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

[russ_watters]

If the tractive load on the electric motor is, say, ~70HP (neglecting losses) from a slight grade or acceleration demand, then the vehicle meets the demand of the driver and the battery is not further depleted with the ICE running at full power.

If the vehicle is climbing a major hill as you described, then let us say the electric motor has to draw ~150HP to climb it, and it will deplete the battery at rate of 80HP down below 30% of full charge for the time to climb the hill. The vehicle controller has some programmed limit as to how long it will allow that to happen before it says no more and forces the power supplied to the motor back to down to 70HP. It will not allow the battery to ever reach full discharge, or anywhere close to that.

And that's my question: what is that performance like, when the car is running as a direct gas-electric? In a regular car, it is my understanding that you lose something like 35% of your power via the drivetrain. So that would mean a 70 hp engine can put 70*.65=45.5 hp to the ground. How much horsepower can the volt put to the ground in this mode? Possible sample calc:

Gas engine drivetrain loss: 10% (I'm assuming a gearbox and clutch).
Generator efficiency: 95%
Power conversion efficiency: 95%
Electric motor efficiency: 95%
Electric motor to wheel drivetrain loss: 10%

Resultant horsepower to the ground: 70*.9*.95*.95*.95*.9=48.6 hp.

I think people are going to want to know what that performance is actually like, lest they find themselves unpleasantly surpised when they suddenly can't go more than 35 mph on a moderately graded highway in the poconos.

Incidentally, a couple of years ago I went on a trip from PA to WV to see a WVU football game and my buddy's Saturn could not maintain highway speed on the interstate on the way there. He had to drop a gear and run at around 55 mph. My Mazda 6i, with 160 hp (but a much bigger car than a Saturn or a Volt) is marginal on similar roads in PA (I can keep 70 mph, but have to do it in 4th gear).

 

[Mech_Engineer]

I'm curious about what caused the diesel price premium last year - ~20% over gasoline. Seems to be gone now.

I'm not sure what caused that spike. From what I understand diesel prices tend to rise in the winter (due to higher heating oil demand) and fall in the summer, but I'm not sure what other drivers affect diesel pricing.

I'm not sure how relevant the comparison is, but I've driven a 92 horsepower Eagle Talon that could eventually wind itself up to over 100 mph (no torque) but couldn't handle any kind of hill and a 75 (I think) horsepower diesel VW Rabbit that was light and had a lot of torque, but still could barely get up to highway speed.

Our diesel Jetta has 100hp (but more importantly 200ft-lbs of torque) and is able to easily maintain 75 or even 65 mph on a 10% grade in 6th gear. It's no slouch in acceleration IMO either (0-60 is around 9 seconds I think) and can get to 100mph no problem. Overall it's very zippy in highway driving and passing situations. Of course you don't get maximum mileage when you're flooring it though...

My point is that it takes more than horsepower to determine driving performance...

 

[Kenneth Mann]

Here are a few more articles on the volt, etc.

KM

http://gm-volt.com/2009/08/11/chevy-volt-gets-230-mpg-city-epa-rating/"
http://gm-volt.com/2009/08/13/gm-still-claims-volt-will-get-40-all-electric-miles-both-highway-and-city-but-under-what-conditions/"
http://gm-volt.com/2009/04/24/the-chevy-volts-electric-range-is-40-miles-in-both-highway-and-city-driving/"
http://gm-volt.com/2007/10/22/under-what-conditions-is-the-chevy-volts-quoted-40-mile-electric-range-modelled/"
http://gm-volt.com/2009/07/08/driving-the-mini-e-electric-car-the-first-1200-miles/"
http://gm-volt.com/2009/05/08/gm-planning-all-electric-city-car/"
http://gm-volt.com/2009/07/31/report-mitsubishi-confirms-it-will-launch-extended-range-electric-car-in-2010/"
http://gm-volt.com/2007/12/07/is-tesla-planning-to-build-an-e-rev-too/"

 

[mheslep]

And that's my question: what is that performance like, when the car is running as a direct gas-electric? In a regular car, it is my understanding that you lose something like 35% of your power via the drivetrain. So that would mean a 70 hp engine can put 70*.65=45.5 hp to the ground. How much horsepower can the volt put to the ground in this mode? Possible sample calc:

Gas engine drivetrain loss: 10% (I'm assuming a gearbox and clutch).
Generator efficiency: 95%
Power conversion efficiency: 95%
Electric motor efficiency: 95%
Electric motor to wheel drivetrain loss: 10%

Resultant horsepower to the ground: 70*.9*.95*.95*.95*.9=48.6 hp.

