EVs and the heater on a cold morning !

[pgk pgkParticipant @pgkpgk17461]

A lot of myths to dispel here.
My Tesla S is over 3yrs old no and tech has moved on a little since.
This am remote app informed me cabin and outside temps 3C so I told it to warm up and put my seat heater on before bothering going out. Within 5 mins the cabin was 22C but battery heating would have taken a lot longer and I didn't want to wait.
For the shortish trip i was doing then in summer I'll average 300wh/m. Today it was 400wh/m while the cabin and seat heaters ran and the battery pack was warming up to ideal – which took about 10-12 miles. I was toasty warm.
First stop was only a few mins at screfix then start up again and go to two other stops both of which were a little longer and car had a chance to cool down (I could have told it to keep the heaters on but it was getting sunny)

For the last 30 miles of the 40mile total trip distance I averaged 340 wh/m – this was country A and B roads. I could possibly have done better on just A roads and probably much the same cruising at 65mph on a motorway (barring wind, hills etc). I could have done a heck of a lot worse if I’d been heavy-footing it and charging around. During 'playtime' summer runs I've managed to burn more than 450 wh/m but age brings wisdom and a wish to avoid other yahoos.

The latest generation of Teslas are more efficient.. heat pumps as stated and at one time they also used the drive motors to warm the car by alternating current through them. A model3 will run around 250-270 wh/m summer time.

If the main pack is either totally full or too cold then regen braking can't store energy and you have to use conventional brakes…but you do need to use them regularly anyway to prevent discs rusting and pitting.

If ya thinks about it a 2KW fan heater will keep an average-sized houseroom warm and while a car is less well insulated the cabin volume is tiny in comparison.. 0.5-1KW should keep it comfortable and in an hour you’ve gone 60 miles.

Were I to do a 280 mile round trip in mine then I'd set things up so it was fully charged and pre-heated before leaving. I wouldn't try to do it without a top-up at some stage even though it probably could if one drove carefully- there's no point risking running out of juice should there be a traffic jam or accident or have range anxiety but a pit-stop to add say 50 miles (call it 20kwh on my car in winter) range at an optimum battery state (ideally) would be less than 25 mins on an older fashioned 50KW charger or 10 mins on the newer ones – and I need to pee every couple of hours. In the future one can expect most destinations will have some sort of charger around – albeit 7kw A/C one's so if staying 3hrs then no need to stop en route.

The latest gen cars can take a DC charge in ideal conditions at 250KW from 20% to say 40% then it drops as the pack fills up and gets some balancing done but a model3 on a 3rd gen Tesla supercharger from 20%-80% battery pack is about 20 mins and adds 160+ miles range.

pgk

[duncan webster 1Participant @duncanwebster1]

When I had to leave home at 06:00 to get to work 90 miles away the morning drill was to put a fan heater in the car for 5 minutes whilst having breakfast. De-iced and nice and warm as long as you didn't turn the heater on for a few miles whist the engine warmed up. Had I been more organised I'd have fitted an external power hook up.

On the subject of sheepskins, we have a country where a lot of it will only grow grass, so we can produce sheep and wool, but we plough the wool into the fields as fertiliser (or to get rid of it) and use oil to produce man made fibres which eventually finish up in the rivers and seas as microplastics. The National Trust announced some time ago it was commissioning a study into how to replace the fleece jackets issued to staff. I would have thought the solution was obvious, but of course I don't get thousands of pounds a day as a consultant

[pgk pgkParticipant @pgkpgk17461]

Duncan,

If you every do get your consultancy please point out how many fields are used to grow sheep that would indeed be ideal for growing bushes and trees for fruit and nuts instead of importing the blessed things. I'm irritated by the need to import Christmas chestnuts from Spain, walnuts from California, hazelnuts from Turkey – all of which we can grow here. Indeed locally there are no sweet chestnut or walnut trees apart from the one’s I've put in and the climate in Wales is ideal for Monkey Puzzles which have large edible seeds and super timber

pgk

[Clive HartlandParticipant @clivehartland94829]

Channel 4 tonight 2030hrs. Your EV.

[V8EngParticipant @v8eng]

Posted by Clive Hartland on 22/11/2021 15:36:54:

Channel 4 tonight 2030hrs. Your EV.

Now set to record thanks.

[Robert Atkinson 2Participant @robertatkinson2]

PGK PGK hints at another issue, you can't charge the battery when it's very cold. They have to use mains power to warm up the "coolant" and cells before charging can start. Not too much of an issue in the UK or if charging straight after a run but is an issue in colder climates when using off-peak or sequenced charging.
No I'm not anti EV, I drive a plug-in hybrid. I'd consider a full EV but have nowhere to charge at home. Currently I charge at work which covers my commute.

Robert G8RPI.

