Green GT's All-Electric Supercar Unveiled

Mike writes "Swiss auto company Green GT recently released the first details on a svelte all-electric supercar that is being heralded as the most powerful electric race car ever built. Designed with the 2011 Le Mans race in mind, the Twenty-4 will boast a sleek carbon fiber chassis and twin 100-kw electric motors totaling 400 hp — enough to push the vehicle from 0-60 mph in 4 seconds flat, and to a top speed of 171 mph. GreenGT's head engineer Christophe Schwartz has stated that 'The GreenGT Twenty-4 design study could become our 2011 Le Mans Prototype electric racer, or it could even become an electric road-going supercar. There is a possibility to do both!'"

Comments

24 hour charge??

[gbulmash]

What interests me is how they'll power the car in a 24-hour race. There don't seem to be details on that.

According to their site, there's a large solar-powered charging station (100 square meters of photovoltaic surface) which can be used to charge the car between races, but unless they're seriously loading the thing with batteries, they're either going to need long pit stops for charging or the ability to swap out battery packs as fast as other cars can pit for fuel.

On the other hand, with their target date two years out and the rapidly evolving electric car scene, I wouldn't be surprised if there was some hot new prototype hitting the car show circuit around then that blew their doors off.

Re:24 hour charge??

[oldspewey]

My vote goes to the swappable battery packs

Re:24 hour charge??

[alta]

Done right, I can see a mechanical battery change process... Much faster than gasoline fuel.

1. Pull up to red line.
2. 4 clamps grab wheels
3. car is left up in the air 2 ft, while spent batteries fall out, exit passenger side on conveyor belt.
4. new batteries come in at same time, put in proper position.
5. Car drops, latching in new batteries
6. clamps release wheels.
7. 0-60 in 4 seconds.

I could see a see a 4 second pit stop here.

Skip the 'lifting' process, and have them drop into a recess and you get rid of the GForce limitations on the driver. But you also make it so the system is embedded in the ground or the driver goes up/down a ramp.

Then again, remember how they want to shoot microwave power from space? Imagine if your power is beamed to you from the center of the track. (sounds dangerous)
And then instead of restrictor plates, you get resistor plates.

Re:24 hour charge??

[Yvan256]

How about Supercapacitors?

Re:24 hour charge??

[fiannaFailMan]

It's been a while since I watched that race, but from memory I think Le Mans pit stops aren't the 4-second in-n-out with four fresh tyres and a full tank that you get in Formula 1. They last a bit longer than that.

Re:24 hour charge??

[Rei]

How much is "a bit longer"? Several pre-production cars have already demonstrated 10 minute charging, while BYD claims it on the production F3DM. If you have a really crazy cooling system and, say, a 250kW Aerovironment PosiCharge charger or 300kW Norvik MinitCharge charger, you should be able to do ~5 minutes per ~120 miles.

Re:24 hour charge??

[dk90406]

20-30 seconds for tire change. About a minute if the car needs refueling as well. They are not allowed to change the tires while fuel is being pumped.

Re:24 hour charge??

[Geoffrey.landis]

How much is "a bit longer"? Several pre-production cars have already demonstrated 10 minute charging, while BYD claims it on the production F3DM. If you have a really crazy cooling system and, say, a 250kW Aerovironment PosiCharge charger or 300kW Norvik MinitCharge charger, you should be able to do ~5 minutes per ~120 miles.

This car has two hundred-kilowatt motors in it. If you use a 250 kW charger to charge batteries that you're then discharging at 200 kW, you need to spend 45% of the time charging.

Take a look at the air intakes on that car. It doesn't need air to burn, so those intakes have to be entirely for cooling airflow. Yow.

Re:24 hour charge??

[Anonymous Coward]

How cool would it be if they put a slot with 2 metal strips either size of it all around the race track, and powered the car via that?

Re:24 hour charge??

[C0vardeAn0nim0]

lemans pit stops usually involves replacing tires, break system (disks, pads, etc.), sometimes even the pilot is replaced. no need to rush when you have 20-16 hours to catch up with the other cars.

Re:24 hour charge??

[bennomatic]

There's a lot of braking in those on-street races. I wonder if they're putting in technologies from hybrids like regenerative braking, possibly some sort of system to capture some of the energy lost on tight turns, etc... and recharging the battery for fewer stops.

If an electric wins the Le Mans, or even has a pretty good showing, the whole industry will start to re-gear overnight. When Joe Six-Pack says, "Gas-only sucks! I want the kind of hybrid technology that'll make me feel like a winner!!", it'll represent a sea change.

Of course, if it comes in dead last, that could be just as big a PR problem.

Re:24 hour charge??

[Rei]

Even racing supercars don't come close to running at 100% throttle nonstop -- and when they do slow down for turns, regen puts power back into the pack. Li-ion regen in the Roadster, for example, is around 65-70% efficient if I recall the numbers correctly. So you only lose 30-35% of the energy expended on an accel/decel cycle; the rest of your losses are primarily aero and rolling. Aero, which should be the primary loss mechanism, will depend heavily on how much downforce there is.

