BYD's All-Electric e6: Will It Be A Game Changer In The U.S. Market?

  • Thread starter Pengwuino
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In summary: The Chevy Volt's "230 mpg"?The new Chevy Volt is expected to get a 230mpg city rating. After reading up on it, the Volt's charge time and fuel efficiency are still being questioned. Chevy is currently being ridiculed all over the net for this claim. The Volt's "230 mpg" claim is only accurate if the car is driven continuously and the miles driven are multiplied by 50.
  • #36


Kenneth Mann said:
BTU and Kilowatt are not equivalent! On the other hand, any attempt to intermingle battery efficiencies and gasoline efficiency equivalencies for a serial hybrid are meaningless.

KM

you're right, and i should have said kilowatt-hours or kilojoules, etc.

so you agree that the 250 mpg number is meaningless?
 
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  • #37


Pengwuino said:
Now there's the problem, that's miles traveled continuously. The ideal situation is you drive to work, run some errands, come home, plug back in, all hopefully within that first 40 miles of pure electricity and you effectively divide by zero. The Volt violates the laws of math!

It's not zero. EPA assigns a "gallons" equivalent to a Watt-Hour of energy.

KM
 
  • #38


junglebeast said:
If they want to advertise better gas mileage, they should do it honestly: it is 40 free miles + 50 mpg after that. Saying that it has 230 miles per gallon is flat out lying, and should make them liable to class action lawsuit IMO.

Their method is perfectly honest - - it just considers the car as a battery electric, rather than a hybrid - - and it is really designed as a battery electric - - with a back-up mode as a hybrid, so you won't get stranded.

KM
 
  • #39


So if 230miles = 1 gallon = 8.8Kg CO2 = $3

Each charge = 40miles = 9kWh = $1
So 230miles = 5.7charges = 52 kwH = $5.7
average CO2 from grid = 0.6kg/kwh or 1kg/kWh from coal
52Kwh = 230mi = 30 - 50 kg CO2 depending on source

Can't see where they get 230mpg from
 
  • #40


The Volt is far more efficient as an electric than it is as a hybrid.

KM
 
  • #41


mgb_phys said:
It's only in the US that city/highway figures are even quoted or used by consumers - in Europe where gas costs $8-10/gallon nobody reads them, you just look at the engine size. You know if you bought a 3.5L BMW you aren't going to care about the cost of gas, if you are worried you buy the 1.2L Lupo instead of the 1.4L Golf - if you buy the 1L Citroen diesel your main worry is forgetting where the filler cap is when you do run out.

I think people who do manage to just use a hybrid over it's plugin range are going to be very happy about the cost.

And this would make the Volt much better suited for Europe (and Japan) than for America (or China). Still, it would suit a lot of people in the US and China too.
 
  • #42


Ivan Seeking said:
The fact is that the increased cost of the plug-in over a standard fuel-efficient vehicle is more than the lifetime cost of fuel for the latter.

With a unit production cost to GM of about $35,000, suggesting a sales price of about $40K, at least for now, this car is way too expensive to be of any practical value. It is a novelty for yuppies.

And this is the car's biggest drawback. On the other hand, GM admits that the production costs will drop. They should probably do what Toyota did with the early Prius, and sell it at cost. This would drop the cost to about $27,500 with the anticipated $7500 Government rebates. It would probably increase sales considerably and help make the car viable sooner (or even be the deciding factor).

KM
 
  • #43


Ivan Seeking said:
I wasn't dissing the approach, just the current product. Very few people are going to buy a $35,000 [after federal tax credit] Corolla.

Of course, effectively lying about the mileage and saying it gets 230mpg will help for a short time - a wow factor for the suckers.

They are not lying! They are just using EPA formula for the case in which the car is driven as an all-electric.

KM
 
  • #44


Ivan Seeking said:
I would phrase it differently: It is a matter of betting on which technology will be cost effective first; biofuel technologies, or batteries for electric cars?

