EV Efficiency

[msvphoto]

In reading about my favorite carmaker's (Audi) media drive from Central Valley to Tahoe via Hwy 50 that happened last week the results are both impressive and disappointing. Impressive in that driven like a normal car, climate control on, at reasonably fast highway speeds climbing up the Sierras the eTron did quite well on range and fast charging in Sacramento. It appears Audi did an exceptional job of battery management in the eTron. What was disappointing was the efficiency. 2 miles/kWh average is 3 times as much energy as a certain forum member gets out of his eGolf, and still well over our average since purchase (mid 4s). Maybe the comparison is less than fair. Perhaps under the same conditions an eGolf would only get around 3 miles/kWh, but even then a far more efficient car with only slightly less interior volume.

My thoughts are when will efficiency matter in EVs like it does in ICE cars? It may not matter much when charging at home with EV rates and/or solar panels, but it could when hitting the road and paying premium prices for charging (especially with the new ultra fast DC charging no doubt costing the most to cover charging equipment costs).

I get it that cost per mile doesn't matter much to those spending close to $100k for a car, but it does to some of us. I guess where I am going is despite the low range and less than idea road trip capability, the e-Golf is still viable, efficient, and pleasurable to drive car. My hope is VW doesn't lose track of that in the new MEB platform offerings. Leave the luxury barges and hot sports cars to Porsche and Audi (and Lambo, Bentley, Bugatti) and focus on what VW does best with their future EVs which is push efficiency with driving pleasure.

This all said by the guy who's primary ICE car is a gas sucking BMW V8 (which is currently down for the count with timing chain guide issues ...)

 

[2016golfse]

The 2 mi/kWh efficiency by the E-Tron is no different than if the trip were made by a Model X. The fact of the matter is that battery and body weight, all-wheel drive, speed, and aero contribute to less efficiency. The other fact is that efficiency matters less when the battery is big, which of course drives the price of the vehicle higher and the clientele who end up with said vehicle.

 

[JoulesThief]

Curious if the e-tron was even attempted at being driven for efficiency. Unlikely since Audi has advertised in the past "Driven to Performance". They don't define what their definition of "Performance" is.

However, if it's press related or marketing related, to sell cars, you can bet the least most important performance parameter was efficiency or kWh per 100 km. People interested in that type of performance are not likely to shell out the Audi premium price tag.

It seems crazy how a very, very few spent an enormous amount of money to buy a Volkswagen XL1... so much money for such a small impractical car. https://en.wikipedia.org/wiki/Volkswagen_1-litre_car

 

[msvphoto]

The 2 mi/kWh efficiency by the E-Tron is no different than if the trip were made by a Model X. The fact of the matter is that battery and body weight, all-wheel drive, speed, and aero contribute to less efficiency. The other fact is that efficiency matters less when the battery is big, which of course drives the price of the vehicle higher and the clientele who end up with said vehicle.

I totally get that, and understand the physics. I also personally know one of the media drivers that drove one of the cars, and yes, they were not trying to be efficient. Agreed, a model X would be about the same. It makes me wonder where the EV sweet spot really is in the trade off between battery capacity (read weight) and performance (including efficiency) is. Not sure we really are there yet.

My holy grail EV is still something that drives and handles like the e-Golf but can go 250 miles minimum in all weather conditions with creature comforts turned on doing ~80mph. Probably won't happen in my price range in my lifetime, but I can dream and buy (sometimes a lot of) gas in the meantime.

 

[JoulesThief]

For 80 mph, figure about 3 miles per kwh in an e-Golf. 250 miles / 3 miles per kWh is going to require 85 to 90 kWh battery. Speed kills battery range.

You can look at the same results in light aircraft, the gallons per hour consumption of gas from 80 kts/hr to 120kts/hr to 160 kts/hr, is astronomical. You can't beat drag, it's expensive. Slow down and remove the drag and the power consumption.

 

[HighMR]

Has anyone done a consistent, round trip comparison of driving with different regeneration modes? I am finding that regen 2 feels natural to me, like a stick shift, and B, especially, is too extreme. What kinds of differences in efficiency are possible with careful driving technique?
(my commute is mostly freeway, but speeding up and slowing down due to traffic, so regeneration is important).

