From the Poor Man's Tesla to the Rich Man's Sedan
July 22, 2009 2:54 PM   Subscribe

From the successful conversion of a Porsche 914 into a battery electric vehicle (BEV), MIT's Electric Vehicle Team are now working on the conversion of a Mercury Milan Hybrid into a quick-charging BEV. Instead of the typical 10 to 12 hours for a full charge, the MIT team is looking at an 11 minute charge-time for their BEV, dubbed "elEVen," and they're blogging in detail about their progress. (via)

The Porsche conversion cost $60,000 plus labor for a two-seater that goes from zero to 100 km/h (~62 mph) in 23 seconds, whereas the BEV Milan conversion has a goal of < 9 seconds from zero to 60 mph and a price tag of $200,000 (but much of the materials were donated and the Electric Vehicle Team isn't paid). The batteries alone take under half of the total cost, at about $80,000, but this cost should go down as the market for lithium iron magnesium-phosphate batteries increases.

The amazing charge time requires 350 kilowatts, available through a direct connection to MIT's power plant. Though this kind of power isn't available on a residential level, the dilema of rapid charging stations and vehicles was seen as "a chicken or the egg scenario," with the MIT team showing the feasibility from the vehicle side.
posted by filthy light thief (39 comments total) 5 users marked this as a favorite
 
As for the motor: The car's motor is an oil-cooled, three-phase AC induction motor from SatCon that weighs 138 kilograms including its controller. It was originally designed to be used in a 15,000 kg electric bus. So when it's installed in the 2,000 kg car, it should allow it to go from zero to 60 in under nine seconds and achieve a top speed of 100 mph at 12,000 RPMs (source). Not sure why the article used metric and United States customary system units, but they did.
posted by filthy light thief at 2:57 PM on July 22, 2009


well, then, I'll be the first to say it:

bluh?
posted by shmegegge at 3:05 PM on July 22, 2009


this cost should go down as the market for lithium iron magnesium-phosphate batteries increases.

This sounds like wishful thinking, even though I hope it's true. I can't wait for electric vehicles like these to be commonplace, and battery technology seems to be the biggest roadblock.
posted by knave at 3:12 PM on July 22, 2009




I'm surprised at the weight difference between the Tesla and the Porsche. The Porsche is twice as heavy, which surely contributes to its awful acceleration. But they are both using the same kind of batteries (not lead acid) and the Tesla actually has more.
posted by smackfu at 3:20 PM on July 22, 2009


I bought my Miata in 2000 with the expectation of plopping batteries in it about now, but earlier this year the engine blowed up and I had to have a new one put in. Mebbe next decade . . .
posted by @troy at 3:42 PM on July 22, 2009


smackfu: according to wikipedia, The Porsche 914 curb weight was 940 kg (2072 lb)−995 kg (2194 lb), so those after-market modifications added 1.5+ times the weight, which sounds odd.
posted by filthy light thief at 3:43 PM on July 22, 2009


Electrical vehicles clearly

a) reduce local air pollution
b) reduce dependence on fossil fuels being delivered to customers

but have yet to show

c) that their cradle-to-grave life is not more resource and energy expensive than an internal combustion engine and

d) even if technically feasible that the will exists to replace the onon-renewable with renewable resources on any meaningful scale.

This being said: cool post.
posted by lalochezia at 3:50 PM on July 22, 2009


Funny -- a friend of mine just sent me this a few days ago: ECO Watercraft (first electric jetski). Too pricey, but still pretty cool.

He lives in a high-end neighborhood around a lake where the local HOA has outlawed non-electric boats (noise, etc.). Took me for a ride on his electric-converted pontoon boat and although it was none too fast, it was pretty chill just silently slinking along. The conversion looked like a piece of cake -- just a couple big lead acid batteries and a motor. Couldn't be too expensive -- a quick Google suggests <$500 if you're willing to DIY. Anyhow, I sold him a couple old jetskis he plans to convert to electric. Curious to see the results!
posted by LordSludge at 4:05 PM on July 22, 2009


c) that their cradle-to-grave life is not more resource and energy expensive than an internal combustion engine

While I hope that all of these pollution problems can be resolved quickly and with little fuss, for myself I'm really concerned about the whole atmostpheric CO2 tipping point which we may or may not have reached, and might find it some other waste streams acceptable if it can keep us from being Sauna Planet in 2030.
posted by hippybear at 4:19 PM on July 22, 2009


Where did it come from? I didn't mean to put it there!
posted by hippybear at 4:20 PM on July 22, 2009


World Famous: I think lalochezia is talking about the will to replace fossil-fuel-driven power generation with renewable sources, like wind/solar/etc. Otherwise, an electric car is just a coal-fueled car with an exceptionally long tailpipe.
posted by Kadin2048 at 4:21 PM on July 22, 2009 [1 favorite]


Lalochezia, my understanding is that the cradle-to-grave carbon footprint (if not energy footprint) is less - even if only marginally so, but the real killer to the advantage is the efficiency loss of the electricity network as it currently functions (somewhere between 30 %- 60% of power generated at a plant is lost I understand, due to a combination of peak demands and copper wire resistance).

