Is Ideal Range obtainable?

[CarbonOne]

I herd somewhere that the battery needs a little wear and tear in order to be able to retain the maximum amount of power?

Also, I'd think that stop and go traffic is good because of the brake regen?

Also, I think a good reason most people do not reach the potential I because of the soft top. No top is worse, but hard top is the best.

 

[strider]

I have a story about the Prius. I rented one in Los Angeles. I wanted to see how bad I could make the gas mileage. I drove about 250 miles with this car, Jackrabbit starts, floored it wherever I could 80 mph on the highway, used the brakes hard, etc. I still got 41 mpg! I was shocked and impressed.

Prius's (Priuii?) are kind of common to be used as taxis around here - I've been in several and have never seen one showing over 31mpg average. Also, see the Top Gear test where an M3 got better mileage than a Prius - doing laps at a racetrack

 

[dpeilow]

I agree with Lloyd, I rented one for five days when in CA, did all the same things and got 44 mpg average.

 

[Alan]

He says that he hits about 325 kw/mi when he drives aggresively.

Your dealer needs to try harder. Expect to see >500 kw / mile when you are having lots of fun!

 

[Nik]

Also, I'd think that stop and go traffic is good because of the brake regen?

Stop and go is where the EV had the maximum advantage over an ICE, but overall the constant speed is best. There are always losses when braking and accelerating.

 

[tennis_trs]

...Also, I think a good reason most people do not reach the potential I because of the soft top. No top is worse, but hard top is the best.

I haven't seen a noticeable difference in range between soft top and hard top over many iterations of the same relatively high speed 100 mile trip. But I've only checked based on range left at the end. I'll try paying attention to the updating kWh/m for constant speed to see if I notice a difference.

Has anyone noticed a difference?

 

[dsm363]

tennis_trs: Is the wind noise better with the hard top? It sounds like I'm driving with my window down when I have the soft top on (with both windows up). Thanks.

 

[mpt]

I don't think the reduction in cold weather range is due to battery heating; I don't think that it heats the battery during driving, only during charging.

I assume that the reduction is due to the cold battery - it's just not as good at storing and releasing the power at lower temperatures.

The MINI E displays this big time as it has no thermal management. In nice weather the range is 128 Miles and it pans out, in the cold, 90ish regardless of how we drove yesterday yet it often struggles to cover 70.

 

[tennis_trs]

tennis_trs: Is the wind noise better with the hard top? It sounds like I'm driving with my window down when I have the soft top on (with both windows up). Thanks.

Wind noise, to me, seems moderately reduced with the hard top compared to with the soft top. But, based on other threads, it seems like wind noise seems to vary a good bit car to car (I assume due to variability in the weather stripping, including whether the car has the stripping that Tesla added later and also window to top fit).

Next time I switch I need to get in some highway driving the day before and the day of the switch and pay more attention, so I can better answer this question in the future.

 

[dpeilow]

MPT - I saw what looked like heating on my Scotland trip. When we left London I couldn't work out why the consumption was up in the high 300s even in a 50 mph stretch. Then further up the road is suddenly fell back to 290 when at 70 mph. Later we saw the high 300s kicked in again. We saw this several times on the trip. I can only guess at heating causing that sort of behaviour.

 

[Doug_G]

We saw this several times on the trip. I can only guess at heating causing that sort of behaviour.

Interesting. When I had my car out at -26C, I was seeing significantly higher than normal power consumption at first. It appeared to return to normal around the time the regen enabled. I didn't drive far enough to see if it increased again.

I would have thought that simply using the battery would produce enough heat to keep it warm.

 

[WarpedOne]

Also, I'd think that stop and go traffic is good because of the brake regen?

No, regen recuperates only about 50% of kinetic energy, other half goes into heat. Going at constant speed is most efficient way to travel from A to B in time T.

 

[benji4]

Today I did better than on my first few days --- first of all I switched units to mi instead of km because the 2km decrements in range are just annoying really. Anyway, temperature outside was about 2C again, lots of stop go, waiting at lights, etc. I didn't go faster than 40mph as again it was all city driving... Total of 20 mi driven, ideal ranged decreased by 23 mi, so only missed by 15% this time. Wh/mi came in at 265 for the trip... looks like I'll need to keep it under 250 to hit ideal range which I'll aim for tomorrow on a 150 mile drive on the expressway. This will be my first test out of traffic and out of the city.

 

[dsm363]

I believe you will actually get farther from ideal range (lower number) at non-stop highway speeds since that uses more energy.

 

[Nik]

MPT - I saw what looked like heating on my Scotland trip. When we left London I couldn't work out why the consumption was up in the high 300s even in a 50 mph stretch. Then further up the road is suddenly fell back to 290 when at 70 mph. Later we saw the high 300s kicked in again. We saw this several times on the trip. I can only guess at heating causing that sort of behaviour.

Could road surface be a cause? Some of the high-drainage tarmacs have a much higher rolling resistance than the smoother ones.

 

[mpt]

MPT - I saw what looked like heating on my Scotland trip. When we left London I couldn't work out why the consumption was up in the high 300s even in a 50 mph stretch. Then further up the road is suddenly fell back to 290 when at 70 mph. Later we saw the high 300s kicked in again. We saw this several times on the trip. I can only guess at heating causing that sort of behaviour.

Hmm, it does seem feasible; 300 is firm driving which I'm sure you weren't doing on a distance run, you should have been in the 220-250 range. Did you have any heat on? I've see 300+ first thing with heat on as it's 4kW thermostatic so it's on full blast for a short initial period. But, I thought the car had just come off charge so it should have been toasty.

Interesting. When I had my car out at -26C, I was seeing significantly higher than normal power consumption at first. It appeared to return to normal around the time the regen enabled. I didn't drive far enough to see if it increased again.

If you charge to full on range mode, the first few miles before regen do register in the 300's. I feel (hunch here) that the regen might accounts for 50kW/hr in stop/start. Ah Ha! this also explains what David saw; if he was on a full charge (DP please confirm); no regen hence in stop/start traffic seeing 300's. What about the later 300s though.

I would have thought that simply using the battery would produce enough heat to keep it warm.

That is my understanding; that usage creates more than enough heat.

Could road surface be a cause? Some of the high-drainage tarmacs have a much higher rolling resistance than the smoother ones.

Could be but inner city London where DP started is nice.

 

[Doug_G]

If you charge to full on range mode, the first few miles before regen do register in the 300's. I feel (hunch here) that the regen might accounts for 50kW/hr in stop/start. Ah Ha! this also explains what David saw; if he was on a full charge (DP please confirm); no regen hence in stop/start traffic seeing 300's. What about the later 300s though.

My situation was different - regen was disabled because the battery pack was cold.

 

[WarpedOne]

Could road surface be a cause? Some of the high-drainage tarmacs have a much higher rolling resistance than the smoother ones.

Cause no, a factor yes.
Road surface friction could vary about 5% and cause up to 3% change in energy consumption. Of course, a lot of water or snow on the road raises this number much higher.

Take a look at the charts at Tesla Motors Blog. Most efficient driving is constant speed between 30 and 50 mph. Stop'n'go and > 60 mph waste energy.

 

[mpt]

My situation was different - regen was disabled because the battery pack was cold.

Same result though, you were at 100% consumption.

It's at times like this that a Tesla Tech would be a great help but, I expect that this stuff really is the secret sauce.

 

[dpeilow]

We didn't have heat on at that point. It was on the first part of the M1.

I normally see 280-300 Wh/mile on the motorway with the cruise control on.