I agree, though, in that it's probably not practical for the race unless the pit stops are long.

Re:24 hour charge??

[need4mospd]

Let's see, grabbing the car by the wheels to lift it? Batteries falling out of the car from 2ft? Dropping a car down 2ft onto the fresh set of batteries? Then you go on about microwave beams shooting around the track?

You're looking to make this race exciting aren't you?

Re:24 hour charge??

[Sandbags]

well, it doesn't have to run for 24 hours on one charge, the other race cars are lucky to run 70 minutes on a tank of gas...

If it can make 150 miles, when they pull in to swap the tires, and jack it up, they could also drip the batteries from the under carrige and replace them en masse.

high performance charging system run on generators pit-site could bring those Li-Ti or Li-Su batteries to full charge in 30 minutes...

My concern is the 400HP total... most of it;s competition does 0-100 in about 8 seconds, and runs in the 600-1000HP range... For instance, the Audi Deisel (first time ever) ran at 650HP http://www.auto-power-girl.com/specifications/audi/audi_r10_le_mans_race_car-540

Heck, the "lemans edition" steet cars sold as production vehicles very often peak over 500HP... and those are not the race models, but simply collector cars.

Re:24 hour charge??

[Bakkster]

And, if they can get more time between stops than on the gas engines (quite possible with regenerative braking) or some form of weight advantage (not sure about weight rules at Le Mans), this car could scream.

Re:24 hour charge??

[billybob_jcv]

I disagree on the air intakes - generating downforce and brake cooling are also the reasons the air intakes are there. I'm sure those motors do produce heat - but I will bet it's still much less than an equivalent combustion engine.

Re:24 hour charge??

[caffeineboy]

This is how it was done in SAE formula lightning.

There is a video of the WVU team doing a pit practice here. These are college kids, probably engineers and not mechanics. A real pit crew could do it in much less time.

Re:24 hour charge??

[oldspewey]

Yeah, they aren't going to win too many races with a pit time of 1 minute +

Re:24 hour charge??

[jollespm]

In LeMans, every second counts. Check out the movie "Truth In 24" to see what goes into winning. It is (was?) a free download on iTunes.

Re:24 hour charge??

[PopeRatzo]

You know, thinking about an electric car possibly winning Le Mans makes me realize just how quickly the general public's mentality regarding the importance of petroleum-based fuels for transportation could change.

I've heard many times from gearheads how they'd never be caught dead in one-a them electric-battery toy cars, that gasoline is king, etc. As soon as Kyle Bush takes one for a spin in the brickyard, that's gonna change. Obviously, there won't be an electric car running in a NASCAR race because of the narrow rules, but a couple of pictures of Tony Stewart or Greg Biffle behind the wheel of an electric car would change a lot of minds.

I'm anxious to see what the arrival of very fast electric cars is going to do to auto racing.

Re:24 hour charge??

[Tanktalus]

Well, not against gas-powered cars, but in an all-electric race, perhaps... (if anything gets electric cars kick-started in the public consciousness, it'd be an all-electric indy or something)

Re:24 hour charge??

[Tanktalus]

VERY cool. Especially the crashes.

"Oh, that's gotta hurt - I just hope the driver doesn't get out of the car!"

Re:24 hour charge??

[billybob_jcv]

Or, if it wins, they'll outlaw them from racing at Le Mans... http://www.mazdausa.com/MusaWeb/displayPage.action?pageParameter=mazdaSpeedMotorsportsRacingHeritageCommon&sectionParameter=heritage05

Re:24 hour charge??

[Anonymous Coward]

Even if the quick battery swap is doable, and it certainly sounds reasonable, more importantly can the current batteries last as long as a tank of gas so it doesn't have to pit stop more often than the rest of the racers?

Re:24 hour charge??

[b0bby]

Take a look at the air intakes on that car. It doesn't need air to burn, so those intakes have to be entirely for cooling airflow.

FTA: "The car was designed by five students from the CCi du Valenciennois school." In other words, it's just as likely that the air intakes are there to look cool... Also, my French isn't the best, but from the green-gt site it looks like they are planning to build a prototype this spring, then maybe add hydrogen as a fuel source fall 2009, then make 20 or 25 cars by the end of the year. I'll believe it when I see it.

Re:24 hour charge??

[dontgetshocked]

I would imagine that thru pit stops they will change the battery or something!

Re:24 hour charge??

[Anonymous Coward]

You're looking to make this race exciting aren't you?

Face it, the only time most of these races are exciting is when someone decides they want to turn right.

Re:24 hour charge??

[ckthorp]

Audi took almost a 1 hour stop for maintenance and still took 3rd.

Re:24 hour charge??

[k-vuohi]

Saying "We'll do an all-electric race because, let's face it, they're not that good against the fossile fuel powered ones" may raise public consciousness, but not a desire buy one. Still, 400hp from an electric car is getting there.

