film over the surface to which a voltage is applied which evenly distributes heat over the entire panel. The window film is usually a Indium tin oxide, or gold - far better than a windscreen full of wiggly wires!

This design probably isn't used on everyday cars due to cost.
 

chris3234

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A friend had a Ford Escort Convvertible XR3i - or at least thats what I think it was. It too had a heated windscreen and as has been pointed out they were very expensive.

One morning he went out to his car and found some scumbag had stolen the windscreen!
However they failed to notice the expensive leather jacket on the back seat with a well-stuffed wallet in one of the pockets :eek:

Until someone pointed out the wires in the windscreen, I never noticed them, but after that I couldnt stop myself trying to focus on them rather than the road ahead! (n)

Aircraft have heated windscreens that get really hot - but there are no wires - instead the screen has a thin, transparent, conductive film over the surface to which a voltage is applied which evenly distributes heat over the entire panel. The window film is usually a Indium tin oxide, or gold - far better than a windscreen full of wiggly wires!

This design probably isn't used on everyday cars due to cost.
The aircraft ones probably just massive amounts of power as well as the fact there has been a lot of issue's caused by them on aircraft over the years
I'm betting something like 2-4kw those system run at will take a lot of heat flying at 500mph and 38k feet

I doubt they run at car voltages either probably 100v+
 
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AndyRKett

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This design probably isn't used on everyday cars due to cost.

That and most cars probably don’t really have to worry about the massively low temperatures that planes experience at 40,000 feet.

I’m sure the aircraft set up is much better than the wiggle wires of your average Ford Focus lol
 

StevenRB45

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No heated screen in the Fabia, and does not take long to put warm air up for demist.

Modern emissions standards favour cars that heat up quickly so you tend to find the small turbo petrols do.

It's been a while since I've looked but if I remember right you were allowed a "thermal window" of time during cold running where emissions can be higher to stop catalyst damage.

Many diesels took the mick on this as part of dieselgate, it was effectively the legal version of what VW did. As a result it got a lot more tightly controlled. The original intention of the thermal window was to protect emissions gear in cold running...one manufacturer had set it to classify 17 Celsius as cold running, so in the UK that car would have no emissions controls 11 months of the year.:eek:
 
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DaveMcT

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The Konisegg Freevalve engine created for general production (but ignored by the industry) was set so that one exhaust valve fed the turbo and the other bypassed it. No waste gate needed. On cold start the ignition is retarded and turbo is given no exhaust gas. The delayed spark throws flames down the exhaust which rapidly heat the catalyst.
The valves are all under electronic control with solenoids controlling the valves. There is no mechanical camshaft saving considerable weight and cost.
The engine efficiency make diesels unnecessary and manufacturing costs are considerably less. Who knows why the car makers have ignored them.
 

chris3234

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The Konisegg Freevalve engine created for general production (but ignored by the industry) was set so that one exhaust valve fed the turbo and the other bypassed it. No waste gate needed. On cold start the ignition is retarded and turbo is given no exhaust gas. The delayed spark throws flames down the exhaust which rapidly heat the catalyst.
The valves are all under electronic control with solenoids controlling the valves. There is no mechanical camshaft saving considerable weight and cost.
The engine efficiency make diesels unnecessary and manufacturing costs are considerably less. Who knows why the car makers have ignored them.
cost and reliability almost certainly
I'd it was as good as it's supposed to be and they could make it work they would I'm sure
 

DaveMcT

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cost and reliability almost certainly
I'd it was as good as it's supposed to be and they could make it work they would I'm sure

The whole point was considerably lower cost. It uses normal valves but removes the belt, cams, tappets, etc. and add many other benefits. I suspect the real problem is what will ultimately kill Big Auto. They don't like change so stuff gets ignored until it's too late.
 
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