So in terms of carbon footprint, countries like France that have a lot of nuclear, EVs make _a hell_ of a lot of sense. In very heavily coal dependent countries, those gains are reduced somewhat.

This said, most countries now have 100% green power available for purchase, and if you're prepared to pay a $10 000 or more premium to get an EV, my guess is you'd be okay with paying for some green power.

I'd do it in a shot right now but for the fact we just bought an apartment, and worse yet: there's no outlet in our new garage!
posted by smoke at 4:44 PM on July 22, 2009


Otherwise, an electric car is just a coal-fueled car with an exceptionally long tailpipe.

Following on from what I just said, this isn't exactly correct. You're right in that it's just a coal fuelled car, however from an efficiency perspective, you're gonna get a lot further per, well, any unit you care to name - carbon tonne, kilowatt, etc. - than would with fuel burning. Fuel burning is really tremendously innefficient.
posted by smoke at 4:47 PM on July 22, 2009 [1 favorite]


My perception is that there is no will whatsoever to do this, nor will there be unless it is cost-based.

Agreed. Implemented properly, a carbon tax might create the cost incentive by penalizing pollution, but I'm of the opinion that the odds of creating a carbon tax structure that's not terminally warped by its passage through the sphincter of Washington politics are roughly on par with discovering cold fusion.

The real question is whether the ultimate cost driver — petroleum depletion — will happen before we've done irreversible damage to the biosphere, because I see no evidence that we'll do anything to curb consumption (aside from crashing our economy; that did seem to do the trick for a while) before it's gone.

Also, I think hippybear brings up a good point regarding diversity in waste streams. It might be worth investigating power generation that isn't necessarily 100% clean, if it produces different waste products. That's always been my feeling about nuclear power: it may not be clean, but it's dirty in a different way, and for that reason alone deserves serious consideration. A small amount of various types of waste products might be significantly better overall than a lot of one particular waste product.

Similarly, CO2 capture systems — which I once heard someone describe as "trading landfill pollution for atmospheric pollution" — seem like they could be a good idea as well, but of course they're cost centers that would only exist inside some regulatory framework that made them desirable to use.
posted by Kadin2048 at 4:50 PM on July 22, 2009 [2 favorites]


so those after-market modifications added 1.5+ times the weight, which sounds odd.

Aha! It seems like the IEEE confused pounds and kilograms. This page at MIT says the modifications led to a net gain of 400 lbs, bringing it to 2500 lbs, and the chart in the article says it weighs 2500 kgs.
posted by smackfu at 4:56 PM on July 22, 2009


Otherwise, an electric car is just a coal-fueled car with an exceptionally long tailpipe.

This red-herring thinking just isn't relevant when the total emissions of that coal fuel are as little as 1/100th of what a regular gasoline car outputs to go the same distance.

Almost every step of the way, the greater efficiencies of electricity, regenerative braking, central power generation, mass generation, static facilities, dedicated facilities, and so on, can all adds up to a staggering difference.

Additionally, coal fuel is an American thing - there are a lot of countries where coal accounts for about as much of the grid as renewables do in the USA. Electric cars are a global solution to a global problem. The American grid is unfortunate, but not definitive.
posted by -harlequin- at 5:01 PM on July 22, 2009 [1 favorite]


Additionally, it's far easier and far cheaper and far more effective to impose far far better emissions scrubbing on powerplants, than on cars. You will never see cars installed with biofuel-algae farms that feed off the C02 from the tailpipe, the C02 is going to go straight into the atmosphere. But at industrial settings, in stationary facilities, that sort of waste-into-wealth approach is standard operating procedure.
posted by -harlequin- at 5:12 PM on July 22, 2009


The amazing charge time requires 350 kilowatts, available through a direct connection to MIT's power plant.

I realize you recognize that this "isn't currently available" but I think you do a great disservice to just how ludicrously unavailable these road-side power plants actually are.