Re:24 hour charge??

[Repossessed]

I assume they'll use the new rapid charging battery tech. Pump the solar panels into some very big capacitors, then unload them into the batteries.

http://web.mit.edu/newsoffice/2009/battery-material-0311.html

Re:24 hour charge??

[thrull1]

While they talk about recharging the car between races, there is a diagram on their website http://www.green-gt.com/index.htm that illustrates that they will be using Hydrogen to store the energy and using fuel cells to generate electricity.

Re:24 hour charge??

[LandDolphin]

They should really make a race where you can enter any stock car. But what would you call such a race?

Re:24 hour charge??

[Anonymous Coward]

Holy crap. That is waaaay too complicated.

1. Pull up to red line.
2. Pit crew opens quick - release hatch.
3. Press release lever.
4. Slide out battery pack, possibly onto a small wheeled cart.
5. Slide in new battery pack, possibly using a small wheeled cart.
6. Close hatch.

No need for elaborate lifting mechanisms. No reason to rebuild the pit, install ramps, or do other acrobatics. And while one or two people change the battery, the rest of the crew is doing the usual stuff like changing the tires which is going to be the longest part of the procedure in any event. And if you just need some more fuel, this could still be performed in a matter of 4 to 6 seconds.

Notice that I use the term "Battery" in the singular while you use the plural form. There is no reason to assume that you would need to use more than one battery.

Re:24 hour charge??

[Gordonjcp]

I've heard many times from gearheads how they'd never be caught dead in one-a them electric-battery toy cars, that gasoline is king, etc.

I'd be quite happy to drive an electric car, *if* it had exactly the same operational parameters as my petrol car. That is, 400-500 miles per "tank", recharge in under five minutes, payload of around 800kg for a maximum all-up weight of about 2200kg + 1300kg trailer, 0 to 60mph in less than 15 seconds and a cruising speed of at least 90mph.

Forget 0 to 60 in four seconds, I'm never going to use that. Give me some range.

Re:24 hour charge??

[budgenator]

Electrics can and do kick serious but in drag racing, barely streetable Corvettes and Vipers getting hole-shotted of the line and their doors blown off in the traps by something that looks like what your Grandmother might drive to the grocery store make an impression too! Check out White Zombie or 0 to 60 in under a second

Re:24 hour charge??

[vikstar]

I saw a f1 team roll a new nose cone on a trolley. It would probably be much easier to develop a trolley to swap out the batteries in one motion. First trolley grabs the batteries and moves them out of the way, second trolley with the new batteries rolls up to the side and slides them in. Sure it probably can't be done right now this very minute, there would be problems to overcome, but c'mon, a battery trolley with rails is beyond human capacity? (no pun intended).

Re:24 hour charge??

[John Hasler]

If you are making three times as many pit stops as the other cars you'd better be three times as fast as they are. Should only take a few seconds to change batteries, though.

Re:24 hour charge??

[John Hasler]

> As soon as Kyle Bush takes one for a spin in the brickyard, that's gonna change.
> Obviously, there won't be an electric car running in a NASCAR race because of the
> narrow rules...

"IndyCar" rules are at least as restricitve as NASCAR rules. "IndyCars" all have identical powertrains and *governors*.

Re:24 hour charge??

[John Hasler]

Unlike the gas buggies, the electric will deliver most that 400hp to the wheels.

Re:24 hour charge??

[Geoffrey.landis]

I disagree on the air intakes - generating downforce and brake cooling are also the reasons the air intakes are there. I'm sure those motors do produce heat - but I will bet it's still much less than an equivalent combustion engine.

Well, downforce would be produced much better from aero surfaces. And, with regenerative braking, brake cooling is the same thing as cooling the motors/batteries, but just with the current flowing the opposite direction.

Re:24 hour charge??

[ElectricRook]

An electric car will do pretty well. It can provide a good weight to horse power ratio. One of the challenges in electric cars, is battery life. Discharge a lead acid battery more than 10%, and it's life goes from years to weeks. In a race, you don't care about battery life past the race. And with some engineering, a battery swap could come down to a reasonable pit stop.

But the sex-appeal of something that does not rock the stands, or throw a flame is really low.

Re:24 hour charge??

[ElectricRook]

Um... Stock car race?

There are many classes of racing, many of them very close to stock production with the addition of safety equipment.

However not having a top speed of 250MPH kind of takes the appeal out of it.

I have a friend that races in a mazda miata class.

But it's important to remember that a motor racing hobby is much more expensive and addictive than say Heroin.... (er maybe not quite more addictive)

Re:24 hour charge??

[ElectricRook]

You forgot about the $12k battery pack replacement every 5 years or 60k miles.

Re:24 hour charge??

[Anonymous Coward]

I'm not sure I get your question. What's wrong with having batteries charged up and swapping batteries out? It's not as if the gasoline/petrol and diesel folks are refining their stuff from sweet crude barrels onsite. They most likely are going to have a massive set they just swap out.