Diesel cars are a proven technology - a great option ready to go. Electric motors are already 90%+ efficient, though too expensive. But the race ultimately becomes one of biodiesel vs batteries. Biodiesel from food crops is a competitive option at about $3 per gallon, but we could never produce enough to supply the entire US petro market. It also puts food into direct competition with energy. The key to practical, carbon-neutral fuel sources will be second generation biodiesel fuel sources - fuel obtained from algae or other organisms - or third generation sources such as bioengineered algae or bacteria, not food crops

To the best of my knowledge, the limits on battery technology are fundamental. Advances in battery technology may or may not follow a similar price/capacity curve as we saw with integrated circuit technology. Such a curve is implied anecdotally, but we don't know when we will see the next significant advances or how significant they will be. While we may see great advances in the future, it is also conceivable that we are approaching a limit and the next great advances will never come.

With advanced fuel technologies, the limits seem to be more a matter of engineering and applied biology, and not a matter of making fundamental advances. Therefore, I think the most logical bet is to drive towards advanced fuel technologies and the use of clean diesel cars over the next ten years. There is already plenty of impetus in the market to incentivize advances in battery technologies, so allow that to drive the electric car option rather than driving it artificially.
While I feel the argument for the EV is stronger, your post is one of the better articulated one page comparisons of the two competitors I've seen lately, and there are many lesser ones to see.

Meanwhile, the advanced fuel technologies needed to end our reliance on petroleum completely - something not even conceivably possible at this time with electric technologies - seem to be well within our grasp now.

Biodiesel or related products [pure oils] can be used to power all forms of transportation - cars and trucks, heavy trucks, trains, ships, and aircraft - as well being compatiable with heavy industrial needs such as cranes, generating stations, etc.
This part is particularly interesting so two responses here.

First I'd argue that the problem with a 100% biofuel replacement of petroleum is that at current efficiencies of the transportation fleet biofuel crops can't handle the demand without causing more problems along the way. I'm not inclined to rerun the miles/perBTU/per acre game one more time here; but I'll go ahead and suggest that BF at that scale requires too much land and water, inevitably displacing good land in use for something else. Now here's the big caveat: a BF takeover can work in a BTU sense if the efficiency of transportation goes up by 2 to 3x, which takes us back around to replacement of the internal combustion engine w/ the electric motor.

Regards the limitations of which transportation type can or can not conceivably be run by an electric motor: I am not aware of any that can not. The last one I could think of was jet travel, and now even that appears doable with HTS electric ducted fans. It's a reach, but certainly conceivable and NASA and the AF are pursuing. Powering the electric motors of theoretical long distance jet aircraft or long distance trains from electro chemical batteries is not doable at current energy densities, but that gets back to your point about fundamental limits.
 
  • #45


from an article on gm-volt.com

Here’s my guess:

Mike Duoba from Argonne National Lab devised a method to determine the MPG of an EREV; first the car is driven from a full battery until it reaches charge-sustaining mode, then one more cycle is driven. If we use the highway schedule, the first 40 miles are electric. One more cycle is 11 more miles. If the Volt gets 50 MPG in charge sustaining mode, it will use .22 gallons of gas for that 11 miles. Thus 51 miles/.22 gallons = 231.8 MPG.
 
  • #46


junglebeast said:
No matter how fuel efficient these new cars are, they aren't going to be economically practical in comparison to buying a crappy old used car that gets average gas mileage. I can only assume they are trying to appeal to the environmentally conscious baby boomer generation who doesn't mind paying extra for a new car to do their part in helping the environment by using less gas. It will take a decade for these new cars to be cheap cars on the used market, but probably they will be in such short supply (as used cars) that they will be more expensive than other used cars of the same age (my guess)...and we may have to wait 20 or more years before hybrids and electrics actually start to become affordable as used cars for college students and the like.

Don't forget Obama. He probably has a few surprises ready for those of us with old guzzlers. We've already seen the carrot - - is the stick coming?

KM
 
  • #47


mgb_phys said:
If we assume 9kWh/40miles for the Volt.
A US coal fired power station produces about 1kg CO2/kWh.
So 40miles = 1 charge = 9kg CO2
A gasoline engine releases about 2.2Kg CO2 / litre = 18.3 kg CO2/gallon(US)
So if it does 50mpg, it is about 2x as much CO2 on gas as on plugin


A unit of electric costs around 10c, so around $1 per 40mi charge, 40miles on ICE would take around 1 gallon = $2-3 ?
I think that's the answer to how the government is going to need to start mandating ratings. All cars should have a sticker on them with the following information:

-Fuel capacity in kwh (if there are two fuels, list them separately)
-Average range in total and by fuel individually
-Divide one by the other and you get fuel economy in miles per kwh
-Then in big, bold letters, the bottom line: $$ per mile for each fuel and combined, for city and highway.
 