And just how is MIT's power plant generating electricity? Ah. Gas.
posted by Civil_Disobedient at 5:19 PM on July 22, 2009


I realize you recognize that this "isn't currently available" but I think you do a great disservice to just how ludicrously unavailable these road-side power plants actually are.

How is it ludicrous?
There are electric substations throughout the cities of the world already, so the early foundations are laid. As with H2 cars and other exotic fuels, you start with one refueling station in the city where the first trial-cars are sold, and add more as they penetrate the market further (or don't, if they don't).

But these are not exotic fuel cars - they could be plugged in at any old home overnight, so they can lead into the market ahead of the charging stations. There is not a chicken-and-egg problem.

It might make sense to set up charging stations near substations rather than to try to pipe that power to existing gas stations and tack on the service there - gas stations are owned and operated by oil companies, not electric utilities. And with a 15 minute refueling wait, the liquid gas-station layout doesn't really work anyway (you'd want a fast food joint or cafe onsite or nearby for example), and with that kind of voltage, it ain't going to be self-service :)
posted by -harlequin- at 5:53 PM on July 22, 2009


So much effort expended in solving the wrong problems. We don't need high acceleration or (necessarily) fast recharging. We need reasonable capacity. If I can't drive all the way to work, I can't buy the car.
posted by DU at 5:57 PM on July 22, 2009


With the advent of cheap(er) solar tech, why are none of these electric or hybrids turning the roof into a passive collector of juice? If you drive an EV to work and park it in a big-ass lot all day while you're working, especially someplace like CA, I would think a reasonable amount of battery charging could take place while you're inside. (Even if it's just a percentage, it's better than nothing, at no real cost compared to the overall cost of the car.)

The rapid charge in this project isn't that interesting. "We can charge these batteries in seven seconds by exploding a nuclear device inside the car!" is what it amounts to. That said, I like to see any EV project. A friend is turning an old junker Morris Mini into an electric car for around city putting.
posted by maxwelton at 5:59 PM on July 22, 2009


why are none of these electric or hybrids turning the roof into a passive collector of juice?

My guess is because the car companies are convinced that people will not trade looks for efficiency. The original Honda Insight and the GM EV1 both had skirted rear wheels, but none of the new cars have them, even though they improve efficiency.
posted by smackfu at 6:25 PM on July 22, 2009


why are none of these electric or hybrids turning the roof into a passive collector of juice?

I just saw today a television commercial for the Prius 3GS or whatever they're calling it. They've put solar panels on the roof to power ancillary things like ventilation and such.

So, it's happening.
posted by hippybear at 7:31 PM on July 22, 2009


I look forward to the day when ... electric vehicles can not only be decent transportation, but can also handle well and be decent sports cars.

The best way to achieve that is in reverse - foster a professional sports interest in electric racing, then allow the deep-pocketed engineering super-skills that develop trickle down to the consumer market. That's how Honda got so good at building tough, tight engines.
posted by CynicalKnight at 7:44 PM on July 22, 2009


why are none of these electric or hybrids turning the roof into a passive collector of juice?

Not enough juice there to be worth it. Say a roof panel gets you 2 square meters of collection area. The solar constant is 1 kW/m2. Assume you live in the Urumqi Desert and so all of that actually reaches the car. Divide by 2 for occlusion by the Earth and by another π/2 since you don't have a sun angle tracker. That gets you an average of 0.67 kW, assuming your panels have 100% efficiency, which photovoltaics can't (quantum efficiency problem). Assume you have some crazy exotic high-efficieny cell and only divide by another factor of 4. Your average power output is about 160 watts. That's less than 1/2000 of the MIT fast-charge power output— it'd take over two weeks to charge your car, assuming no other losses.

(Executive summary: We're accustomed to very energy-hungry technologies; a solar array that's useful to run your car is too big to bolt to the top of your car.)
posted by hattifattener at 8:14 PM on July 22, 2009 [2 favorites]


DU: "So much effort expended in solving the wrong problems. We don't need high acceleration or (necessarily) fast recharging. We need reasonable capacity. If I can't drive all the way to work, I can't buy the car."

The thing is that fast recharging is a pre-requisite for practically allowing capacity to go up (although battery weight and safety are the main constraints, AFAICT). A bigger battery takes longer to charge, and fast recharging also has the side-benefit of making it possible to get more range on trips by stopping briefly at a charging station.