I think people are going to want to know what that performance is actually like, lest they find themselves unpleasantly surpised when they suddenly can't go more than 35 mph on a moderately graded highway in the poconos.

I think you're mostly right about the loss assumptions. I'd drop possibly the gear/clutch on the gas engine - as the generator should be able to take whatever the engine cares to put out, at a pace the engine likes, and add another 5% power conversion loss going in/out of the battery.

The combustion engine power delivered to the ground, whatever it is, is sufficient to climb a 6% grade continuously at 'reasonable speed' (inferring from the http://www.norkarecreation.com/ride542/Graphics/updatedprofile.jpeg" in Ca statement by GM above). The Volt will climb steeper still by temporarily depleting the battery below its 'sustain' point, but that can't last long (couple minutes?)

Another way to think about the Volt is to imagine a regular combustion engine vehicle with a 150HP motor, but with only enough gas in the tank to go about 45 miles. Once you hit 40 miles, further imagine someone starts slowly trickling more gas into the tank, with the trickling rate such that with average driving one can go another couple hundred miles. At any time you can, if you like, stomp on it but if you keep your foot down you'll get ahead of the trickle.

 

[OmCheeto]

Yes. The Baker Hill scenario makes sense. Though one thing that went through my mind yesterday was the actual output of the 70 hp engine. Few engines are run at full power continuously. Those that are, have fairly short lifespans: outboard motors, indy racers, etc. I would imagine that the ICE would actually only be required to generate a few hp during daily, non-Pikes Peak Rally, back and forth to work treks. So a 70 hp engine does make sense. Though I think they should offer a 20 hp option for people in Kansas. Or maybe 21 hp if they make a lot of trips to the top of Mt. Sunflower.

 

[mgb_phys]

Thats the advantage of a turbo diesel. You can build a 20-30hp engine that is perfectly adequate for driving around town but put a 100-120Hp sticker on it so people will buy it.

 

[mgb_phys]

The electric version of the Smart:
Power: 30 kW (41 hp) from 13.2 kWh battery
Range 110 kilometers / 68 miles (193 Wh/mile)
Recharge time (80%): four hours (100%): eight hours
Top speed: 120 km/h 74.6 mph


Although somehow I don't think this is going to catch on in the USA

 

[mheslep]

The electric version of the Smart:
Power: 30 kW (41 hp) from 13.2 kWh battery
Range 110 kilometers / 68 miles (193 Wh/mile)
Recharge time (80%): four hours (100%): eight hours
Top speed: 120 km/h 74.6 mph


Although somehow I don't think this is going to catch on in the USA

Base price of the gasoline version is apparently http://en.wikipedia.org/wiki/Smart_Fortwo#Made_for_US_market". I wonder how much the EV version costs? The 13 kWh battery should cost ~$6k, or about 4cents/mile.

 

[mgb_phys]

Base price of the gasoline version is apparently $12k

UK price is estimated 12,000 GBP (the gas version is around 9000 GBP)

Interestingly (for this thread) the eu catagorise them on khw/100km (or wh/mile for the uk) but also on the amount of CO2 they emit based on the source of the grid power. So this is road tax exempt because charging it emits 60 gCO2/km, the limit is 100 gCO2/km which the smart diesel also manages.

 

[mheslep]

UK price is estimated 12,000 GBP (the gas version is around 9000 GBP)

Interestingly (for this thread) the eu catagorise them on khw/100km (or wh/mile for the uk) but also on the amount of CO2 they emit based on the source of the grid power. So this is road tax exempt because charging it emits 60 gCO2/km, the limit is 100 gCO2/km which the smart diesel also manages.

The source of the grid power? How does one determine that, other than to average all sources (coal, wind, nuclear,...)? Also, I thought part of the reason for allowing only zero emission vehicles into, say London during the day, was to cut on the downtown toxic emissions - SOx, NOx and particulates. The EV zeros those emissions in the city while the diesel never will.

 

[mheslep]

UK price is estimated 12,000 GBP (the gas version is around 9000 GBP)

So a difference of ~$5,000. Sounds about right. $6,000 battery minus some savings for a cheaper electric only drive train. Still, they need to separate the battery from the upfront purchase price somehow - perhaps make it a subscription per mile - otherwise the EV is too expensive.