Aside from swapping batteries out, there's also liquid battery tech, where the charged and uncharged separates out. They could simply pump out the old and in with the new charged liquid. The problem there though is the movement of the liquid during the race as you turn and hit race curbs and get rear ended and what not that occurs during a race.

The problem isn't how they are going to do it, it's are they going to compete with any methodology they come up with. There were reasons Audi, which themselves or their engines have dominated most recent LeMans, went to diesel--power density over gasoline is one of them. The electric car may win out on engine reliability and easier to swap out parts, but the traditional vehicles will have fewer pit stops for fuel.

The other issue that people seem to ignore is that LeMans isn't exactly a level playing field to begin with. LeMans took action against the Weinkel engine users and manufacturers. That engine is superior in power to weight ratio, which means more fuel can be carried compared to similar horsepower but traditional engines, and in fuel economy because of the weight difference. Additionally, I also believe it was a more efficient engine still even if pulling the same weight.

Anyways, LeMans handicapped anyone using the Weinkel years ago. So even if the electric whoops the high compression diesels, the electrics still will not have gone up against the best.

Re:24 hour charge??

[MichaelSmith]

Build a machine to load the batteries. The new pack gets pushed in from the right. This pushes the old pack out the left where a human helper drags it out of the way so the car can drive off. Maybe when the car parks it gets pushed off the ground by pins in a lift mechanism. That fixes the location of the battery bay and enables automatic tyre changing at the same time.

Re:24 hour charge??

[ZosX]

Ahhh grasshopper. You are confusing horsepower with torque. A diesel engine with 100hp can create hundreds of pounds of torque. Horsepower doesn't tell the whole story and is not representative of how much torque the engine can produce, which varies with engine speed. A typical car has a torque curve that starts out gradually climbing and then reaching its maximum around 3000-4000 rpm (just an example here people) and begins to flatten and decline towards the red line, say at 6000 RPM. That means that this engine is only outputting peak torque at the maximum point in the curve. An electric engine has a purely linear torque scale. At 1 RPM it is generating 500lbs of torque. At 6000 RPM it is generating 500lbs of torque.

"The torque of an electric motor is independent of speed. It is rather a function of flux and armature current." - Wiki

Coupled with a continuously variable transmission (ala Prius) electric engines are both highly efficient and insanely powerful. If we can get past the hurdles of energy storage, which clearly dominates this discussion, then internal combustion engines will start to look as antique as the coal fired steam engine. I mean seriously. Which is more elegant, a giant motor, a shaft of metal surrounded by magnets and a coil of wire which is like 95% efficient or an insanely complex machine made of thousands of moving parts and components, which including a whole lot of small motors is only like 23% efficient at best? Never mind all the crap you had to go through to get the fuel that only yields 23% efficiency. Oh and forget about the terribly messy process of getting some black tar that was supposed to probably stay in the ground for a few million more years to cook down and refine into gasoline. (And people wonder why they haven't been building new refineries in the United States, maybe those people should have one in their backyard) I mean geez, solar panels are starting to exceed those kind of numbers already.... To hell with spending money on how to suck out the last few drops of oil from some sandy shoals. We should be spending all of our money on figuring out how to cleanly produce electricity. Our very future depends upon it in more ways than one.

Hmmmmmm....now where do we have a huge source of energy close by?

Re:24 hour charge??

[ZosX]

Would the cars be guided by a metal pin in a slot as well? I don't see how that could possibly qualify as racing.

Re:24 hour charge??

[spun]

Most Formula 1 and Le Manns cars utilize Bernoulli tunnels under the car to produce significant downforce.

Re:24 hour charge??

[spun]

Le Manns is not NASCAR. Right turns are encouraged.

Re:24 hour charge??

[MeatBag PussRocket]

LeMans is not NASCAR buddy. there are plenty of "right turns" chicanes, hairpins etc.

also FYI the current F1 rules employ hybrid technology, they allow electric supplemental power (i believe up to 80hp) and regenerative braking. AFAIK most serious teams are using it.

Re:24 hour charge??

[Hashi Lebwohl]

A really, really long extension cord.......

Re:24 hour charge??

[Anonymous Coward]

Autocross

Re:24 hour charge??

[fractoid]

Serious answer - I've had a long-time scheme to build an electric go-kart track using basically this idea (stationary power supply, with pickups to get the power to the karts). I was more imagining a high ceiling with a bumper-car style electrified mesh on it, though. For full sized track racing it doesn't make much sense but for an indoor kart track it's a perfect fit. You can dial your karts' speed settings individually for the drivers (hence don't need to have more than 2 different ranks of kart, rather than the 3-4 that most places have), you don't need to worry about ventilation so much, no ongoing fuel costs, no expensive engine maintenance, easy remote activation of 'limp home' mode for yellow flags.

Damn, I should get onto that sometime.

Re:24 hour charge??