Capacity, or energy density, isn't so much of an ignored issue, it's just that it's not an issue isolated to cars. Laptops, cell phones, and MP3 players also demand smaller and higher capacity batteries, and the technologies can generally scale to very large batteries.

Unrelated: A lot of people seem to think MIT's 11 minute charger using a dedicated power plant is cheating, but I think it's still a useful technology, as home users could get a charger with its own battery or supercapacitor that charges from an appliance circuit over several hours. It could also offer trickle charging for when a person hasn't waited long enough, and wants their range improved ASAP. Office parking lots and "charge" stations could get high-wattage powerlines installed and recoup the investment by selling the power. Naturally, power companies will still incentivize slow charging at off-peak hours or via the home capacitors, so charging from a parking lot quickly will likely be expensive.
posted by mccarty.tim at 8:17 PM on July 22, 2009


Just some back of the envelope numbers:

(350 kilowatts) * 11 minutes = 231 MJ
at 240V that implies 1.9 Mcoulombs charge
or, ideally, about 8 Farads at 240V, if I did my math right.

I would like to see that kind of capacitor technology become commonplace, just because you could make one hell of a railgun with it.
posted by Kadin2048 at 11:41 PM on July 22, 2009


A bus engine? Good heavens, won't stomping on the pedal simply flip the car on its roof, wheels screaming, from the torque? (I thought wicked awesome torque was one of the big selling points of electric motors.)
posted by wenestvedt at 5:54 AM on July 23, 2009


So much effort expended in solving the wrong problems. We don't need high acceleration or (necessarily) fast recharging. We need reasonable capacity. If I can't drive all the way to work, I can't buy the car.

How far away is your work? Most electric cars haven't been pushed for extensive commutes, but local transit. GM's EV1 could go 160 miles with NiHM batteries in 1999. REVAi are limited to 50 miles.
posted by filthy light thief at 7:23 AM on July 23, 2009


smoke: ...you're right in that it's just a coal fuelled car, however from an efficiency perspective, you're gonna get a lot further per, well, any unit you care to name - carbon tonne, kilowatt, etc. - than would with fuel burning. Fuel burning is really tremendously innefficient.
-harlequin-: ...the total emissions of that coal fuel are as little as 1/100th of what a regular gasoline car outputs to go the same distance.
I think this idea may be optimistic.

I was disappointed to learn that most existing power plants (coal, gas, and nuke) typically convert 40% or less of the heat they generate into electrical power. The electric grid itself wastes 5% or so of that. Then the battery charging process itself wastes some of what's left.

All in all, the coal-to-battery process is probably, at best, only about 33% efficient, which is in the neighborhood of a modern internal combustion engine, and less than the claims (40%+) made for some advanced diesels and hybrid motors.

The flexibility of using electric power to fuel cars may be a boon, because other sources of electricity (like wind and solar) can be used. But I don't think there's any reason to believe electric power will, in and of itself, offer huge efficiency gains.

Here in the US, I wouldn't be surprised if consumers buy gigantic electric SUVs (assuming they become available), which could in the end use more fuel and produce more emissions than a small gasoline-powered car would. There are some precedents for that sort of behavior.
posted by Western Infidels at 8:51 AM on July 23, 2009


Sorry, I meant "power-plant-fuel-to-EV-battery" process, not "coal-to-battery" process.
posted by Western Infidels at 8:53 AM on July 23, 2009


Western Infidels: You've listed all the energy losses, but missed most of the areas where electricity does, in and of itself, offer huge gains. Furthermore, you're vastly overstating the efficiency of internal combustion engine cars (33% is not in the neighborhood, it's in the neighborhood of their thermodynamic limit - not what a car actually gets in the real world. Add 100% energy losses to that (idling at lights, gridlock), continually dumping most of your fuel out through the brakes instead of putting it back into the fuel tank to be reused, etc etc. and for real-world use rather than the hypothetical infinite freeway, the picture starts to change)
So from my position of over optimism, I think you're being overly pessimistic ;-)

(That said, I'm also in the camp that doesn't particularly care - electricity can be made anywhere, anyhow you please, forever. Gasoline is the opposite. Any and all issues are settled right there - and even though we can't see that now, each successive year will make that reality clearer and clearer until the sheer inescapably is... inescapable :)
posted by -harlequin- at 11:32 AM on July 23, 2009


That said, I'm also in the camp that doesn't particularly care - electricity can be made anywhere, anyhow you please, forever. Gasoline is the opposite. Any and all issues are settled right there - and even though we can't see that now, each successive year will make that reality clearer and clearer until the sheer inescapably is... inescapable

I just hope the manifestation of that inescapable reality isn't one where we no longer have a sustainable food chain for ourselves because the climate has tipped and nothing can grow like we want it to.