[Howard LewisParticipant @howardlewis46836]

I am not anti EV, but the current state of play does not suit our lifestyle.

We consider a journey of less than 50 miles to be relatively short.

(B i L used to use an E class Mercedes for the weekly 1 mile each way shopping trip! )

In two days, we shall attend the funeral of S i L. This means a journey of 150 miles each way, and the crematorium is unlikely to have a charging point. None of the three of us would want to spend time hanging about a service area while the car recharges, (Because of the inactivity, wife scarcely tolerates such a journey, anyway)

So our little EV6 compliant puddle jumper will convey us, hopefully non stop, without the need for a refuelling stop. (And yes, I do wish that the fuel tank was a bit larger to give a 500 mile range. I have needed that! )

We are of an age where an EV with a range to suit our lifestyle, and budget, is not likely to be available to us

One of the choices that we all have to make in life.

Howard.

.

[Andrew CattellParticipant @andrewcattell93655]

I understand the technology limitations regarding not being able to use regen braking if the battery is full but………

how can the battery be full once the car has disconnected from charging and got up to speed? Unless you start from a point of significant altitude and drive down hill the energy from regen will be less than you used getting up to the speed at the start of braking. The recoverable energy will be less than than that used getting going until perpetual motion machines get perfected, and that won't be any time soon!

Andrew

[not done it yetParticipant @notdoneityet]

Posted by Andrew Cattell on 23/11/2021 19:44:15:

I understand the technology limitations regarding not being able to use regen braking if the battery is full but………

how can the battery be full once the car has disconnected from charging and got up to speed? Unless you start from a point of significant altitude and drive down hill the energy from regen will be less than you used getting up to the speed at the start of braking. The recoverable energy will be less than than that used getting going until perpetual motion machines get perfected, and that won't be any time soon!

Andrew

That is easy enough to explain. No chemical battery charges at full rate as it nears full charge. OK, lead acid can be overcharged to equalise cells, but Lithium chemistry is most definitely not like that.

A cold battery, likewise cannot be charged close to full charge at a high rate. One can usually brake much more heavily than that current used to accelerate to that speed – and sometimes need to! So it is the regenerative charging rate that has to be reduced to protect the cells from possible over-voltage.

For longevity, EV batteries are better charged and discharged between 20% and 80%. Most, who lease a vehicle for only 2 or 3 years could not care a jot about battery longevity – even if they actually thought about it. They don’t get any benefit from so doing!

[Max ToleranceParticipant @maxtolerance69251]

I got my first fully electric car in May this year. It has a 64Kw battery pack which it is claimed will give me around 300 miles range. However, because i use regen on braking and because I am not interested in "performance" driving I exceed the figures by about 10 percent. I reckon in summer to get around 330 miles range in general motoring around town. I do use the car on motorways occasionally and have done the trip from east Lancashire to Hull the full round trip a number of times without having to recharge en-route. I can't remember the exact mileage ( it will have been around 130- 140 miles each way) and I still had 45 miles range when I got home. So, even at motorway speeds I reckon the mileage is pretty much the same. One thing that isn't generally realised is that when travelling down hill the car uses very little power from the battery. In fact on my daily commute of around ten miles to work, most of the way there is actually up hill and the range will drop by about 18 miles, Even though the oddometer recordsonly ten miles travelled. However on the way home I actually end up with more miles on the range than when I set off. Simply because the regen braking puts more juice back into the battery than I am actually using.

Now it is winter the range is a bit less probably around 280-290 miles on a full charge. BUT i have the lights etc. on plus the heating (set at 22 degrees) plus the heated steering wheel and drivers seat. I can recharge at work for free or at home for around nine quid, once every three weeks. Even when the front windscreen has been covered with ice over the last week or so, I can clear it without prior heating in around a minute using the cars own front screen heater which is like a fan heater and comes on instantly without having to wait for an IC engine to heat up.

What's not to like? There is too much negative press given to EVs most of which is in-accurate. I agree the first cost is high and problems may start to show when the car gets older. But I have no road tax, no fuel duty to pay, free parking in many places. And free charging as well at many places. Plus the greatest (to me) advantage of quiet driving with only minimum road noise. No reving petrol engine or rattly old diesel sounding like a bag of spanners. No gears or clutch to worry about and even the brake is optional most of the time. It is the easiest car to drive I have ever had.

[Pete WhiteParticipant @petewhite15172]

I can remember when overcoats were abandoned in favour of "car coats".

My landrover had a fancy purpose made variable, manually that is, radiator muff.   And you never knew when you diesel was going to wax up !

Also can't forget one of our snow clearing contrators who had a big army wagon into which he had bolted a parafin heater to the floor, not a good idea I am thinking lol.

And the only "EVs"!?  were bringing the milk, which expended on the door step and pushed the top up.!