[Eclipse-now]

Of course, "Better Place" have this technology in mind for their fast battery swap system. It's kind of like driving into a car wash but much faster, 40 seconds max. The secret? WW2 bomber bay clips that inspired the quick-release capability of a large heavy battery canister. Coming to Israel real soon. http://www.betterplace.com/

Re:24 hour charge??

[Anonymous Coward]

I just got this somewhat scary image of a dell laptop battery sliding out of the side of a formula1 car. It shouldn't be too big a stretch to expand the idea of swappable battery packs to a much larger scale.

Re:24 hour charge??

[xSander]

That's KERS... the Kinetic Energy Recovery System.

KERS is optional, however. And I didn't count, but I think there's no majority of the cars running it. At least not the team which won 5 of the 6 races run this season so far.

IIRC it'll be mandatory next year.

Re:24 hour charge??

[Chiindi]

You've heard of the worlds biggest ball of string, this is the worlds longest extension cord.

Re:24 hour charge??

[xgr3gx]

I think racing an electric vehicle is the best way to advance the development of them.
Most of the automotive innovation in safety and performance we have today was developed from racing.

In racing, they need to figure out how to get the most range from a battery, how to recharge/replace the battery very quickly, and how to get the sweet spot of power/efficiency to be able to hang with gas race cars.

All of these are very real world problems. Most of us don't need a 4 second battery change, but 5 minutes would be pretty sweet, comparable to refuel.

Re:24 hour charge??

[Anonymous Coward]

Those don't look like air intakes. You can see straight through. It looks more like an attempt to build a F1-shaped car disguised as a Le Mans car, while minimizing the air resistance of the disguise by making the air go straight through it.

Re:24 hour charge??

[kcfoxie]

If I recall the Audi Diesel didn't need to stop for fuel as often. I think the EVs big challenge will be keeping pace with the Audi and Fiat (Puegeot?) Diesels at Le Mans.

Re:24 hour charge??

[SBrach]

Whooooosh Stock car racing is a boring name, how about: National Association of Stock Car Auto Racing.

Re:24 hour charge??

[mattschr]

Ahhh grasshopper. You are confusing electric motors with magic. If an electric motor generated the same torque regardless of speed, what determines the maximum speed of the motor? It would just accelerate until it tore itself apart. It is true that the torque is dependant on the flux and the armature current, but don't forget that if you spin a motor, it begins to also operate as a generator producing back EMF. The back emf works against the flux of the motor, reducing the torque as the motor spins faster. The motor reaches maximum speed when the internal friction and back EMF balance the imput armature current and flux, resulting in zero net torque output. It is true that this torque curve is pretty close to linear as a simplified case, but its not so much torque=X as it is torque=X-K*(RPM) sort of situation. Electic cars will have tons of torque off the line, but will feel less powerflul and suffer reduced acceleration as your speed increases.

Re:24 hour charge??

[BESTouff]

Look, an 800hp gasoline car will deliver rougly 200hp to the wheels, and then only at peak RPM. Whereas a 400hp electric car will deliver 380hp to the wheel, at *any* RPM. Pick your choice.

Re:24 hour charge??

[FreakyGreenLeaky]

American Association of Stock Car Auto Racing of America

There, fixed that for ya.

Grease monkeys are not a bright lot, so they'll like the name. These are the same folks who watch that fake wrestling crap (hulk hogan, et al)... :-D

Re:24 hour charge??

[msi]

Formula One cars have been banned from using any ground effect since 1983 (http://en.wikipedia.org/wiki/History_of_Formula_One_regulations) and must have a flat bottom with a plank (Same Page) although the new diffuser rules are starting to gray these rules. Brabham also had a car with a large fan in the back to suck air from under the car and Lotus had run with side skirts for a number of years to prevent air from flowing under the cars. All of these innovations had been banned in the 1980's for safety reasons, as when they fail the car suddenly has no grip.

Re:24 hour charge??

[mgabrys_sf]

So, is this still "troll tuesday" (whatever the fuck that means to your nerdy little brain) or are you still trying to get the last word in like a person who hasn't seen a woman naked?

I'm guessing the latter of the two - but please - prove me right.

Re:24 hour charge??

[mgabrys_sf]

So, is this still "troll tuesday" (whatever the fuck that means to your little virgin brain) or are you still trying to get the last word in like a person who hasn't seen a woman naked?

I'm guessing the latter of the two - but please - prove me right.

Re:24 hour charge??

[ZosX]

Well sure. These are all just rough ideas. Trust me, I'm not really an expert in electric motors. I just happened to stay at a holiday inn. I was merely trying to explain that actual horsepower is not the number that really matters in the end. Though with gasoline engines it does have some bearing to a lot of people. Where your engine puts the most torque is certainly where you want it to stay. Look at the electric bike that can do 0-60 in one second. That's some serious torque. Especially considering how much more weight it has to lug around. Not much fun when the battery goes flat in 60 seconds or less though.....

Nice car

[PPH]

Pity about that short extension cord.