 

[Andre]

The top 113 fuel efficent models in the UK do better than 50mpg-US combined.

These aren't Smart microcars, they are mostly 90+Hp turbo diesel hatchbacks.

For some strange reason none of these seem to be available in the US/Canada, even though some of them are built by an American company.
Seat and Skoda aren't familar in America - they are basically rebadged VW Polo/Golf


Maker Model Urban Highway Combined (mpg US)

SEAT Ibiza 1.4 TDI 48.0 73.5 61.9
Volkswagen Polo 1.4 TDI 48.0 73.5 61.9
Mini MINI 50.0 67.2 60.3
Citroen C1 1.4HDi 44.4 69.2 57.4
Mini MINI R55 48.0 65.4 57.4
Skoda Fabia 1.4 TDI 44.4 69.2 57.4
Fiat 500 1.3 16v 44.4 65.4 56.0
Ford Fiesta 44.4 67.2 56.0
Ford Fiesta 1.6 TDCi 45.2 65.4 56.0

Anyway to format tables here?

Hmm
Hmm wasn't my car world record holder mileage? 90.2 mpg. But then again that must be the diesel hybrid. Mine (1.6, 110hp TDi) is not better than about 60 mpg.

 

[mheslep]

Anyway to format tables here?

Latex, but it's cumbersome at first.
https://www.physicsforums.com/showpost.php?p=2230803&postcount=405
https://www.physicsforums.com/latex_images/22/2230803-0.png

 

[mheslep]

The top 113 fuel efficent models in the UK do better than 50mpg-US combined.

These aren't Smart microcars, they are mostly 90+Hp turbo diesel hatchbacks.

For some strange reason none of these seem to be available in the US/Canada, even though some of them are built by an American company.
Seat and Skoda aren't familar in America - they are basically rebadged VW Polo/Golf...

As I understand it, the EPA's extremely strict diesel emissions standards keep most of those vehicles out of the US. [speculation]There maybe a bit of a fix here. I suspect Detroit encouraged the EPA to raise diesel standards in order to keep the Euro diesels out, since generally they grown better at making diesel engines. [/speculation]

 

[Integral]

Base price of the gasoline version is apparently http://en.wikipedia.org/wiki/Smart_Fortwo#Made_for_US_market". I wonder how much the EV version costs? The 13 kWh battery should cost ~$6k, or about 4cents/mile.

I was at about mile marker 220 in Oregon heading south doing about 70mph when a Smart car with California plates PASSED me. Since no one lives in the northern 200mi of Cali, this lady was probably looking at another 500mi in that little thing. Wonder if she could maintain 75mph over the Syskiyous?

 

[mgb_phys]

The source of the grid power? How does one determine that, other than to average all sources (coal, wind, nuclear,...)?

I assume an average, don't know if it's all-eu or per-country. It's an interesting statistic though at 60g/km the electric Smart is only about 30% better than the diesel version.

Also, I thought part of the reason for allowing only zero emission vehicles into, say London during the day, was to cut on the downtown toxic emissions - SOx, NOx and particulates. The EV zeros those emissions in the city while the diesel never will.

it's mostly congestion, there are discounts for electric vehicles but given the small number of the it's mostly just green-washing.
Since ultra-low sulphur diesel and some new buses the traffic pollution has improved - it's now less than a city like Vancouver, it helps that photo-chemical smog isn't usually a big problem in the UK!

The big carrot and stick is that gas+diesel is around $8/gal and road tax is linked to the CO2 emmissions, so it's free for a diesel Smart up to around $500/year for a large SUV

 

[OmCheeto]

I was at about mile marker 220 in Oregon heading south doing about 70mph when a Smart car with California plates PASSED me. Since no one lives in the northern 200mi of Cali, this lady was probably looking at another 500mi in that little thing. Wonder if she could maintain 75mph over the Syskiyous?

One of these days, you are going to be passed by one of http://www.commutercars.com/performance.html" :

Funniest moment at the NEDRA was when this car beat a big block in the quarter mile. The announcer said: "That poor guy. He's going to have to go home tonight, and tell his friends, that he got beat, by a fish."

Not quite as pretty as the 5 Tesla's that drove down from Seattle.

But damn, that car(?) appeared to have violated all of the laws of physics.

