- Thread starter northwest
- Start date
- Status
daleyd
Member
- Messages
- 10,407
- Location
- Wrexham, North Wales
We were looking at a new car. It was a new diesel car that would cost us ~£1300 a year in fuel (plus a few hundred road tax)
OR an ev that cost ~£200 a year in “fuel” and no road tax. (Appreciate that will change in the near future)
We paid no premium for an ev, we simply spent the same money we were going to on a petrol/diesel car on an ev.
For us it was no brainer decision, based on pure maths.
If you’re buying a £1500 secondhand car then no one would argue that it’s not cheaper, or you should stump up for a new ev to save money - that’s ridiculous. But that wasn’t our situation.
OR an ev that cost ~£200 a year in “fuel” and no road tax. (Appreciate that will change in the near future)
We paid no premium for an ev, we simply spent the same money we were going to on a petrol/diesel car on an ev.
For us it was no brainer decision, based on pure maths.
If you’re buying a £1500 secondhand car then no one would argue that it’s not cheaper, or you should stump up for a new ev to save money - that’s ridiculous. But that wasn’t our situation.
Pigeon_Droppings2
Member
- Messages
- 6,402
- Location
- london
Thats basically what I did...the Tucson warranty is about to run out so wanted to replace it....so the choice is a new petrol/diesel/PHEV or EV.
If I'm honest I'd pay a bit more for an EV just to get away from the whole petrol/diesel pricing nonsense.
Something wrong with the maths, there - if you are able to get ~3.5miles/kWh, then 100 miles requires around 28.5kWh which, at £0.56/unit is £15.96, so 10,000 miles a year would cost £1596.
This assumes that the 3.5miles/kWh is the mains power input equivalent i.e. it includes the energy conversion (charge/discharge) efficiency of the battery and the 90-95% cefficiency of the charging circuit. If the 3.5miles/kWh is based on voltage and current measurements at the battery terminals during discharge only, then the true "EV fuel" costs would be higher, because of those inefficiencies.
daleyd
Member
- Messages
- 10,407
- Location
- Wrexham, North Wales
If you can charge at home you should pay ~ 9.5p per kWh on a nighttime tariff. Depends on area and supplier but that seems about average currently, we had 7.5p last year and before that it was about 2.5p!
Pigeon_Droppings2
Member
- Messages
- 6,402
- Location
- london
Cheers thats good to know...is that easy to setup with any provider?...it's a 64kwh battery so I make that £6.80 per 270 miles?
Petrol prices really annoy me because they just seem to charge what they can get away with...I can't wait to be free of that nonsense!
I thought I might mess up. I got bogged-down in the idea of comparing kwh to litres & gallons & confused myself most likely
OK... 3.5 into 10,000 is 2857 kwh required in kwh to cover 10,000 miles yes?
2857 x £0.56 is £1600 rounded up.
2857 x £0.32 is £ 914 rounded up.
If daleyd gets to do all his charging at 9.5p per kwh (my leccy is 30p per unit btw) then 10,000 miles would cost
2857 x £0.095 which is £ 271.45.
I worked out that my cheap runabout costs anywhere between 15p & 18p per mile recently, so 10,000 miles fuel cost is approx. £1650.... which is a lot, granted.
But a 40k EV will depreciate by I dunno, what, maybe 10%, maybe 15% a year? Is that a reasonable figure? That's £4k to £6k - which buys an awful lot of fuel.
Any new or pretty new car is going to lose significant money of course, not just EV's. The cost of motoring is really become expensive, and "cheap" motoring like I have always done - is being relentlessly squeezed till its eradicated.
If the situation progresses along the lines it is doing now - then by the time EV's are the only personal transport option.... then it'll be only the middle-income plus bracket that can afford to drive.
addjunkie
Member
- Messages
- 13,538
- Location
- Northumberland. Reet oot in the sticks
I cant get it, as our smart meter is dumb as it doesn't communicate, being* a very rural area. We are disadvantaged
premmington
Member
- Messages
- 6,147
- Location
- Norfolk
There are special deals for charging tariffs at home when you buy some EV cars they struggling to sell.