Also, has anyone done a consistent, round trip comparison of efficiency impact of replacing the tires with something with more grip, such as UHP all season tires?

 

[JoulesThief]

IMHO... the e-Golf is not a Suburb / city freeway commuter car, that was never it's intent or design, as it doesn't really have enough battery for constant cruising speeds.

I realize I am probably the lone anomaly here, getting 6.0 to 6.3 miles per kWh, but I am also probably the poster child that VW designed the Peoples Car e-Golf for. City commuter crawler / grocery getter / putt putter around town on suburban streets, residents and BlVd cruising at 40 to 45 mph tops. I rarely drive for fun, I drive for utility, to get to point B from point A economically and efficiently.

Efficiently doesn't include long drives doing 80 down the freeway, because the distances traveled are so short as to be insignificant in time savings, due to losses being motionless at timed red lights, stop signs, and heavy traffic on surface streets.

So I accept that I am the anomaly, but again, I've demonstrated enough times, consistently, that the e-Golf does very well at this type and style of travel. Perfect for the stay at home housewife with kids, driving to and from school, grocery shopping, to the mall, to the hair stylist or for a local pedicure. What it probably will never do well is vacation trips. Rent a gas or diesel car for that, instead, if it makes more $ and sense., and you need to do a big road trip to the ski slopes.

Here in Los Angeles, you can do weekend bus trips with a touring company up to Mammoth Mtn and back, leave on friday, come back on Sunday, and leave the driving to them, while you booze and cruise with your ski buddies. Maybe SF or SJ or Sac has similar offers?

 

[HighMR]

IMHO... the e-Golf is not a Suburb / city freeway commuter car, that was never it's intent or design, as it doesn't really have enough battery for constant cruising speeds.

I realize I am probably the lone anomaly here, getting 6.0 to 6.3 miles per kWh, but I am also probably the poster child that VW designed the Peoples Car e-Golf for. City commuter crawler / grocery getter / putt putter around town on suburban streets, residents and BlVd cruising at 40 to 45 mph tops. I rarely drive for fun, I drive for utility, to get to point B from point A economically and efficiently.

Efficiently doesn't include long drives doing 80 down the freeway, because the distances traveled are so short as to be insignificant in time savings, due to losses being motionless at timed red lights, stop signs, and heavy traffic on surface streets.

So I accept that I am the anomaly, but again, I've demonstrated enough times, consistently, that the e-Golf does very well at this type and style of travel. Perfect for the stay at home housewife with kids, driving to and from school, grocery shopping, to the mall, to the hair stylist or for a local pedicure. What it probably will never do well is vacation trips. Rent a gas or diesel car for that, instead, if it makes more $ and sense., and you need to do a big road trip to the ski slopes.

Here in Los Angeles, you can do weekend bus trips with a touring company up to Mammoth Mtn and back, leave on friday, come back on Sunday, and leave the driving to them, while you booze and cruise with your ski buddies. Maybe SF or SJ or Sac has similar offers?

I agree with respect to constant speed cruising. My post was about a commute situation with speeding up and down due to traffic (on the freeway) and due to traffic lights. On a round trip (to equalize up and down hill) I am getting around 4.9 miles/kWh with this situation (limited data so far).

 

[f1geek]

4.9 mi/kWh is pretty good. I have a flat 9 mile commute, including 5 miles of highway driving, typically at 60 mph. I also do a fair amount of local driving. I usually average 5 to 6 mi/kWh, depending on the weather. I just charged my car (4 day interval) and had a 5.8 mi/kWh efficiency for the 90 miles I drove. I charge to 80% routinely and in this current northern California weather, the GOM reads 140 to 145 miles of range at 80% SoC. When I have taken long highway trips (1.5 hour non-stop drive to travel about 95 miles), I typically get around 4.2 to 4.5 mi/kWh. The e-golf is great around town and also a very quiet, comfortable highway cruiser, just as it was designed to be by VW.

