Energy Consumption

It is probably from the car. There is no way for OnStar to get kWh from every wall socket / charger that you came across.

If I am right, the charger losses are not included.

 

Again, I personally have no idea, but couldn't they measure the current into the charger just as easily as the current out of the battery (keeping in mind the charger is internal to the car, the stuff outside is just cordage)?

 

I thought Volt stores 10.6 kWh but uses 12.9 kWh from the wall using the fast charger. That's 22% loss.

If you use the slow charger, it may explain the 15% loss.

 

I got my gasoline consumption number. Its 62.2 gallons to date. Assuming it was all used for propulsion (as opposed to engine maintenance or thermal management) over those non-EV miles (2232) that puts my lifetime gasoline consumption in CS mode at a rate of 35.9 mpg.

mpge:

I am not certain I have the proper conversion values. But it looks like over the 4,889 EV miles I consumed 1.66 Mwh or 5.67 million btu's. I get that the 62.2 gallons consumed 7.18 million btu's. Collectively then I consumed 12.85 million btu's, which I get would be the energy equivalent of 111.35 gallons of gas which spread over the full 7121 miles should give me 63.95 mpge.

For comparison I get that a 50mpg car would have consumed 16.43 million btu's, or 142.4 gallons.

 

The PHV prototype requires 3.56 kWh to charge according to Toyota and verified by various testers.

 

The math seems right. You beat EPA combined estimate of 60 MPGe for the Volt. Isn't it a bitch to figure out your MPGe? I hope Prius PHV shows the combined MPGe on the dash.

MPGe assumes the energy it takes to create electricity is the same as refining gasoline. In Delaware, 42.2% of the electricity is generated from Coal so you'll have to consider mining, transporting and converting it to electricity. 13.1% is from natural gas. 1.1% is from oil. 40.3% is from nuclear. The remaining ~2.2% is from hydro and other renewable power sources.

In your case, I don't believe the MPGe is accurate since majority of your electricity came from fossil fuel with conversion loss of about 50%.

 

What's your source for it? The prototype's pack has 5.2 kWh. If it is using only 2.8 kWh, that's only 54% SOC swing.

 

I am trying to keep the mpge calculation (in my own figuring) to the energy used by the car regardless of the upstream consumption. For example I used the btu's in a gallon of refined gasoline, not the barrel equivalent figure for unrefined crude oil. Given that everyone's upstream energy use will vary drastically, I think looking only at the car (pump to wheel or wall to wheel as opposed to well to wheel) will be the best tool for comparisons.

Where I think my calculation is most inaccurate is in not accounting for the charging losses, I'll recalculate later assuming 15% more electricity consumption.

on the 54% PHV pack usage that would not surprise me. I believe the best possible scenario for conservative long use of life would be 50% usage from about 80% down to 30% SOC.

 

Thanks, I see how you derived it. The charger loss seems very high but then it is a prototype. On the plus side, 14 miles out of 2.8 kWh is very efficient. Can't wait to find out the production spec.

 

New personal record for efficiency for my Volt this weekend.

Saturday I drove 83 miles round trip. I got 47 miles of all electric range (with no mountain mode shenanigans or additional charging). Then on the way back I used 0.76 gallons on the last 36 miles, for a CS mode fuel efficiency of more than 47 mpg.

Now it was all smaller country roads, mostly around 45 mph, so its pretty close to best case scenario (might have hit 60 for a very short period). Also there was little to no other traffic so I was able to coast down to stop signs using the "L" gear selection (heavy regen), so I was pretty much hyper-miling but I don't claim much skill at it.

Other than not being in much of a hurry and slowing down with regen instead of the hydraulic brakes I wasn't doing anything special. I'm fairly certain now if I work at it I'll be able to personally break the 50 mile electric range mark.

 

It turns out it is not that simple. Remember the prototype has 3 sub-packs, 2 PHV and 1 HV. Only the two PHV sub-packs gets charged from the plug. The HV pack is left alone. Those SOC reported from SGII must be from different sub-packs.

