Electric car heaters ??

[User482]

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.

In fairness, modern engines turn off the fuel supply when on overrun. So when you coast to the lights in gear, you don't use any fuel. Electric cars usually have some kind of energy recovery system when coasting, so the frictional losses resulting mean that they will slow down at a similar rate to a conventional car.

 

[Night Train]

In fairness, modern engines turn off the fuel supply when on overrun. So when you coast to the lights in gear, you don't use any fuel. Electric cars usually have some kind of energy recovery system when coasting, so the frictional losses resulting mean that they will slow down at a similar rate to a conventional car.

Yes, this is true.
But both an ICE on compression over run and regen braking on an electric car shortens range.

On my commute home the last mile of the motorway, right up to the roundabout junction can be done in neutral coasting, but it costs me in diesel to stop the engine stalling. If I left it in gear I would have to drive the whole distance right up to the sliproad before I can come off the throttle.

If I had an electric car on the same bit of road the regen would be more of a hinderance then a help the regen would only return about 10% or so of the energy I would expend driving to the junction where as if I coasted I would save the other 90% as well.

In effect, a modern ICE would be better left in gear on drive and over run but an electric would be better without regen for the same journey.

 

[GrumpyGregry]

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 !

I had an atmo diesel escort as a company car that I inherited from my predecessor when I worked for a very frugal employer. fuel economy was it's only redeeming feature as I recall. 0 - 60 time about twice that of my current 900cc cinquecento.

 

[BADGER.BRAD]

Do you think any useful charge for the batteries could be obtained purely from the braking side rather than all the time the vehicle was rolling as such, I seem to remember hearing that some commercial vehicles did this as an aid to standard braking ( not sure what they did with the electricity created ! I presume it was just fed into some sort of heavy electrical loading) maybe this could be used as brakes rather than friction material. Not sure how this would work extra generators on the wheels replacing the brakes would add too much weight I would have thought and the inbuilt drive motor would most likely not be ideally suited to this application?

 

[Night Train]

Regen braking can be very effective in the same way the electric retarders were on lorries. Instead of the energy going to resistor dumps it is fed back into the battery pack. The big problem is that it is difficult to throw too much energy into the batteries too quickly and so, in cars at least, it is not as effective as it could be.

In reality, for most driving the return in regen is about 10% of the energy used during the drive. It is more useful if the driving was on very hilly roads and then the regen can be used as 'engine' braking to save the service brakes and it can then add considerably more to the battery pack due to prolonged braking.

It is possible to use the controller to emergency stop a vehicle by feeding energy to the motor backwards.
Forklift trucks do this as 'plug braking' and holding on slopes. I have the same set up on my tractor so when I come off the accelerator the tractor slows immediately rather then coasting.

 

[buggi]

they tested some electric cars for a year at my work over the last year (National Grid) and the two girls who had them wrote a blog. Basically, heating the car took so much energy that the range of the car depleted rapidly, so during the winter they used hot water bottles to keep themselves warm in order that they could get home!

There were good and bad points about the car. They liked the novelty but they thought that no engine noise caused a safety issue (worried pedestrians might step out as wildlife (birds etc) didn't even hear them coming most of the time, and the range was a bit of a problem. Ok for a run around but can't do long journeys. I think the car only averaged around 2/3 of the range that was stated and its a bugger if you forget to plug them in overnight LOL

I suppose tho, the range will improve over the next couple of years and before long you'll get electric cars that go on for miles. And they are going to do noises that you can download for the car (like the noise of a ferrari LOL) Personally, I wouldn't buy one just yet though because (a) they don't go far enough and (b) they are quite pricey at the moment.

 

[Night Train]

A typical diesel engine uses between a ½ and ¾ of a litre of fuel per hour while ticking over. So providing you are moving at over 10mph your in the money, freewheeling at 40mph is the equivalent of about 300mpg

Free wheeling does have its dangers, if your engine cuts out you could on many types of vehicles loose your brakes and steering.

It surprises me that we don't have cars with free-wheeling gears similar to what we have on bikes, ie. when the engine is not needed to drive the wheels the engine disconnects from the drive train and the momentum of the car is not compromised by having to spin a heavy engine.

My car computor reckons anywhere between 300 - over 900mpg when ticking over and coasting in neutral.

The engine management also works to prevent stalling so it is unlikely to cut out. The anti stall is so effective that It will pull the car up a reasonably steep hill from stand still with no application of the throttle pedal.
The loss of the engine shouldn't mean loss of steering and/or brakes, they just need more then finger tip pressure to operate just like cars before the 80's.

I think some car makers experimented in the past with a freewheel but it posed problems as there was no engine braking on hills and when selecting reverse gear the freewheel had to be locked.
There wasn't enough of a problem to solve to warrent continuing with a freewheel in the gearbox, especially given how 'cheap' oil based fuels were.


There is a benefit to having a freewheel between the motor and gearbox of a converted electric car in lieu of a flywheel and clutch though. It makes clutchless gear changes much easier and prevents 'over speeding to distruction' of the motor when the car is decending a hill.

The problem so far is that those of us doing the DIY development of electric cars can't find a suitable freewheel unit that can handle the torque and the speed and the misalignment inherant in automotive gearboxes while being smaller and lighter then the flywheel clutch assembly it would replace and still not cost many ££££s.

 

[Night Train]

they tested some electric cars for a year at my work over the last year (National Grid) and the two girls who had them wrote a blog. Basically, heating the car took so much energy that the range of the car depleted rapidly, so during the winter they used hot water bottles to keep themselves warm in order that they could get home!