Re:Nice car

[bFusion]

At least the track is a circle, right? Then you just need to find the radius... maybe a bit of extra slack to make sure.

Re:Nice car

[mdaitc]

no, it's not a circle. it's 8.469 mi long... the main straight is ~3.5 miles long.

Re:Nice car

[GNious]

You MUST be an American...

Re:Nice car

[bFusion]

No, I just have a poor sense of humor... oh wait, that does make me an American doesn't it :(

Looks like PDX's Plasma Boy Racing

[Marxist Hacker 42]

Looks like Plasma Boy and his White Zombie have a competitor out there. (AFAIK, he uses hot-swappable battery packs as well, and only goes full out on the quarter mile).

2x100kW

[Marcika]

Just to point out: TFA must be erroneous or don't know what they are talking about. Two 100kW engines add up to a total of 200kW, i.e. 268hp - far short of the claimed 400hp.

Re:2x100kW

[MyLongNickName]

Based on my almost non-existent understanding of French, it looks like each engine produces 2*100kW. Why it is reported this way, I do not know.

Re:2x100kW

[gubers33]

There is no actual conversion from kW to hp. For example the old Chevy Corvair engine 100kW engine had 140hp. Another thing, engines can be tweaked to had horsepower regardless of the kW.

Re:2x100kW

[gubers33]

Yes, I know 1hp = 746W, but this is a rough estimate.

Re:2x100kW

[WeBMartians]

Hmmm... Maybe "overcurrent" is possible. In other words, 268 hp CONTINUOUSLY and something higher for an insane few seconds. TWO motors? Hmmm... left and right, front and rear, all together...? Also, I thought Le Mans requires a trunk and a tire change. The car is pretty, though. "If it looks good, it'll 'fly' good."

Re:2x100kW

[dmatos]

It looks like a bad Google translation. The original French:

2 moteurs triphasés synchrones de 2 x 100 kW linéaires (2 synchronous tri-phase motors, each 2x100kW linear)

The Google translation:

2-phase synchronous motors of 100 kilowatts x 2 linear

Re:2x100kW

[MyLongNickName]

What are you talking about?

Horsepower's units are feet, pounds and minutes
Watts are Newtons, meters and seconds

All of those units directly convert.

Re:2x100kW

[newcastlejon]

Say what? Isn't the clue in the name: horse power?

Re:2x100kW

[wren337]

Without knowing for sure, I would guess the motors are 100kw rated by the manufacturer, and they're over-volting them by 30-40%.

Re:2x100kW

[vlm]

TFA is even worse than "Sears Horsepower". Take this link for example:

http://www.sears.com/shc/s/p_10153_12605_00970394000P?vName=Tools&keyword=compressor

By some miracle, Sears can pull "1.5 Hp" using "only 8 amps at 115 volts". Truly a miracle of perpetual motion.

So, I figure, using "sears horsepower" they could calculate 200000 / ( ( 8*115) / 1.5 ) = some 326 Sears Horsepower for their little car.

Sears horsepower used to be the absolute peak of scummy non-scientific marketing, second only to "music power" of audiophile amplifiers, but these car guys might set a new low.

Re:2x100kW

[harryandthehenderson]

There is no actual conversion from kW to hp

Yes there are, but it's highly dependent on the context in which you use the term horsepower since it's not an SI unit.

One mechanical horsepower of 550 foot-pounds per second is equivalent to 745.7 watts
A metric horsepower of 75 kgf-m per second is equivalent to 735.499 watts
A boiler horsepower is used for rating steam boilers and is equivalent to 34.5 pounds of water evaporated per hour at 212 degrees Fahrenheit, or 9809.5 watts
One horsepower for rating electric motors is equal to 746 watts

http://en.wikipedia.org/wiki/Horsepower

Re:2x100kW

[discontinuity]

Someone please mod this up.

Re:2x100kW

[neomunk]

Taken from units.dat

# The horsepower is supposedly the power of one horse pulling. Obviously different people had different horses.

ushorsepower 550 foot pound force / sec # Invented by James Watt
metrichorsepower 75 kilogram force meter / sec # PS=Pferdestaerke in Germany
electrichorsepower 746 W
boilerhorsepower 9809.50 W
fwaterhorsepower 746.043 W
brhorsepower 745.70 W
donkeypower 250 W
chevalvapeur metrichorsepower

Seems pretty well defined to me.

Re:2x100kW

[wh1pp3t]

Depends on the specifics of the battery voltage, capacity and current limits as well as physical specifications of the motor. There is no direct 'X kW = Y HP' conversion.

Re:2x100kW

[Marcika]

Yes, there is. Both are standardized measures of power. Read .

Re:2x100kW

[Anonymous Coward]

Or maybe only small horses were available to test the engine?

Re:2x100kW

[NickW1234]

100kW would be 134hp

They're both units of power, so if you were to tweak that engine to 150hp it would be a 112kW motor.

Re:2x100kW

[NickW1234]

Any change in battery voltage will affect both figures proportionally.

they're simply different units to display the same thing.

