My Skoda Superb 4wd was predominately biased to the front with about 10% going to the rear drive. However it wasn't until I had service that the diagnostics picked up a problem with the rear drive, subsequently found to be a failed Haldex pump. Did not notice any difference during normal driving and no idea how long it had been failed. However, the Subaru Forester is 4wd all of the time with a normal balance of neigh on 50/50.
Do you mean your Touareg? 4Motion is just VW's generic term for 4wd, covering the Haldex system on transverse-engined cars as well as the full-time 4wd used on Touareg and uses a Torsen centre diff to vary the front-rear split from it's nominal 40:60
Just a general point to explain the variations. The Fiat Panda 4x4 was something els3 😉
We had the Countryman PHEV in the winter; it had no petrol in it (our SE had a recall for a software update) so it had to run purely on electric=30miles or so range. I enjoyed it but it wasn't -10 . There is some internet chatter about the Countryman starting on petrol even if fully charged, then when the batteries warm, it switches to full electric if demanded, reason being to protect the cold batteries. Some SE owners report reduced power in really severe conditions and if you haven't preconditioned the batteries; bit like warming up an ice!
The variations of 4wd/AWD are very wide - and many models have had major changes over their production run.
The generation 5 haldex system is never 2 wheel drive.
VW did have all the technical facts on their website.
Whilst PHEV's do indeed have both ICE and Electric power, the way the power/torque can be delivered they're often less powerful than many pure EV's and some pure ICE versions.
As an aside I see Parker’s, the car guide people , now quote MPP. A very useful and meaningful tool imo.
Used as a yardstick for comparing how much fuel or energy all types of cars use, the miles per pound (mpp) figure helps people decide between different options by showing in simple terms how far you can go for your money.
Why miles per pound?
Used as a yardstick for comparing how much fuel or energy all types of cars use, the miles per pound (mpp) figure helps people decide between different options by showing in simple terms how far you can go for your money.
Why miles per pound?
It's increasingly difficult to use a system like "mile's per £" as one of the major components is the cost of fuel, or energy, so any such calculation is only accurate on the day the data was collected.
In fact all the common methods used to assess the fuel efficiency of any car are so affected by variables non of them will be accurate, and as we have seen with some of the figures from manufacturer's many are almost cloud cookooland optimistic, especially for hybrids. Look at how they often quote the fuel efficiency of PHEV often over 100 miles per gallon, but it's only achieved by using mains power to charge the battery, and the effect of that interms of energy used and it's cost is not included !
The best we can hope for is to use economy figures as a basis for comparison, assuming the methodology used is consistent.
I would much prefer to see a calculation which is based on a common set of factors such as energy used per unit distance or distance per unit of energy. I get the impression that the public are getting the hang of kWh, and it is fairly easy to convert a measure of petrol diesel or any fuel and to express it's energy content in the same way, so it should be possible to know how much energy has been put into a vehicle, and therefore what it's energy economy is even for multi-fuel vehicles such as hybrids, and express it. These figures won't change with prices. It would be up to the owner to work out the cost of the energy they use.
However this would still require the consumer to understand they are still only any value as a means of comparing vehicle efficiencies, and it's highly unlikely an average driver could match them in real driving conditions.
Similar issues surround the other running costs, Insurance and VED, these are all variables, and as a result the magazine's published figures will rarely match your personal experience.
I like the idea of normalising the energy used to kWh. It would allow a real comparison of ICE and EV, as well as petrol and diesel.
If a litre of petrol is 9.7kWh of energy, and an imperial gallon of petrol is 4.54 litres, one gallon holds 44.038kWh of energy. Diesel is a little more energy dense at around 10.7kWh/L, so 48.58kWh per gallon.
So to get mpkWh, just divide the mpg figure by 44 for petrol and 48.6 for diesel.
Using these numbers, you can quickly compare the energy efficiency of any pure ICE cars, and indeed any pure electric cars over whatever is the standard measure.
So, a petrol car achieving 44mpg (our Kia Picanto 1l on a run) is 44 miles per (4.54*9.7) kWh or 44.039kWh or 1 mile per kWh (mpkWh)(near enough). Normally its more like 40mpg or 0.91mpkWh.