 

[Sparklebeard]

I got 4.9mi/kWh from San Jose to Monterey on 101 this weekend with the cruise control set to 65mph and the A/C off.

that was with resetting the ‘since start’ immediately before getting on 101, and taking the reading immediately as I exited the highway, so the average speed was 55mph (a couple of slow downs from traffic, mostly 65mph cruising)

JT may be selling them short by saying these cars are only well suited to city crawling. 80mph cruising may not be its forte, but driving at the 65mph speed limit is a piece of cake.

 

[JoulesThief]

I got 4.9mi/kWh from San Jose to Monterey on 101 this weekend with the cruise control set to 65mph and the A/C off.

that was with resetting the ‘since start’ immediately before getting on 101, and taking the reading immediately as I exited the highway, so the average speed was 55mph (a couple of slow downs from traffic, mostly 65mph cruising)

JT may be selling them short by saying these cars are only well suited to city crawling. 80mph cruising may not be its forte, but driving at the 65mph speed limit is a piece of cake.

I believe there was a very, very distinct reason that VW leased so many 2015 and 2016 e-Golfs with emphasis on 7,500 miles /year leases. They wanted the cars back after 2.5 to 3 years of lease time from beta testers, to gather data on battery life for warranty purposes. That's my belief, VW pushed very hard to get people into those 7500 mile/year lease agreements, with very, very favorable terms for those types of lease.

I'm running very close to 6000 miles /year on my owned 2015 SEL. Just turned 23000 miles today, measured treads... 7/32 front tires, 9/32 rear tires. I guess I am doing something right with how I drive, to see those kind of tread wear patterns.

 

[f1geek]

Great theory, but wrong. VW can get battery life data any time it wants from the Car-net data connection to the car - no need to have the car back. I leased a 2015 with 10,000 miles/year on the lease, and I drove it 27,000 miles in three years. I also believe because VW is such a conservative company that they already knew the battery life expectancy based on extensive testing, thus the 70% capacity warranty. Not all carmakers provide a capacity warranty, and VW needed to get people into cars to meet their CA (and other state) ZEV credits.

 

[JoulesThief]

Great theory, but wrong. VW can get battery life data any time it wants from the Car-net data connection to the car - no need to have the car back. I leased a 2015 with 10,000 miles/year on the lease, and I drove it 27,000 miles in three years. I also believe because VW is such a conservative company that they already knew the battery life expectancy based on extensive testing, thus the 70% capacity warranty. Not all carmakers provide a capacity warranty, and VW needed to get people into cars to meet their CA (and other state) ZEV credits.

Wrong? According only to you! Multicoat White and real Vegan Leather seats in your signature kind of says it all, dancing to the beat of a different drum.

With your theory, there is no need for VW to ever do a battery check at a dealership. Hell they can diagnose CEL's too, no need to pay dealership a $150 diagnosis fee to get a CEL turned off, it's all accessible by Car-Net.

 

[f1geek]

Of course VW Dealers need to perform unnecessary maintenance. VW dealers somehow need to make money off of BEVs because BEVs require so little maintenance compared to fossil gobblers. Also, dealers are independent middlemen who need to take a cut, so if corporate VW did all the work, then dealers might go bankrupt - and that would be truly horrible.

 

[JoulesThief]

Of course VW Dealers need to perform unnecessary maintenance. VW dealers somehow need to make money off of BEVs because BEVs require so little maintenance compared to fossil gobblers. Also, dealers are independent middlemen who need to take a cut, so if corporate VW did all the work, then dealers might go bankrupt - and that would be truly horrible.

There's fossil gobbler electricity being made to recharge electric cars too. You should see how much electricity gets sold from coal sucking power plants running full tilt boogey in Arizona. Don't be so quick to claim your hands are clean of fossil fuels.

 

[Sparklebeard]

Arizona average energy generation break-down (Source)

Natural Gas Fired: 33%
Coal-fired: 21%
Nuclear: 34%
Hydroelectric: 6%
Nonhydroelectric renewable: 6%
Petroleum burning: <0.1%

54% carbon based fuel, but the coal component is fairly low.

according to source, a 2019 VW e-Golf charged in Phoenix AZ emits on average 154g of CO2 per mile. Same car in LA or SF is 83g per mile. In Charleston WV, probably the worst in the country, it’s 180g/mi.