Those were the days, it was hard when I was a lad, lol

Edited By Pete White on 25/11/2021 12:41:07

[duncan webster 1Participant @duncanwebster1]

On my commute to and from North Wales I worked out that the way to use least fuel was to not use the brakes. I once managed 90 ish miles without touching the brake, but you have to plan well ahead, and be lucky with the (very few) traffic lights. Once there are sufficient charge points I will consider an EV but they need to standardise the chargers and put them in non motorway sites. Not all of us live in metropolitan areas.

[not done it yetParticipant @notdoneityet]

Duncan,

It is much easier now. I don’t go often, but on occasions 250 miles can be achieved, without applying the brakes, on a trip to Scotland. I like to travel at night, have cruise control to play with, as necessary, so it is much easier than your commute.

There are now no roundabouts from the Dartford crossing (might be busy, but toll booth-free now) to Berwick-upon-Tweed – 6 hours would need a couple of stops…

I expect one could do possibly go from Brighton to Edinburgh (450 miles), or even further, without coming across a roundabout – but a couple of pea-breaks, or more, might be in order!

[Howard LewisParticipant @howardlewis46836]

Mentioning the Dartford Crossing, yesterday tea time (Little choice of time, unfortunately ) we had 6 miles of Stop / Start, and idle speed in first gear, with lights on, to get there..

Didn't do anything for the fuel consumption, or journey time!

Howard

[Ex contributorParticipant @mgnbuk]

Didn't do anything for the fuel consumption, or journey time!

I have been trying to reduce the depth of my ignorance about EVs over the last couple of weeks & one point that keeps coming up is that EVs seem to work in the opposite way to IC cars WRT stop-start urban operation – consumption drops rather than increases in such conditions & such conditions are where maximum range per charge is achieved.

Doesn't help with the journey time though ! Not going through the Dartford Crossing is something I do not miss – almost worth the extra cost to go North Sea Ferries to the Continent rather than use Dover crossings/Tunnel on it's own (another is not having to go through France …).

While EVs with a reasonable range at an (almost) affordable price do seem to be coming now, I'm still not convinced enough to want to take the plunge yet – still too many unknowns. One is the variability of range with changes in ambient temperature (most tests of a variety of budget EVs suggest around a 25% drop as a minimum) – my 1.6 TD Hyundai is reasonably consistent all year round (within 1-2 mpg) & I have a genuine minimum 500 mile useable range per full tank regardless of load or season at motorway speeds. My current operating mode is a 100 mile per working day commute, of which 80 miles or so are motorway – seemingly not the best mix for an EV, where range at higher speeds is reduced.

Another big question is depreciation – first generation EVs don't seem to have done too well in that regard, as buyers are wary of a vehicle with the potential for a big bill (battery issues) with only a short (or no) manufacturers warranty in place. Manufacturers appear to be cutting the miniumum capacity level that generates a battery repair or replacement – most seemed to be 75% before, but now 65/66% seems to be being mentioned. This may well work itself out with time, as more battery repair or refurbishment options become available with increasing numbers of EVs in operation, but having watched a couple of YT videos showing such repairs, they appear to entail a significant amount of work & are unlikely to ever to become "cheap".

Overall running costs (rather than just the "fuel" element) don't seem to be mentioned much, but many articles mention increased insurance premiums over IC cars (much higher groupings in many cases) & other tests mention higher tyre wear & increased service costs for items such as brakes (siezing due to infrequent use with regenerative braking) and expensive coolant changes – so how is the overall "big picture" ? From running the numbers on my IC cars I know that the biggest single cost isn't servicing, fixed costs like insurance & road tax, etc. or fuel, though, it is depreciation. A large depreciation on a higher purchase price will soon eat any fuel savings in the long run.

May be interesting to start a "General EV discussion" heading along the lines of the Motorcycle one to hear the opinions & experiences of EV owners (or would-be owners) ? Despite being a confirmed "petrol head" I am open to changes, but currently don't feel I have easily accessible answers to many questions & actual users experiences would go some way to helping with that.

NIgel B.

[VicParticipant @vic]

EV’s currently have ranges from about 90 miles up to about 400 miles. Average UK mileage is just 142 miles a Week. Battery technology is still under development and costs have come down dramatically in the past ten years. There has recently been talk of the 1000 mile battery. I do wonder though whether most drivers really want this kind of ranges or whether eventually most folks would be quite happy to change their driving habits slightly to suit the technology? New technology haters are very indignant about having to stop for 20 or 30 minutes to charge a vehicle and insist they should be able to drive 400 miles non stop. Many folks I know say they like to stop and take a break after a couple of hours anyway so that’s only 140 miles max. The answer for most reasonable folks is that we just need a lot more chargers but that won’t happen until more folks buy EV’s!

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