Our old XC90D5 diesel used to get about 32mpg on a good run (22mpg round town) or 0.66mpkWh (0.45mpkWh in town).
The Polestar 2 EV on the same run, round 32kWh/100miles or 3.12mpkWh. I.e. nearly 3.5 times as efficient as the Picanto, and over 4.5 times as efficient as the XC90.
However, today it falls down for PHEVs quoted efficiency figures because (as @ProfJohnL points put) the electrical input associated with the MPG figure for a PHEV is ignored in the NEDS or WLTP figures. But for PHEV, it's a little moot as the retuned efficiency is HUGELY dependant on the journey involved.
For example, my PHEV (Volvo V60 D6) will do around 25 miles on electric only. That will require about 10kWh of electricity. i.e. 2.5mpkWh.
In diesel only mode, it does about 42mpg on a run, or (42/48.6) 0.86mpkWh.
I.e. when running from electricity added from the grid it is close to three times as efficient as when running on diesel from the pump, (same as the Polestar vs the Picanto).
This is why it is SOOOO important to always charge a PHEV, and just as important to have the right use case for it.
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Cost per mile has been around for a long time, but it covers things such as depreciation, along with fuel costs for a fixed mileage.
Still the miles per pound is another useful tool.
Still the miles per pound is another useful tool.
It is useful, but SOOO dependant on prices. I looked at my Polestar. They quote 6 to 13.2 miles per pound, based on (I believe) WLTP figures and household vs public charging. That makes some sense. 6mp£ is about right for my 3.1 mpkWh charged at 49p per kWh in public. Public rapid chargers are indeed around that price. But last week, I was public charging at 30ppkWh or arround 10ppm or 10mp£. At home, I pay 7.5ppkWh overnight, or 2.5ppm or 40mp£. for 13.2mp£ you would need to pay 24ppkWh. Still possible.
How about he picanto? Well at 170 per litre, 1 mile per 1 kWh, 170/9.7 = 17.5ppm or 5.7mp£. Parkers say 5.6 to 8.0 mp£. Seems about right for todays prices, when driven as efficiently as you can.
I don't blame you Dusty, all the conversions are a nightmare. Quoting an EV in MPG equivalent in another way of doing it. For mine it is 318mpg when charged at home, 47mpg when charged on a public rapid, based on £1.70 a litre for petrol.Good scripts chaps but sadly lost on me. I’ll stick to MPG and Ilbs and ozs
I don't see the value in MPG equivalent for an EV - if I ever get an EV, I'd work in Miles per Kwh - but then I disregard NEDC and WLTP MPG figures as useless for IC cars anyway.
The American EPA City and Highway figures are much more useful - no point changing now for IC cars but they're useful for EVs, at least useful where the same model is sold in the UK.
Yep - comparing EVs via MPG is pointless (as it relies on cost of petrol or diesel to be useful). But if you want to figure out how an EV will (or wont) fit your use case, knowing how much it might cost you (or save you) in todays prices can be useful. Thats what Parkers miles per pound is attempting.
Tobes, Thank you . The ordinary man in the street can relate to that even with the 0.001 variations 😜
I always convert our Mini to MPG equivalent based on the current cheapest petrol in our area and our pretty awful unit cost for electricity which has now rocketed. Makes me know I'm saving and it has always been ingrained in me by my dad from birth! At Current prices for both electricity and petrol are giving us 140mpg ; we rarely charge away from home. We've only just got a smart meter so couldn't have any ev specific tariffs and of course, now they won't even quote you to change so we'll have to wait till hopefully things settle down a bit!
I believe if you call or message Octopus (rather than look at the web page) they will offer you a go! Tariff. If you are not already with them, I have a referral you can use.
Brilliant; we're sticking with BG till June then will do some maths-last reckoning we didn't do enough EV charging to make the extra expense of day units on og pay, but it may well be v different now and we can maybe add timers to the spa to help! Emersion timers are for higher current draw!
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