If I calculated correctly from 30mpg rated consumption a Golf TDI would emit on average 333g per mile, everywhere.

you didn’t bring up CO2, just some interesting numbers to consider.

 

[f1geek]

Good point about how low the carbon dioxide emissions of EVs are. I live in a city where we pay for 100% renewable energy (wind and solar) from producers within and outside of California, so my car's carbon emissions per mile is 0 g.

 

[JoulesThief]

Arizona average energy generation break-down (Source)

Natural Gas Fired: 33%
Coal-fired: 21%
Nuclear: 34%
Hydroelectric: 6%
Nonhydroelectric renewable: 6%
Petroleum burning: <0.1%

54% carbon based fuel, but the coal component is fairly low.

according to source, a 2019 VW e-Golf charged in Phoenix AZ emits on average 154g of CO2 per mile. Same car in LA or SF is 83g per mile. In Charleston WV, probably the worst in the country, it’s 180g/mi.

If I calculated correctly from 30mpg rated consumption a Golf TDI would emit on average 333g per mile, everywhere.

you didn’t bring up CO2, just some interesting numbers to consider.

I don't know how you got 30 mpg rated consumption for a Golf TDI. You can see my actual consumption, for every fill up, for the past 18 months, here for my much larger and heavier 2015 Passat TDI SEL. yourhttp://www.fuelly.com/car/volkswagen/passat/2015/magalicious/750468

My Touareg Lux TDI that's AWD and 5000 # does what the golf TDI you picked, claims.
http://www.fuelly.com/car/volkswagen/touareg/2014/magalicious/824181

So, now you have some real world numbers to compare against the e-Golf. Closer to 200-220 gms per mile. Now lets also consider that C02 is made from Oxygen, molecular weight of 16, x 2, because there is 2 parts to is, or 32 grams, ALREADY EXISTING in the atmosphere before the fuel was burned, and 12 grams actually ADDED of carbon weight, to the atmosphere, by petroleum fuel being burned. That's 12 grams /44 grams or 27.27% or your 333 grams, or my 210 grams actual, per mile, or 57.3 grams of Carbon added per mile.

Using weight of CO2 when the oxygen is the heavy part of the equation is false math and false science and false claims about the WEIGHT of CARBON added to the atmosphere, the weight of the Oxygen is never added, it was already there in existence, and used to oxidize the carbon to make energy during the chemical bonding process.

 

[Sparklebeard]

I don't know how you got 30 mpg rated consumption for a Golf TDI. You can see my actual consumption, for every fill up, for the past 18 months, here for my much larger and heavier 2015 Passat TDI SEL. yourhttp://www.fuelly.com/car/volkswagen/passat/2015/magalicious/750468

My Touareg Lux TDI that's AWD and 5000 # does what the golf TDI you picked, claims.
http://www.fuelly.com/car/volkswagen/touareg/2014/magalicious/824181

So, now you have some real world numbers to compare against the e-Golf. Closer to 200-220 gms per mile.

Answering this in two parts, and addressing this first.

You're right, I made a mistake. the official EPA rating for the 2015 Golf TDI Automatic is 35mi combined cycle, not 30. According to the EPA, a gallon of diesel burns to produce 10,180g of CO2. That makes for 290g/mi.

Hopefully this link works, it should bring up a comparison between 2015 e-Golf, Golf TDI, and Passat TDI


Your measured fuel consumption is much better than that. But lets also consider that the eGolf's EPA rated efficiency is a combined cycle 3.4mi/kWh and that we have been reminded that you see 6-6.6mi/kWh in your e-Golf. So for the sake of numbers here, lets take a deeper dive. So at 3.4mi/kWh in California, the e-Golf produces 83g/mi, which tells us that a kWh in California expended by the car effectively emits 282.2g. Following from this, assuming 6mi/kWh, on the lower end of your reported efficiency, you're only emitting 47g/mi, which is 56% of the average rated emission
Your real-world 46.5mpg for the Passat have you emitting 215g/mi, the EPA rated 33mpg has it emitting 303g/mi. Your emissions are 71% of it's rated emissions. This seems pretty comparable with the delta between rated and actual fuel consumption on your e-Golf, especially when you consider that ICE are inherently less efficient, thus there's a smaller margin of efficiency gain to be found through driving style.

