Hi

Mine also gives me around 218 on a full charge. Especially in colder temperatures. You may find small variations in your actual range depending on driving style. But i've never got more than 250 miles from a 'full tank'!

 

Morning it’s correct, just charged mine and I am showing 212, recent cold weather has reduce mine from 240 a week ago. Most I have ever had is 260 in the past 2 years taking it easy in summer.
Remember heated seats steering wheel demisters AC all reduce your range.
i use them all, rather stop 30 miles earlier and be comfortabl.

 

It's getting cold. Range drops by around 15% to 20% in winter, compared to summer. Same is true of ICE cars, but with them it's far less apparent as the range on a full tank is usually a lot higher.

 

ICE cars also have huge amounts of waste heat that they throw away in the summer but can use in the winter. We, on the other hand, have to use the on board fuel to provide the necessary heat in winter.

 

Thank you for the responses.

 

I have just come on to ask the very same question - if the estimated range does reflect the weather conditions (and so it does!). I have also just purchased an i-pace on Tuesday and it is showing 220 miles fully charged. It was a 258 mile journey home and it took 110kw to make it with 17 miles remaining on the clock (on the basis there was 80kw available when fully charged on pick up). The weather was dry but cold (1-3 degrees so heater on!) and 230 miles were on the motorway cruising at an average of 70mph (60% of the journey was also with headlights). I didn't think that was too bad?

 

I am looking forward to summer to see what full charge is.

 

Make sure you charge enroute before it gets to 20%, it will charge quickly when the battery is warm up to 80% when it slows down, whatever the charger rating the car regulates the charge and 80KW is usually the best you will get.

Lights, heater, wipers all use power and wet roads Increase rolling resistance, rain means poorer aerodynamics too, so don’t get caught out with high consumption in bad weather

 

Good advice Delta, thank you! I had not intended to cut it so fine but once you leave the M5 and get over Exmoor into North Devon there are very limited options. The nearest charge point to me is an hours drive (there and back). I was somewhat concerned as the mileage also seemed to rapidly diminish at the end!

 

Hi Ib, my 22/23 behaves differently to my 18 and I have 218 now the weather has turned cold. But, when driving off, after a couple of miles it shows up to ten miles more. I think that this is the weirdness of PiviPro over the original system and you can’t reset GOM on PiviPro Like the original model. Generally in the summer I was getting 240 but my son, who has my 18 car, regularly got 270. I also use a granny being on solar PV and a battery with IO. Clive.

 

Charged the i-pace to 80% overnight from 50%, GOM showing 207 miles -1 C. MY22. I always switch the ECO mode on ( irritating you can’t set this as default). On motorways I set the max speed at 66 mph. Checking the mileage against the initial GOM reading I find it is fairly accurate.

 

Hi rjevansuk, at 100% charge that would be a GOM of 250 at -1, that is impressive! Can I ask why 66mph, is that a speed you have found to be the most economical?

 

I saw it in a youtube video about EVs, can't remeber which channel.

 

Indeed speed has a direct correlation to consumption as in an ICE vehicle. Travelling to Scotland in my latest 22/23 at around 80mph, the consumption was 58kWh per 100 miles! Sticking to just below 70, I seem to be able to achieve 38kWh per 100 miles. Clive.

 

That is considerable, so much so it is almost unrealistic to travel at the higher speed (unless it is a short journey). Can you get real time kw/hr usage (consumption) or just an average for the journey? Sorry I am being lazy - only just bought the car!

 

Worth remembering that the dominant force that a car drive system has to overcome is aerodynamic drag. Tyre rolling resistance is both small and doesn't vary a massive amount with speed. Aerodynamic drag rises in proportion to the square of speed, but the power needed to overcome aerodynamic drag rises in proportion to the cube of speed.

As it's power taken from the battery that directly impacts range, even allowing for the shorter journey time at higher speeds it's clear that a small increase in speed can result in a very much larger amount of power being needed, which in turn leads to a net increase in the amount of energy used per mile.

To add to this, there are losses in the power delivery system that also increase as power increases, for example the resistive (I²R) losses in the battery, wiring, motor controller and motor windings will increase in proportion to the square of the current flowing through them, so adding another non-linear source of overall energy loss per mile.

 

Thank you slartibartfast, much appreciated - I think they call that a double whammy (the cube and the square)! Does that imply the greatest range would indeed by garnered by advancing at 1mph (notwithstanding a constant drain regardless of speed for instruments etc).

 

Unfortunately it's not that simple, as there is always power being drawn from the battery when the car is turned on (running the heating, aircon, lights etc). This power depends on temperature as well, so will be higher in cold weather and hot weather. At one mph this power draw will probably exceed the power needed to move the car.

There will be an optimum speed for range that's somewhere where the power per unit time drawn by the car's systems and the power used per unit time to overcome aerodynamic drag, rolling resistance and I²R losses, together with the length of time the car is in motion, are at a sweet spot. Not sure where this is, but if I had to take a rough guess I'd say it's probably somewhere around 50mph.

Higher speed has a markedly more detrimental impact than lower speed, so even a 5 mph increase in speed may have a marked impact in terms of reducing range per charge. I'll chuck in that cold air has a higher density than warm air, so aerodynamic drag (which is linearly proportional to air density) also increases as the temperature drops.

 

I am surprised someone hasn't looked into this on some level or other although I suppose it depends on so many other factors (weather, temperature etc). Nonetheless on a reasonably calm day I do wonder what the ultimate speed for range would be. If it is 50mph, ironically that is pretty similar to what has been quoted over the ages of IC engines (55mph). Again this might reflect that it is indeed resistance that is the greater factor.