 

[mheslep]

I assume an average, don't know if it's all-eu or per-country. It's an interesting statistic though at 60g/km the electric Smart is only about 30% better than the diesel version...

If we believe the average statistic. In the future with new nuclear and wind efforts the EV CO2 figure can continue to drop substantially. No so that diesel. And its all imported (or does the UK have some North Sea shares?).

Edit: 60g/km checks out. I have 953g CO2 / kWh generated from coal (EPA), and you have the Smart EV at https://www.physicsforums.com/showpost.php?p=2315313&postcount=112", or 114 grams CO2/km if the grid were 100% coal based.

 

[mgb_phys]

If we believe the average statistic. In the future with new nuclear and wind efforts the EV CO2 figure can continue to drop substantially.

And a beneficial cycle, as the batteries and motor gets more efficient they use less electricity and hopefully nuclear and wind (probably not solar in the UK!) will increase.

No so that diesel. And its all imported (or does the UK have some North Sea shares?).

The UK is roughly self sufficent in oil and gas - for now at least.

60g/km checks out. I have 953g CO2 / kWh generated from coal (EPA), and you have the Smart EV at 8.4km/kWh[/URL], or 114 grams CO2/km if the grid were 100% coal based.

The UK is about 40% Methane, 35% Coal, 20% nuclear and a bit of hydro.

 

[mheslep]

The UK is roughly self sufficent in oil and gas - for now at least.

http://www.eia.doe.gov/emeu/cabs/United_Kingdom/images/image010.gif
Wow, _just_ for now.

Consumption has been nearly constant for two decades? That's amazing.

 

[Moonbear]

I've seen a few Smart cars around here, even, but am not expecting to see them on the roads come winter. If I still lived in NJ, and all my commutes were on relatively flat, well-maintained roads, I'd give something like that a consideration, especially since the ability to squeeze a teeny car into a teeny space for parallel parking would be quite an advantage on city streets. Unfortunately, even my previously beloved little Focus wouldn't handle the roads around here. Not at all an issue in the summer, other than a slightly larger engine means I can get up the hills at about the speed limit instead of 10 mph below it, but in winter, having AWD and a slightly heavier car is the difference between getting home or being stranded halfway up a mountain or in a ditch. I'm getting to the point where I have enough lectures recorded that I could stay home on snow days and offer my students a pre-recorded lecture instead (so they can stay home too), but when the snow starts while I'm already at work, I really do prefer being able to get home again.

If I had a spouse and could share a vehicle on bad weather days, I'd certainly consider these little, more economic cars as a second car for daily commuting, but I really can't justify to myself owning two cars for one person just so I can have a good weather and bad weather car.

 

[mgb_phys]

I once had to drive from Thunder Bay (Canada) in the middle of winter - and the only thing the car hire place had left was PT cruisers.
They also sold Smarts and you got a free set of winter tires! Apparently they aren't bad, they are fairly light and the engine is over the front wheels so you get decent grip.

The electric ones could be better day-day, the problem with Smarts I have driven is that being very light but tall (very high seating position) you have to fight any cross wind at freeway speeds. So if the battery adds a lot of underfloor weight it could be a good thing.

 

[Moonbear]

The problem here is the mountains. I never had any problem driving in MI, no matter what the road conditions were. Anything from ice to 18 inches of snow, I managed to get to the lab with my old Ford Tempo. But the roads were flat. Here, the smaller cars struggle just with the incline alone, on a good day, so when you add snow or ice, they just can't make it to the top. Believe me, I wish they would. I didn't want to give up my Focus, that was one of my favorite cars ever. It got good mileage, had good pep, and had rear seats that dropped down to expand the cargo capacity of the trunk.

Fighting crosswinds is a big problem for light cars in places where icy roads are common. In some of the Canadian provinces, too light of a car is going to wind up stranded in a ditch, simply because it will get blown off the road by the wind. I'd worry about the same problem in the US in some places (not an issue everywhere, so it's very dependent on where you plan to use the car...not too many people plan cross-country vacations in winter anyway). When I drove my coworker's Prius in OH, I could tell that wind was a problem for that car. I don't have problems with wind where I live now, but when I lived in OH, wind across the very flat land in some parts was noticeable when driving. It was a struggle for a Prius to hang on in wind. I think a Smart car might have even more problems with wind. Where I am now, I'd worry more about it becoming a very efficient snow ski! Just to note, vehicles on the other end of the spectrum don't do well here either. One of my friends wrecked his pick-up truck last year because once the road got too icy even for 4WD to help, it was a very heavy weight to slide downhill into a building. An SUV probably would have just rolled over. It's the middle-sized cars with all-wheel drive that seem to be surviving winters the best around here. Nothing too tall, nothing too heavy, nothing too light.