That is the possible reality which wakes me up at night in a cold sweat. Every day we don't make progress away from burning shit for power is a day closer to it.
posted by hippybear at 2:22 PM on July 23, 2009


Furthermore, you're vastly overstating the efficiency of internal combustion engine cars

Unfortunately the engine efficiency isn't what makes the internal combustion engine the dominant motor type for human transport. You have to store the energy and you have to be able to move it around easily (and cheaply).

There are electric substations throughout the cities of the world already, so the early foundations are laid.

There are vastly more gas stations in the world. In any urban/sub-urban environment (the ones where there are the most cars) you're looking at several orders of magnitude. That's your demand. Now, you really, rationally expect that many people to queue up for their allotted 130 miles of driving charge? So, just build more stations, right? Except electrical substations are way, way more expensive to build than simply digging a hole in the ground and throwing a big tank in it. Again, probably a couple orders of magnitude.

If they developed some super-capacitor that could hold 1000 miles worth of charge, then people might be willing to take an hour on a Sunday to drive down to the nearest ChargeSpot™ and wait in line to "fill" up their car. Barring that, our society will be using oil until the taps run dry.
posted by Civil_Disobedient at 3:53 PM on July 23, 2009


I believe we are at the beginning of a transformational period, not unlike the time following the advent of the internal combustion engine. Our lives are going to be different going forward, one way or another. Either we will address global warming, and our world will be a lot greener pretty quickly. Or we won't in which case the transformational change will ultimately lead to mass die-offs and an ever-decreasing level of biodiversity on our plant.

Oil consumption is a self-correcting problem, if we remain dependent on it. As the environment grows more hostile to human (and other) life and we die off, we will naturally use less oil, and eventually the climate should correct, assuming enough of us die off. If enough of us don't die off and we start coming recovering in population and resource usage, then the problem will reappear and cause another die off, and so on. Of course, if we're not careful, we could put the atmosphere into a self-perpetuating death spiral and turn Earth into a Venus clone, with 700 degree temps and sulfuric acid rain and whatnot, and there would likely be no coming back from that.

So, I hope we tackle the problem head-on. The longer we wait, the worse it is going to be, the more money it will cost, and the higher the chance of that self-perpetuating Venusian death spiral becoming our future. And that would royally suck.
posted by jamstigator at 4:45 PM on July 23, 2009


Civil Disobedient:

There are vastly more gas stations in the world. In any urban/sub-urban environment (the ones where there are the most cars) you're looking at several orders of magnitude. That's your demand.


My googling suggests the opposite - either about the same substations per capita as gas stations, or up to two orders of magnitude more substations than gas stations, depending on what you include and where you look.

But as I said, fast-charging stations are not necessary - they are a convenience that will appear as the market matures. Electric cars like the volt look likely to be practical right out of the box, no charging stations needed, because they can just tap some of the gas infrastructure in the statistically uncommon event that a day's use exceeds the expected battery capacity. That's a nice, easy, practical way to transition fuels and give new infrastructure time to develop, rather than needing it and stalling because of it.
posted by -harlequin- at 4:54 PM on July 23, 2009


I feel like I should comment here because I'd like to mention that for an electric scooter, right now, it takes 10 hours to charge enough power over domestic power lines to go 70 kilometers. At least that's what my bike is rated for, and the battery for my little 170 pound vehicle is 50 pounds, a weight that I need to lug up and down 8 stories every single fucking day. Really, somebody needs to do something about charge time, or my spine is going to snap one of these days.
posted by saysthis at 2:45 AM on July 24, 2009


saysthis: Fifty pounds sounds like it might be a lead-acid or NiMH battery. If that's the case, and you wanted to DIY a bit, maybe you could rig up something with Lithium Ion or better yet LiPO batteries. LiPOs have just about the highest power/weight ratio of any battery technology currently on the market, at least that I'm aware of.

They've completely revolutionized the R/C aircraft world, and I have seen people combine cells to create some very high voltage and current batteries.

Of course, if your scooter is already using 50 pounds of Li+ or LiPO...I think that's just about the cutting edge. (Although you can cut charge time by cooling the cells; apparently it's the heat dissipation that's the limiting factor during recharging for most chemistries. I'm actually very curious how they're handling the heat issue in the MIT '11 minute' car.)
posted by Kadin2048 at 9:16 PM on July 24, 2009


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