It is all priced into the monthly rental PHP payment. I don't know the details exactly - heard some "sales reptile" bragging about the "hard sell" the other week.
Pigeon_Droppings2
Member
- Messages
- 6,402
- Location
- london
Thats what was putting me off too...but the MG4 is £32k so quite a bit cheaper to begin with. Their warranty is 7 years so basically I'l be keeping this car quite some time. The alternative was a £34k PHEV but the mpg was terrible on the motorway unfortunately.
I looked up Octopus...they're offering 7.5p per kWh for the EV tariff...that seems pretty cheap to me.
64kwh etc.
I'm wondering if (& if yes, how they qualify & explain - which I'd be surprised if they do) the capacity of car batteries?
There's been talk of only charging to 80%, & discharging to 20% to look after batteries (sounds about right). So, if they just give the full-to-flat value (which is how batt mfrs have always used as the power rating historically) - then your 64kw USABLE is more like 38.5kw.
(64kw at e.5 miles per kw is 224 miles. So if your new car is capable if 270 miles, then it must do more like 4.21 miles per kwh if you have 64kw you can actually use. If your usable was closer to 40kw, then to hit 270 miles range, your car would need to do 6.75 miles per kwh).
Then.... do they qualify the built-in Safety's & settings of the charging system & software?
"Not done it yet" was rattling on about the driver limiting his charge to 80% & not discharging below 20% ...... the thing is - I'd expect the Mfr to have preprogrammed this into the system to protect the car from its owner - meaning the display visual of battery percentage - might well disregard the "hidden" top & bottom 20%.... so your displayed 100%, might only be a REAL state-of-charge - of 80%?
Perhaps because I've not owned or had chance to have any data from an EV - these answers are provided and are backed up by owner figures of Kwh put into the car, and the actual mileage extracted from those kwh.
I for one would be very interested to hear from you just what you find out, & just what you actually get from your kilowatt-hours IN, and resultant mileage OUT.
Ubique
Member
- Messages
- 2,284
- Location
- East Midlands
I'd imagine that's it's very dependent upon driving style and time of day - the same with ICE powered vehicles. On a run I get ~36mpg (4.4SDV8) weekday commuting is 27mpg, that said, the heating/cooling overhead is negligible. Regen isn't going to do a whole lot in <15-20 mph traffic either.
Pigeon_Droppings2
Member
- Messages
- 6,402
- Location
- london
addjunkie
Member
- Messages
- 13,538
- Location
- Northumberland. Reet oot in the sticks
Youll need your connection checked by your dno too, when you install a charge point at home
Just to add to the questions - it'd be good to know what criteria & test system the mfrs are using when arriving at their battery AH or kwh rating.
There's ways to get a more impressive rating, and another to get a more "real" rating with Lead-acid cells, so it's a fair guess the same applies to L-ion (but I don't know).
With Lead-Acid cells, there's 2 common Test paths to get a Rating. The first (& most common, used for starter batteries & leisure batteries (even pretty big ones) is to discharge a cell with a load that fully discharges the battery in 20hrs (the small print on a datasheet will have this buried somewhere).
The 2nd path us the one we'd see for Deep-Cycle Traction cells (fork lift & similar industrial stuff).
These cells apply a load that fully discharges a cell in 5-hours (25% of the time of the other batteries).
So, you can have 2 cells, both with the same AH rating - but tested very differently! And.... because the 5-hour discharge is deleting the cell faster, using a much bigger load, in reality the Traction cell is far stronger & superior to the Leisure cell, despite the rating looking the same.
If I were ever to want/need/have to buy an EV.... then the questions in my previous post, AND the method of rating the pack, and the true usable AH/Kwh - are things I'd want to know (& you can guarantee any bull$h1ttjng "Sales Reptile" wouldn't have a clue about).