It's no different than saying I way 220lbs, or 100kg but there's no direct conversion because it depends how much I eat.

Re:2x100kW

[NickW1234]

Yes, I think you're probably correct. They bought a pair of 100kW motors, and set them up with sufficient cooling to run them 49kW over spec.

Either that, or some one's pulling numbers out of their ass, and saying it's as fast as a 400hp engine due to electric motors wide torque curves. I really hate when people do that to things that aren't linear. To be fair, it's often journalists misquoting a tech who's making an off-hand estimate.

2 x 100kW != 400 HP

[Anonymous Coward]

Subject says it all, well almost.
100kW == 134HP

Re:2 x 100kW != 400 HP

[twiddlingbits]

Twin 100kW motors so 268HP. No metion of how many sets of twin 100kW motors. If it only hits 171 then it's going to have to get out of the way of the Prototypes like Mercedes and Audi who can hit 250 on the Mulsanne. Don't expect it to have a podium finish. But still impressive if the car lasts 24 hours. Lots of things can and do break.

Why not say the torque rating?

[Anonymous Coward]

I wish electric car articles would stop publishing the power (kW,HP) rating of motors.
.
The real measure of an electric machine is its continuous torque (Nm, Ft lbs) output which relates directly to mass of the machine. To get a high HP number you can take any motor and just run it really fast. Torque is not perfect, but better than power ratings.
.
Side note: 0-60 mph in 4 seconds flat. Ummm ... doesn't the Tesla Roadster do it in sub 4 and its a consumer vehicle ... just a thought

Re:Why not say the torque rating?

[Rei]

Ummm ... doesn't the Tesla Roadster do it in sub 4 and its a consumer vehicle ... just a thought

Yeah -- the standard Roadster does 0-60 in 3.9 seconds, and the Sport version 3.7 seconds.

Re:Why not say the torque rating?

[hardburn]

Side note: 0-60 mph in 4 seconds flat. Ummm ... doesn't the Tesla Roadster do it in sub 4 and its a consumer vehicle ... just a thought

Yes, and the Wrightspeed X1, based on the Ariel Atom, does it in just over 3 sec.

Then again, straight acceleration isn't the most important thing in an endurance race. Audi has been cleaning up the big endurance races of late with their diesel engine, not by being the fastest, but by good team strategy and needing fewer pitstops for fillups.

Re:Why not say the torque rating?

[MartinSchou]

It's not so much the refill pitstops that made Audi win all those times. The fact that their cars have far fewer techincal problems (i.e. engine or gearbox failures etc) means that they don't have to spend nearly as long in the pits.

Compare the Audi R10 TDI with the Peugeot 908 HDi and you'll see that the 908 is quicker, is almost as fuel efficient (I think they pitted every 13 and 12 laps respectively), and the 908 would have won if it was more reliable. The R10 won with a margain of 4 minutes and didn't win with a lapping of the 908.

Tom Kristensen told TV reporters before the race started, that they wouldn't beat the 908 or speed (they were consistantly 3 seconds slower per lap) or fuel efficiency (that'd be made up with the faster 908), but simply on endurance. That and the fact that his team was consistantly faster during the night - a discipline that Tom excels at, and one of the reasons he's won Le Mans 8 times out of the 12 he's competed - would be 9 out of 12, if his team mate hadn't crashed after the car lost a wheel. It wasn't Capello's fault - I doubt anyone could have kept that car running to the pits after that.

2 x100KW != 400HP

[phatvw]

1KW ~= 1.34 HP
200KW ~= 268HP
400HP equivalent?
They need to explain that a bit better in the article and on the product website

Re:2 x100KW != 400HP

[Fozzyuw]

They need to explain that a bit better in the article and on the product website

So... that's how it works. I wonder if this is the graphic illustration the engineer use to sell the product?

Re:2 x100KW != 400HP

[breeze95]

1KW ~= 1.34 HP 200KW ~= 268HP 400HP equivalent? They need to explain that a bit better in the article and on the product website

I don't think it's a literal conversion. Perhaps the performance of a 200KW motor is equivalent to a 400 HP piston driven motor. As someone who was into drag racing many years ago I can tell you from experience that you need about 400 HP motor to push a 2400 pound car from 0-60 MPH in 4 seconds. If a 200 KW electric motor can do 0-60 MPH in 4 seconds then that is equivalent to a 400 HP piston driven motor.

Re:2 x100KW != 400HP

[NickW1234]

If a 200 KW electric motor can do 0-60 MPH in 4 seconds then that is equivalent to a 400 HP piston driven motor.

It's only equivalent in the situation where you're just going from 0-60, and don't care about distance traveled, etc.

take those same two "equivalent" motors, put them in the same body, and race them for top speed on the salt flats. The 400HP piston motor will win easily.

look instead at the 0-30 time, and the electric will probably kill the piston engine.