 

[OmCheeto]

I once had to drive from Thunder Bay (Canada) in the middle of winter - and the only thing the car hire place had left was PT cruisers.
They also sold Smarts and you got a free set of winter tires! Apparently they aren't bad, they are fairly light and the engine is over the front wheels so you get decent grip.

The electric ones could be better day-day, the problem with Smarts I have driven is that being very light but tall (very high seating position) you have to fight any cross wind at freeway speeds. So if the battery adds a lot of underfloor weight it could be a good thing.

hmm... I'd have thought I'd have to explain the Smart's only to an American...

They were designed as urban vehicles.

Why the hell are people taking them on the freeway? That's what Corvette's are for.

 

[Mech_Engineer]

They also sold Smarts and you got a free set of winter tires! Apparently they aren't bad, they are fairly light and the engine is over the front wheels so you get decent grip.

A Smart ForTwo is a rear engine rear wheel drive layout, sounds like the "salesman" fed you a line. Having a good amount of experience in snowy poor driving conditions, I would NOT want to drive a Smart in a snowstorm, snow tires or not.

Front-wheel drive cars do pretty well in snowy conditions however, especially with traction control and snow tires.

 

[OmCheeto]

A Smart ForTwo is a rear engine rear wheel drive layout, sounds like the "salesman" fed you a line. Having a good amount of experience in snowy poor driving conditions, I would NOT want to drive a Smart in a snowstorm, snow tires or not.

Front-wheel drive cars do pretty well in snowy conditions however, especially with traction control and snow tires.

Perhaps you should consider a rear wheel drive Tango. With http://www.commutercars.com/specs.html" of the weight in back, they make pretty good little snow plows.

https://www.youtube.com/watch?v=<object width="560" height="340"><param name="movie" value="http://www.youtube.com/v/uhGCLnAPG88&hl=en&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/uhGCLnAPG88&hl=en&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="560" height="340"></embed></object>

Quite the steal at only http://www.commutercars.com/TangoOrderForm.pdf" .

 

[mgb_phys]

A Smart ForTwo is a rear engine rear wheel drive layout, sounds like the "salesman" fed you a line. Having a good amount of experience in snowy poor driving conditions, I would NOT want to drive a Smart in a snowstorm, snow tires or not.

It wasn't much fun driving 400km in snow in a PT cruiser either!

Front-wheel drive cars do pretty well in snowy conditions however, especially with traction control and snow tires.

My VW Golf always struggled with snow+hill but it was so old that it probably only had half the rated power.
My new Subaru though is amazing I live at the top of a very steep hill in Canada. When it snows only me and a neighbour's Jeep Wrangler get home everytime.
I don't know how you make all the wheels on a fancy SUV spin but the people here seem to manage it.

 

[mheslep]

BYD (China) is going ahead with an electric sedan roll out in the US next year, though not mass market. Like the Volt, BYD's car is also too expensive. Sounds like it will also have a ~100 mile range.
http://online.wsj.com/article/SB125085247014949083.html?mod=wsjcrmain

XIAN, China -- BYD Co., the Chinese auto maker part-owned by Warren Buffett's company, is finalizing plans for an all-electric battery car that would be sold in the U.S. next year, ahead of the original schedule, Chairman Wang Chuanfu said.
...
Mr. Wang said the company plans to pick a specific region within the U.S. and initially market "a few hundred" e6s, priced at slightly more than $40,000, through a small number of dealers. "In the beginning, our target customers are going to be government agencies, utilities and maybe some celebrities," Mr. Wang said. He added that BYD hopes to enter Europe with a similar strategy in 2011 or later.
...
One source of Mr. Wang's confidence in attacking the U.S. car market is BYD's ties with MidAmerican Energy Holding Co., the unit of Mr. Buffett's Berkshire Hathaway Inc. that paid about $230 million for a 9.9% stake in BYD.

The BYD e6 is a five-seat electric-powered passenger car. The company says it takes about seven to nine hours to fully charge when plugged into a regular home outlet. BYD already sells a plug-in hybrid car with a small gasoline engine to charge batteries that is called the F3DM
...