Otherwise you cannot have a hope of knowing whether you're comparing apples with apples, or apples with foot powder (model to model) .... or just how real your storage KW are.... till you get it home & do the maths in use (& not rely on what the Dash tells you..... & I suspect 99% of customers don't do their own checks/calcs)
There's ways to get a more impressive rating, and another to get a more "real" rating with Lead-acid cells, so it's a fair guess the same applies to L-ion (but I don't know).
With Lead-Acid cells, there's 2 common Test paths to get a Rating. The first (& most common, used for starter batteries & leisure batteries (even pretty big ones) is to discharge a cell with a load that fully discharges the battery in 20hrs (the small print on a datasheet will have this buried somewhere).
The 2nd path us the one we'd see for Deep-Cycle Traction cells (fork lift & similar industrial stuff).
These cells apply a load that fully discharges a cell in 5-hours (25% of the time of the other batteries).
So, you can have 2 cells, both with the same AH rating - but tested very differently! And.... because the 5-hour discharge is deleting the cell faster, using a much bigger load, in reality the Traction cell is far stronger & superior to the Leisure cell, despite the rating looking the same.
If I were ever to want/need/have to buy an EV.... then the questions in my previous post, AND the method of rating the pack, and the true usable AH/Kwh - are things I'd want to know (& you can guarantee any bull$h1ttjng "Sales Reptile" wouldn't have a clue about).
Otherwise you cannot have a hope of knowing whether you're comparing apples with apples, or apples with foot powder (model to model) .... or just how real your storage KW are.... till you get it home & do the maths in use (& not rely on what the Dash tells you..... & I suspect 99% of customers don't do their own checks/calcs)
It was on an EV thread fella, & at the time (SURPRISE!) EV Vans was being discussed.
I really do wonder how you've lived so long, I truly do. With your appetite for aggravation (if you're as combative in real life), either you were the Rambo as a younger man, or you regularly woke up with a crowd around you after someone administered some "attitude adjustment therapy" (that you weren't smart enough to learn from).
I have two words for you:
SEEK HELP!
willie.macleod
Member
- Messages
- 895
- Location
- Western Isles, Scotland
I think you'll find quite a few EV owners do their own calcs - they have accurate records of power supplied by their chargers, a large number of them are logging the data and every public chargepoint that they use is as well. EVs can not only record the miles but the power breakdown of the usage per trip which can be quite interesting.
If you go to https://ev-database.org you will the nominal capacity and the usable capacity of each EV, there isn't a massive difference between the two for most manufacturers, not sure who is the worst culprit. Modern EV batteries behave very differently from lead acid and manufacturers are backing their batteries with decent warranties thanks to their massive data sets collated over many years which give them the confidence to do so. C rates charging are more of a problem than C rates discharging on road cars thanks to the general publics desire to try and get energy into the cars in a similar timescale to refilling an ICE!
premmington
Member
- Messages
- 6,147
- Location
- Norfolk
Your quote "I am holding off making my decision re supplier and tariff, at the present time, because my wife has not long to live, so my personal circumstances are bound to change in the very foreseeable future."
I am really sorry to read this mate. I trully really am....
I'm aware that the L-ion batteries behave differently - but it's hard to tell by just how much.
It seems that there are still many similarities in behaviour (as you might expect), and the general rules for charging & discharging (in general pattern if not in specific numbers) also seem to apply (I.e. don't force-charge & don't hammer the performance if you want to get anything near the estimated range & lifespan).
With a liquid fuel, the octane rating, & the strict standards regarding fuel consistency, plus the accurate dispensing measurement into a fuel tank of fixed volume - make it pretty easy for anyone to work out what they are getting for their money - as everything is pretty much a consistent constant (except the price!).
IMO it seems not so easy (yet) in the EV world, and not as clearly defined (& we all know that the sellers will exaggerate & inflate (but yes, some more than others) to get the sale unless strictly regulated.
The consumer needs to have a system where the comparison & data between vehicles is all measured & presented in exactly the same way.
- Status