  • #48


Kenneth Mann said:
Your comparison is incorrect! The 230 figure is derived for the case for which the car is driven entirely on its charge, and the gasoline consumption is zero - - perfectly valid for people who drive no further than 40 miles each day and recharge every night while they sleep. This makes sense for a lot of city folks.

KM

They are not lying! They are just using EPA formula for the case in which the car is driven as an all-electric.
No they aren't. Though it is speculative because GM didn't say how they reached it exactly, it is believed they did a lot with the battery and a little with the gas engine:
It was not immediately clear how GM reached the 230 mpg in city driving, but industry officials estimated the automaker's calculation took into consideration the Volt traveling 40 miles on the electric battery and then achieving about 50 mpg when the engine kicked in.
http://news.yahoo.com/s/ap/20090811/ap_on_bi_ge/us_gm_volt_mileage [Broken]
 
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  • #49


russ_watters said:
I think that's the answer to how the government is going to need to start mandating ratings. All cars should have a sticker on them with the following information:

-Fuel capacity in kwh (if there are two fuels, list them separately)
-Average range in total and by fuel individually
-Divide one by the other and you get fuel economy in miles per kwh
-Then in big, bold letters, the bottom line: $$ per mile for each fuel and combined, for city and highway.
Exactly
 
  • #50


russ_watters said:
I think that's the answer to how the government is going to need to start mandating ratings. All cars should have a sticker on them with the following information:

-Fuel capacity in kwh (if there are two fuels, list them separately)
-Average range in total and by fuel individually
-Divide one by the other and you get fuel economy in miles per kwh
-Then in big, bold letters, the bottom line: $$ per mile for each fuel and combined, for city and highway.

For the Volt:
1) miles per kwh equivalent to 40 mpg running on ICE.
2) miles per kwh equivqlent to 230 mpg when running on battery
3) when taken together - - hopeless -- because Volt doesn't have a consistent
duty cycle like the other hybrids.

KM

I placed about 15 insertions yesterday, but when it was finished the count was the same as when I started. Why?
 
  • #51


Kenneth Mann said:
I placed about 15 insertions yesterday, but when it was finished the count was the same as when I started. Why?

If you're referring to your post count, then GD and forum feedback do not contribute to it.
 
  • #52


Kenneth Mann said:
For the Volt:
2) miles per kwh equivqlent to 230 mpg when running on battery
Again, that's not what is apparently being claimed. The link I posted and the analysis someone else did imply that that is gas consumption while running in a mostly electric mode.
3) when taken together - - hopeless -- because Volt doesn't have a consistent
duty cycle like the other hybrids.
The EPA will just have to make a standard and have car companies stick to it. They already have a driving course for city and highway driving for other cars, so there is no reason they can't set up a similar standard for hybrids/plug-ins.

Perhaps to reflect the fact that people who commute tend to commute less than 40 miles a day, they will need to add another couple of data points, for "city commute" and "highway commute".

Or perhaps they could even do a customize fuel economy report for everyone. Fill out an online questionaire about your driving habits and it could give you your predicted fuel economy with different cars.
 
  • #54
Kenneth Mann said:
For the Volt:
1) miles per kwh equivalent to 40 mpg running on ICE.
GM claims 50 mpg.
The generator is small, 70HP, running near constant RPM, so 50 mpg is doable.
http://gm-volt.com/chevy-volt-faqs/
 
  • #55


Kenneth Mann said:
For the Volt:
2) miles per kwh equivqlent to 230 mpg when running on battery
You do not want to do that 'mpg' 'equivalent' bit on the battery. Its hopelessly misleading. Can you travel 230 continuous miles with one gallon in the tank? No. On batteries then? No. Does the gallon of gas cost the same as the same equivalent energy placed in the battery from a wall plug? No.
 