It should not come as a surprise to you that if your driving style in your e-Golf gets your significantly better efficiency than the rated efficiency, you would also exceed the rated efficiency in your diesel.

This is why the numbers being compared are all EPA's official combined rating, since (in theory) it's supposed to try to be as directly comparable between vehicles as possible, even if the number on the rating isn't the number you should personally expect to see on the vehicle.

Now lets also consider that C02 is made from Oxygen, molecular weight of 16, x 2, because there is 2 parts to is, or 32 grams, ALREADY EXISTING in the atmosphere before the fuel was burned, and 12 grams actually ADDED of carbon weight, to the atmosphere, by petroleum fuel being burned. That's 12 grams /44 grams or 27.27% or your 333 grams, or my 210 grams actual, per mile, or 57.3 grams of Carbon added per mile.

Using weight of CO2 when the oxygen is the heavy part of the equation is false math and false science and false claims about the WEIGHT of CARBON added to the atmosphere, the weight of the Oxygen is never added, it was already there in existence, and used to oxidize the carbon to make energy during the chemical bonding process.

Now this is where we are going to have a problem.

Do NOT accuse me of "false math and false science and false claims" if you plan to immediately follow it up with something as false as what you just said.

Literally no one is concerned about the mass of carbon atoms being added to the atmosphere, which is what you've sneakily tried to make the conversation about by inexplicably talking about the atomic mass of carbon and oxygen. Neither carbon atoms nor molecular oxygen are greenhouse gases of concern, but once you combine them, the resulting molecule is. It does not matter one iota for this discussion where those oxygen molecules came from because they weren't acting as a greenhouse gas. We need to measure the amount of carbon dioxide molecules added to the atmosphere, though, so we need some sort of unit to measure that and given that CO2 molecules have a consistent mass per molecule, grams is the sensible way to measure it.. Methane and CO2 have the exact same mass of carbon per molecule, but methane is an even more potent greenhouse gas. Explain to me why measuring just the carbon atoms makes any sense?

One thing that I think you failed to consider before writing that up; if we are only measuring the grams of carbon atoms added to the atmosphere by the diesel car, then we would also have to only measure the grams of carbon atoms added to the atmosphere by the electric cars, so proportionally the numbers are identical!

Basing it off the official EPA combined rating:

Using grams of CO2
e-Golf 83g CO2 / mi (28.6% of the TDI)
Golf TD. 290g CO2 / mi

Using grams of C (assuming your 27.27% conversion factor is correct)
e-Golf 22.6g C / mi (28.6% of the TDI)
Golf TDI 79g C / mi

:lol: :lol: :lol:

 

[JoulesThief]

I don't know how you got 30 mpg rated consumption for a Golf TDI. You can see my actual consumption, for every fill up, for the past 18 months, here for my much larger and heavier 2015 Passat TDI SEL. yourhttp://www.fuelly.com/car/volkswagen/passat/2015/magalicious/750468

My Touareg Lux TDI that's AWD and 5000 # does what the golf TDI you picked, claims.
http://www.fuelly.com/car/volkswagen/touareg/2014/magalicious/824181

So, now you have some real world numbers to compare against the e-Golf. Closer to 200-220 gms per mile.

Answering this in two parts, and addressing this first.

You're right, I made a mistake. the official EPA rating for the 2015 Golf TDI Automatic is 35mi combined cycle, not 30. According to the EPA, a gallon of diesel burns to produce 10,180g of CO2. That makes for 290g/mi.