 

Drag from air resistance is indeed the predominate absorber of power, and isn't affected by the motive power source, so EVs are no different to ICE vehicles where that's concerned. Where there is a difference is with power needed for heating the cabin, which with an ICE vehicle comes partly, but not wholly, from waste heat from the engine.

This is the reason that car manufacturers have focussed so much on reducing the aerodynamic drag coefficient, Cd. The IPace isn't great in terms of aerodynamic drag, due to its relatively poor Cd of 0.29 versus, say, 0.23 for the Tesla Model 3 (the IPace is roughly 20% worse).

Also worth noting that the IPace doesn't have such an efficient drive train as that used in Teslas, for example, and this adds to the losses.

 

The principle reason for the higher CD is frontal area, because the IPace is an SUV frontal area is much larger, than a Model 3. Compared with other SUV body styles they are similar.

 

No it's not, Cd is a non-dimensional coefficient, so it has no connection to projected frontal area. The aerodynamic drag equation is D = 0.5 * ρ * Cd * A *V², where ρ is the air density, A is the projected frontal area and V is the velocity through the surrounding air (so is impacted by wind speed and direction as well as vehicle ground speed).

There is a commonly used aggregation of Cd and projected frontal area used in the automotive world as a way of comparing one vehicle with another and that is CdA, which is just a part of the drag equation, Cd * A. It's useful, as it allows a fair comparison between different size and shape vehicles.

For example, the IPace has a CdA of about 0.29 * 2.4m² = 0.696, whilst the Tesla Model 3 has a CdA of about 0.23 * 2.18m³ = 0.5014.

 

And remember that heating also uses heat from the traction battery which heats up during discharging. Clive.

 

Interesting one that, as in reality the heat generated during discharge is very tiny, just a couple of hundred of watts or so, less at low speeds. I can't see the battery contributing to the car heating, it most probably has to be heated in cold weather from the waste heat from the motors, I think.

With the car the average discharge rate from the battery pack is pretty low. If we use the figure in the title of this thread as the winter range, 218 miles, and take a high average speed of 50mph for the whole of a 218 mile trip (so the trip takes 4.36 hours), then the average power (using the battery usable capacity) drawn from the battery will be about 19kW. The battery internal resistance is about 70mΩ and the battery voltage is about 400VDC, which makes the current at 19kW about 47.5A. From P = I² * R the heat generated within the battery will be about 158W. That's not going to raise the battery internal temperature by any noticeable amount, it will just be lost through the battery case I suspect.

 

The aerodynamic drag equation is D = 0.5 * ρ * Cd * A *V², where ρ is the air density,

If CD is non dimensional how is it measured

 

The aerodynamic drag equation is D = 0.5 * ρ * Cd * A *V², where ρ is the air density,

If CD is non dimensional how is it measured

By deduction and the measurement of all other variables in the equation. Back in my day this was done practically, we'd put a model in a wind tunnel, with a load balance that measured the force vectors acting on it so the net force acting on the model could be determined, then move air over the model at a known velocity. Because the air density was known, the projected frontal area was known and the air velocity and forces were measured, Cd could be derived by just rearranging the drag equation. Nowadays I suspect it's mostly done using mathematical modelling, but the principle will be exactly the same.

There are lots of other dimensionless coefficients around, perhaps one we all feel the effect of every day (and especially now with ice around) is the coefficient of friction, µ. This is another empirically derived dimensionless coefficient that describes the ease with which two materials will slide across each other.

 

Good stuff @Slartibartfast. A lot of people forget the the Cd alone means nothing. So comparing the Cd does not give you a clear indication of efficiency. If we compare the Model Y to a Model 3 with identical Cd, we can see the Model Y is about 15% less efficient as it is bigger (more frontal area). Though it is also heavier as well.

 

The I-Pace would rather scavenge heat from the atmosphere, and then from the motors, before using the HV heater. Once the motors, and controlling modules cooled by the coolant, get warm the HV heater is used less. However, the traction battery uses its bottom plate as a heat sink for the cell modules. In winter, it provides a lot of cooling when the battery really needs heating. It often prevents the battery from getting up to optimum temperature even on non-stop long-distance drives. This will cause the HV heater to be used to heat the HVAC/motor coolant that will flow through the heat exchanger to transfer heat to the traction battery coolant. Thus, the potential distance to travel on a charge gets reduced due to the cooling of the modules and the need to heat them with the HV heater.

I suspect that the impact of this on range is likely to be lower than the impact of the increased air density in cold weather. Cold, dry air is denser that warm, moist air by a noticeable amount. This alone means that aerodynamic drag will increase by about 8% between driving in air at 20°C and driving in air at 0°C. If the warm weather range is, say, 250 miles, then just the effect of increased air density at 0°C will reduce range by about 20 miles. I'm sure the effect of heating the cabin, defrosting/demisting the screens and mirrors adds to this, no idea how to estimate how much, but my gut feeling is that it might knock another 10 miles or so off the range.

I have traveled long distances of over 150 miles at motorway speeds (55-70 mph) without stopping in past winters. The battery is cold enough when I arrived at a DCFC that it engaged heating of the battery. Sometimes it wouldn't charge above 30 kW rate even when starting at about 10% SOC.

I agree, I've seen the same with our house battery. It has an internal temperature sensor and the temperature just doesn't change when charging or discharging, even at the max charge/discharge rate of the system of about 0.14C. The Ipace typical cruise discharge rate is broadly similar, around 0.2C, so not very high and not high enough to raise the battery temperature by much, if anything.

 

This is just the GOM -just zero it it takes two minutes!!!