 

August efficiency report:

Fuel Economy: 134 mpg

Electric Consumption: 34 kW-hr/100 miles

Electric Miles: 1,153

Gas Miles: 461

Total Miles: 1,614

Percentage on Electric: 71 %

Estimated Gallons of Fuel Saved:
Click here for important calculation details. 50 gal

Estimated CO2 Avoided:
Click here for important calculation details. 985 lbs

 

The Chevy dealers aren't promoting the Volt at all. The Sunday papers were loaded with car advertising--no mention of Volt in the Chevy ads.
They are pushing their trucks, SUVs, ICE cars. No changes there.

I did notice used Priuses are commanding a premium. '10s are going for $22K, '09s $20K, '08s $18K, '07s $16K. Toyota dealer prices.

 

I'd like to see more of a marketing campaign to help educate the public, but I also understand not spending a lot on advertising while the production numbers were down (wouldn't do anyone good to have people show up at dealerships excited about the car and finding out they have to wait a few months).

The other day my paralegal's son came into the office and asked her why my car was plugged in. She explained its because it can run on electricity, and he responded "oh it must be one of those hybrids".

It irked me not because I don't realize it is a hybrid, but because there are still a huge number of Americans who think Prii have been plugging in all along and just don't get it.

 

The 2012 Volts are showing up at the dealers now.

 

Toyota spent a lot of money telling people a decade ago that the Prius cannot be plugged in, because plugging in was viewed as a negative attribute. It still is for many.

 

Interesting new development this morning, I got the "Engine Running Due to Temperature" message for the first time.

Temps were in the upper teens and I did not properly preheat the car (started it only a minute or two before going out when I picked up my keys). Climate usage was high as on school mornings passenger comfort for the kids in the back trumps efficiency.

The initial range estimates showed 24 miles EV and 47 gas (close to needing to fill up). When I started the car the ICE was running immediately and the message was displayed on the screen in front of the driver (below the speed).

After about 1.5 miles it switched back to EV (there is a gauge coloration switch from blue (gas/CS) to green (EV/CD) when that happens, and the warning message popped up every time the ICE kicked on. During that first 1.5 miles the EV range dropped to 23 miles, so at first I thought it might be blending fuels, but I now suspect it was just the algorithm trying to adjust for the actual conditions.

My first 8 miles or so were "surface" suburban roads, around 40-45 mph and plenty of lights. The ICE cycled on 2-3 more times during that phase, each time running for about a minute or so.

I then had about 10 miles on the highway at about 70 mph, it cycled on again 2 more times during that phase. Then my last bit was about 5 miles of "city" type driving and two more cycles.

Total on the 23 mile trip (22.8 in fact), the car displayed 17.6 mi on EV, 5.2 mi on gas, 0.26 gallons used, and 88.4 total mpg. My calculated CS mpg was 20 mpg, much lower than normal CS operation so it must be doing something more than supplying waste heat, because it certainly wasn't charging the battery [arrived at destination with 3 miles EV remaining on the display (20.6 AER with the 17.6 traveled, 3.4 less than originally displayed on start up).

This was the first time this ever happened to me (did not occur in the 20's) so it was pretty fascinating. I'm not real happy with the 20 mpg in CS - heat up mode, but the numbers are what they are. I figured some of you would be interested.

If temperatures stay in the same range tomorrow I will try to experiment with switching to MM for a portion of the ride once displayed AER is less than 14 miles remaining (based on prior experiments I get about 25 mpg while using MM to charge the battery in that condition so it might generate an improvement to just run the ICE more continuosly then see if I still get the cycling on of the ICE when I switch back to EV during the "city" portion of my trip. ("city" is Middletown DE, which has slow stop and go traffic [esp in the mornings] but would probably offend anyone from a real city to be lumped in the same category)