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  • #56


It occurs to me that GM knows full well their recent release of the '230 mpg' figure would be controversial, confusing, and would be challenged. I also believe that's exactly what they want. They need people to start talking about this car, to get this very new thing into the daily discussion. We've been obliging them nicely.:uhh: More than a few people will try out controversial new things, but very few people will try out something they've little or never heard of.
 
  • #57


mheslep said:
You do not want to do that 'mpg' 'equivalent' bit on the battery. Its hopelessly misleading. Can you travel 230 continuous miles with one gallon in the tank? No. On batteries then? No. Does the gallon of gas cost the same as the same equivalent energy placed in the battery from a wall plug? No.

Maybe there is desire not to do that by some - - it is done - - by EPA. It is obviously confusing, judging from the confusion that has occurred in this string - - but it is perfectly valid. There is no general derivational relationship to MPG (equivalent or not) that requires driving a certain number of miles. Battery capacity of the Volt limits its 230 MPG capability to 40 miles. After that, economy drops to 50 MPG (using gasoline).

KM
 
  • #58
mheslep said:
GM claims 50 mpg.
The generator is small, 70HP, running near constant RPM, so 50 mpg is doable.
http://gm-volt.com/chevy-volt-faqs/

Thanks, I didn't check it.

KM
 
  • #59


Just to hint at how confusing the equivalent mileage can be, if both battery and gasoline economies are combined, I've figured a few examples. The only quick-and-easy cases are those of runs of under forty (40) miles, for which cases, the economy will always be 230 (equivalent)MPG. Once the travel goes over 40 miles (approximately), the MPG gets incrementally lower.

Take, for example, a travel of 50 miles from start (full charge):
For the first 40 miles, we get:
40 Mi/230 MPG = 0.1739 Gal (equivalent)
For the next 10 miles, we get:
10 M/50 MPG = 0.2 Gal
For the full 50 miles:
50 M/0.3739 Gal = 133.7 MPG

For a 60 mile run from start:
60M / .5739 Gal = 104.5 MPG

For a 90 mile run from start:
90M / 1.1739 Gal = 76.6 MPG

For a 240 mile run from start:
240M / 4.1739 Gal = 57.5 MPG

I hope this gives some idea of what to expect from the Volt. Obviously unless you average nearly 250 miles driven per day, the turbo diesel won't beat it in economy (until someone puts out a serial hybrid turbo diesel).
The Prius simply won't match it in economy.

KM
 
  • #60


Kenneth Mann said:
Just to hint at how confusing the equivalent mileage can be, if both battery and gasoline economies are combined, I've figured a few examples. The only quick-and-easy cases are those of runs of under forty (40) miles, for which cases, the economy will always be 230 (equivalent)MPG. Once the travel goes over 40 miles (approximately), the MPG gets incrementally lower.

Take, for example, a travel of 50 miles from start (full charge):
For the first 40 miles, we get:
40 Mi/230 MPG = 0.1739 Gal (equivalent)
For the next 10 miles, we get:
10 M/50 MPG = 0.2 Gal
For the full 50 miles:
50 M/0.3739 Gal = 133.7 MPG

For a 60 mile run from start:
60M / .5739 Gal = 104.5 MPG

For a 90 mile run from start:
90M / 1.1739 Gal = 76.6 MPG

For a 240 mile run from start:
240M / 4.1739 Gal = 57.5 MPG

I hope this gives some idea of what to expect from the Volt. Obviously unless you average nearly 250 miles driven per day, the turbo diesel won't beat it in economy (until someone puts out a serial hybrid turbo diesel).
The Prius simply won't match it in economy.

KM

You used their 230 mpg figure, which is questionable.

From previous calculations, I assume 27% efficiency for an internal combustion engine from fuel to axle. For Lithium polymer batteries, 67% efficiency from plug to axle. Use your own numbers for cost of the electric utility and gasoline, to find an mpg equivalent. I would go 10c per KWHr and $320 per gallon. You might have better numbers.
 
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  • #61
mheslep said:
http://gm-volt.com/chevy-volt-faqs/

Check out the last item in that faq:
Q: Will tall people fit in it?
A: Bob Boniface, chief of Volt design says the car is being designed to accommodate drivers from 5th percentile females up to 95th percentile height males.