There were good and bad points about the car. They liked the novelty but they thought that no engine noise caused a safety issue (worried pedestrians might step out as wildlife (birds etc) didn't even hear them coming most of the time, and the range was a bit of a problem. Ok for a run around but can't do long journeys. I think the car only averaged around 2/3 of the range that was stated and its a bugger if you forget to plug them in overnight LOL

I suppose tho, the range will improve over the next couple of years and before long you'll get electric cars that go on for miles. And they are going to do noises that you can download for the car (like the noise of a ferrari LOL) Personally, I wouldn't buy one just yet though because (a) they don't go far enough and (b) they are quite pricey at the moment.

Current electric cars tend to 'promote' their best range, in the same way that the MPG of a car is often better then can be found in realistic driving. Many factors have an effect, driving style, ambient temperature, auxillary loads (lights, heater, wipers, etc as required in winter) and so the range may not be as expected.
The range is also often the maximum range possible disregarding battery protection. Usually the range should be considered as 50% for lead acid batterys and 80% for the latest lithium batteries of the maximum possible.

The lack of noise is an issue of great debate. I am on the side that says 'the car isn't too quiet, the rest of the environment is too noisy!'. However, the EU is debating a noise element in the design but they are looking at some odd and disturbing whines raising in pitch dependent on the speed. they are very much aiming to avoid allowing 'downloadable' sounds along the lines of ring tones.
Personally I would like a steam engine 'chuff chuff' sound or an old slow reving diesel.

A friend of mine is currently building up a Citroen Berlingo Electrique with a range of 250+miles, that should be enougn for most people.
I only need 70 miles to be happy.

The price ought to come down but may not due to the almost exclusive Chinese hold on the world supplies of lithium (I must have a chat with my relatives).

However, another way to look at the cost is to compare the cost of the battery pack to the cost of the fuel used in an ICE car.

The battery pack in my trike will be 96V at 160ah giving a capacity of 15.36kWh. My electricity costs 12p per kWh so a full 70% charge (I will only need to use 70% capacity to get my 70 miles) will cost £1.29.
My trike will need £3500 of batteries and cost £1.29 a night to charge. I will get 70miles per charge. The batteries will last 1000 charge cycles.

Over the life of the batteries that is 70,000miles costing £1290 electricity and £3500 batteries.
That gives 70,000 miles costing £4790.

With my diesel car at, say, 50mpg and £6 gallon I will use 1400 gallons to do 70,000miles costing £8400.

That is a saving of £3610 which covers the cost of replacing the pack leading to even more saving for the next 70,000miles.

Now fuel cost will go up but electricity prices will not go up as much or as quickly as diesel prices will over those 70,000miles of driving.
Also the maintenance costs are considerably lower too.

 

[BADGER.BRAD]

Are these on board car computers anywhere near accurate now days ? I remember them being way out to reality some years ago. A friend of mine had a jag that would tell you it was doing 30mpg when in fact it was always nearer half of that if he was lucky very similar to another friend with a Merc.

 

[Night Train]

I think as an overall average it has been fine. I don't know how accurate it is when it is on 2 second update but it is a good guide, along side the trip average, to let me know if I am doing well or not.
Certainly, on a long motorway run, it seems to tally with the rate of refueling.

 

[Black Sheep]

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.

that mini is useless as a family car - the whole back seat and some of the boot is taken up with battery packs.
yes, the technology is in it, but at the expense of practicality.

they tested some electric cars for a year at my work over the last year (National Grid) and the two girls who had them wrote a blog. Basically, heating the car took so much energy that the range of the car depleted rapidly, so during the winter they used hot water bottles to keep themselves warm in order that they could get home!

There were good and bad points about the car. They liked the novelty but they thought that no engine noise caused a safety issue (worried pedestrians might step out as wildlife (birds etc) didn't even hear them coming most of the time, and the range was a bit of a problem. Ok for a run around but can't do long journeys. I think the car only averaged around 2/3 of the range that was stated and its a bugger if you forget to plug them in overnight LOL

I suppose tho, the range will improve over the next couple of years and before long you'll get electric cars that go on for miles. And they are going to do noises that you can download for the car (like the noise of a ferrari LOL) Personally, I wouldn't buy one just yet though because (a) they don't go far enough and (b) they are quite pricey at the moment.

if I remember rightly from my days of studdying transport design, the japanese have a minimum drive by noise that the car has to make in order to be legal

the EU has a maximum noise.


with regards to practicality, when a company makes an electric car that can take a family of five on a camping holiday then they've got it nailed - we're not there yet, and they're working on it which is great

but we also need to change how we own cars, just having them for 3 years and selling them onwards is not sustainable as electric cars produce more emissions to extract elements needed for production, produce parts, ship parts to assembly, assemble etc than a similar size internal combustion car

 

[BADGER.BRAD]

Just clocked my new banger a Citroen ZX 1.9 Turbo Diesel at 62.5mpg around town. I'm impressed! My last turbo Escort did 40mpg around town 60 on a run and what I previously thought was brilliant my 3 non turbo Escorts 50mpg town 75 on a run. I'll have to wait see what it is like on a run !

 

[Night Train]

but we also need to change how we own cars, just having them for 3 years and selling them onwards is not sustainable as electric cars produce more emissions to extract elements needed for production, produce parts, ship parts to assembly, assemble etc than a similar size internal combustion car

That argument would only make sense if the whole process of drilling for oil, refining it, shipping it and clearing up spills was also taken into account with ICE cars.
At least with batteries many of the elements that make them up can be recycled, unlike burnt fuel oils, and some if not all of the electricity could be generated by renewables.

There are pros and cons on both sides just as there would be if we examined returned to using horses and cattle as the main motive power for transport or relied only on human power with bicycles and sails on ships.

however the three year ownership is very bad. I always intend to run a vehicle to the point of total degradation and then recycle the remaining parts. Current car was bought new and is 10 years old now. It does mean I have to look after it better though but that is not a bad thing.