Hopefully this link works, it should bring up a comparison between 2015 e-Golf, Golf TDI, and Passat TDI


Your measured fuel consumption is much better than that. But lets also consider that the eGolf's EPA rated efficiency is a combined cycle 3.4mi/kWh and that we have been reminded that you see 6-6.6mi/kWh in your e-Golf. So for the sake of numbers here, lets take a deeper dive. So at 3.4mi/kWh in California, the e-Golf produces 83g/mi, which tells us that a kWh in California expended by the car effectively emits 282.2g. Following from this, assuming 6mi/kWh, on the lower end of your reported efficiency, you're only emitting 47g/mi, which is 56% of the average rated emission
Your real-world 46.5mpg for the Passat have you emitting 215g/mi, the EPA rated 33mpg has it emitting 303g/mi. Your emissions are 71% of it's rated emissions. This seems pretty comparable with the delta between rated and actual fuel consumption on your e-Golf, especially when you consider that ICE are inherently less efficient, thus there's a smaller margin of efficiency gain to be found through driving style.

It should not come as a surprise to you that if your driving style in your e-Golf gets your significantly better efficiency than the rated efficiency, you would also exceed the rated efficiency in your diesel.

This is why the numbers being compared are all EPA's official combined rating, since (in theory) it's supposed to try to be as directly comparable between vehicles as possible, even if the number on the rating isn't the number you should personally expect to see on the vehicle.

Now lets also consider that C02 is made from Oxygen, molecular weight of 16, x 2, because there is 2 parts to is, or 32 grams, ALREADY EXISTING in the atmosphere before the fuel was burned, and 12 grams actually ADDED of carbon weight, to the atmosphere, by petroleum fuel being burned. That's 12 grams /44 grams or 27.27% or your 333 grams, or my 210 grams actual, per mile, or 57.3 grams of Carbon added per mile.

Using weight of CO2 when the oxygen is the heavy part of the equation is false math and false science and false claims about the WEIGHT of CARBON added to the atmosphere, the weight of the Oxygen is never added, it was already there in existence, and used to oxidize the carbon to make energy during the chemical bonding process.

Now this is where we are going to have a problem.

Do NOT accuse me of "false math and false science and false claims" if you plan to immediately follow it up with something as false as what you just said.

Literally no one is concerned about the mass of carbon atoms being added to the atmosphere, which is what you've sneakily tried to make the conversation about by inexplicably talking about the atomic mass of carbon and oxygen. Neither carbon atoms nor molecular oxygen are greenhouse gases of concern, but once you combine them, the resulting molecule is. It does not matter one iota for this discussion where those oxygen molecules came from because they weren't acting as a greenhouse gas. We need to measure the amount of carbon dioxide molecules added to the atmosphere, though, so we need some sort of unit to measure that and given that CO2 molecules have a consistent mass per molecule, grams is the sensible way to measure it.. Methane and CO2 have the exact same mass of carbon per molecule, but methane is an even more potent greenhouse gas. Explain to me why measuring just the carbon atoms makes any sense?

One thing that I think you failed to consider before writing that up; if we are only measuring the grams of carbon atoms added to the atmosphere by the diesel car, then we would also have to only measure the grams of carbon atoms added to the atmosphere by the electric cars, so proportionally the numbers are identical!

Basing it off the official EPA combined rating:

Using grams of CO2
e-Golf 83g CO2 / mi (28.6% of the TDI)
Golf TD. 290g CO2 / mi

Using grams of C (assuming your 27.27% conversion factor is correct)
e-Golf 22.6g C / mi (28.6% of the TDI)
Golf TDI 79g C / mi

:lol: :lol: :lol:

I'm totally fine with greenhouse gasses.

It favors plant life, flora, over animal life, fauna.

Not a surprise with all the destruction over population of humans has done to this planet, including higher standards of living, obesity and healthcare, causing humans to live longer, doing more damage, instead of normal shorter life cycles and higher turnover rates. I just don't see anyone volunteering wanting to jump off the planet or otherwise lowering the biomass of humans here on earth. IMHO, that's what it needs. Less people, less cars, less transportation needs to get to work. Maybe live where you work, and leave where you live on weekends, to cut down on pollution. Just watching the pie get smaller and smaller for everyone.

How much CO2 could we eliminate if half the world population got the Bubonic plague and died within 2 or 3 years?