So the car will accommodate 95% of women and only 5% of men? That means the car would be marketed primarily for single women. Or am I misinterpreting this statement?
 
  • #62


Redbelly98 said:
Check out the last item in that faq:So the car will accommodate 95% of women and only 5% of men? That means the car would be marketed primarily for single women. Or am I misinterpreting this statement?

I interpret that to be: the car will fit all but the shortest 5% of women, and all but the tallest 5% of men.
 
  • #63


That's a height range. A 5th percentile female is near the shortest and a 95th percentile male is near the tallest. In other words, it will fit 95% of all people.
 
  • #64


lisab said:
I interpret that to be: the car will fit all but the shortest 5% of women, and all but the tallest 5% of men.

russ_watters said:
That's a height range. A 5th percentile female is near the shortest and a 95th percentile male is near the tallest. In other words, it will fit 95% of all people.

Okay, that makes sense. :slappinghead: Thanks to you both.
 
  • #65


russ_watters said:
Again, that's not what is apparently being claimed. The link I posted and the analysis someone else did imply that that is gas consumption while running in a mostly electric mode.

I don't know what this "mostly electric" mode is. The Volt is a serial hybrid, and as such should either operate as "all from battery" or from "electricity generated" from the gasoline. I suppose that the system could operate from electricity coming from both the generator and the battery, but what would be the point of this? This would simply reduce the overall efficiency from that gained if running totally from battery. The only purpose of this would be either to make up for the inadequacy (current capacity) of running from battery - - or to obfuscate the true operational cost (by ignoring that derived from battery - - a cynical assumption).

KM
 
  • #66


russ_watters said:
The EPA will just have to make a standard and have car companies stick to it. They already have a driving course for city and highway driving for other cars, so there is no reason they can't set up a similar standard for hybrids/plug-ins.

Perhaps to reflect the fact that people who commute tend to commute less than 40 miles a day, they will need to add another couple of data points, for "city commute" and "highway commute".

Or perhaps they could even do a customize fuel economy report for everyone. Fill out an online questionaire about your driving habits and it could give you your predicted fuel economy with different cars.

Good luck! (Now I'm being cynical, but this just doesn't seem likely.)

KM
 
  • #67


Phrak said:
You used their 230 mpg figure, which is questionable.

Why do you question it? If the number came from Honda would you question it? If it is incorrect, approximately what should it be, and why.

KM
 
  • #68


mheslep said:
While I feel the argument for the EV is stronger, your post is one of the better articulated one page comparisons of the two competitors I've seen lately, and there are many lesser ones to see.

This part is particularly interesting so two responses here.

First I'd argue that the problem with a 100% biofuel replacement of petroleum is that at current efficiencies of the transportation fleet biofuel crops can't handle the demand without causing more problems along the way. I'm not inclined to rerun the miles/perBTU/per acre game one more time here; but I'll go ahead and suggest that BF at that scale requires too much land and water, inevitably displacing good land in use for something else. Now here's the big caveat: a BF takeover can work in a BTU sense if the efficiency of transportation goes up by 2 to 3x, which takes us back around to replacement of the internal combustion engine w/ the electric motor.

That is why, imo, the majority of biofuel will be produced using closed, salt-water algae systems: No competition for land or fresh water, and plenty of water. Not to mention that the ocean [or lakes when appropriate] can be used to provide natural temperature regulation, which has a high energy and or financial cost for many land-based designs. It also removes the cost of land, which is significant to the final cost of the fuel produced.

As for ideas like an electric 797, while it may be possible one day, I think we are a long way from that one. When I have a practical and cost effective electric car, we can talk. :biggrin:

The latest news about algae.
http://www.exxonmobil.com/corporate/files/news_pub_algae_factsheet.pdf [Broken]
 
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  • #69


Kenneth Mann said:
I don't know what this "mostly electric" mode is.
Probably should have said "mostly in electric mode". Ie, 40 miles on battery, 10 miles on the engine.
 
  • #70


Kenneth Mann said:
Why do you question it? If the number came from Honda would you question it? If it is incorrect, approximately what should it be, and why.

KM

The energy content of gasoline is about 34 KWhrs per US gallon.
 

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