I think you're probably correct that that's what they're doing, but it's just plain wrong.

more tech possible with electric

[RichMan]

There are potential technology applications that could really enhance performance.

a) regenerative braking to store power would extend fuel performance even if regular fuel performance was identical to regular car. draw back would be battery cost. Best performance would be small quick draw thin film back to absorb curve braking and allow additional out of curve power spike

b) independent 4 wheel drive. a lot of electronics required but would be able to improve road grip and reduce tire wear

I don't see electronics, drive or breaking mentioned in the article.

Re:more tech possible with electric

[ickleberry]

independent 4 wheel drive

http://en.wikipedia.org/wiki/Lightning_GT

New math?

[Gonzo_Warrior]

Umm ... 200 KW is slightly less than 270 English hp (or slightly more than 270 Metric hp), not 350-400 hp.

Jack Bauer

[clang_jangle]

If they're calling the car "Twenty-4", will Jack Bauer be driving it?

Re:Jack Bauer

[Chris Mattern]

Jack Bauer can go from zero to 60 in 0.1 seconds. He does not need a car to accomplish this.

Re:Jack Bauer

[twiddlingbits]

Chuck Norris can go from Zero to 60 in 0.1 seconds. He does not need a car to accomplish this. Fixed it for ya.

Re:Jack Bauer

[dogeatery]

No, he's busy trampling the other drivers' 4th Amendment rights

Re:Jack Bauer

[Anonymous Coward]

Jack Bauer can go from zero to 60 in 0.1 seconds. He does not need a car to accomplish this.

Chuck Norris, however, can simply be moving at 60. He does not need to accelerate. But if he ever wanted to, he would simply stand still and roundhouse-kick the planet.

Not that impressive

[Rei]

The hideous Eliica already exists and blows it away, the Wrightspeed X1 toasts it at least on accel (and the economy-canceled production model, the SR-71, was expected to be able to beat a Bugatti Veyron in 0-60), while Shelby Supercars is working on the Ultimate Aero EV which should blow them all away.

Re:Not that impressive

[Daniel_Staal]

How well do any of them do when running for 24 hours straight? The Le Mans is designed to test reliability of the cars as well as their speed.

It's one thing to be able to run the shortest lap time. It's another to put in the most laps over a long period of time. Different design criteria, different cars.

Spaceball?

[Rhubarbe]

May the Schwartz be with you

Old tech.

[Anonymous Coward]

This has been done among Universities for several years. If I remember Ohio State and Oklahoma won a lot of the races with these cars.

http://evri.ou.edu/lightning/specs.php

The races were short, it could only run for 8-10 minutes depending on the load without changing battery packs. A quick release mechanism was designed where all 32 batteries could be changed in 10-13 seconds.

Heat Problems?

[icebike]

Why the big air scoops on this car? Do they have a heat problem? They almost look like they are placed for tire cooling more than anything else.

You would think that they would try to make this the sleekest wind-cheatingest car they could instead of grabbing huge chunks of air.

Re:Heat Problems?

[fiannaFailMan]

Why the big air scoops on this car? Do they have a heat problem? They almost look like they are placed for tire cooling more than anything else.

You would think that they would try to make this the sleekest wind-cheatingest car they could instead of grabbing huge chunks of air.

Wind-cheating? The purpose of race car design isn't to reduce drag, the purpose is to generate maximum downforce.

Re:Heat Problems?

[RingDev]

You hit it, the cooling is for breaks and tires, as well as down pressure.

Every once and a while in the NASCAR races they'll show you a camera view from inside the wheel well. You can see when the driver hits the breaks the rotors literally become red-hot from the friction of trying to slow the car down.

Now imagine that same situation, with wider tires and faster speeds on tracks with significantly more braking.

Odds are though, that the frame they are starting with is from some company that produces frames for indy or some other circuit cars. Just as the Tesla Roadster is actually a Lotus frame and body. So the cooling requirements will likely vary significantly from the function of the imaged vehicle.

-Rick

Re:Heat Problems?

[icebike]

Which none of those scoops would do.....

So again I ask....?

Re:Heat Problems?

[will this name work]

Technical regulations regarding the dimensions and shape of the car perhaps. The car looks like it is an open wheel monocoque that has been covered up. I'm not sure about this but I don't think open wheel designs are permitted in Le Mans.

Re:Heat Problems?

[Myrv]

Two Possibilities:

1) They're for the brakes. Their configuration seems to support this possibility. Brakes on F1 or Lemans or similar cars will glow red hot on some corners making brake cooling a priority. Of course assuming they use some form of regenerative braking the load on the brakes should be reduced which brings us to:

2) Electric motor cooling. 100kw electric motors will get quite toasty if not cooled.

Re:Heat Problems?

[Daniel_Staal]

Actually, since they are shown in both up an down positions, my bet is that they are air-brakes, supplementing the regular braking system.

Re:Heat Problems?

[need4mospd]

This car didn't have any problem winning the race last year with MUCH smaller scoops.

Re:Heat Problems?

[Molochi]

Aren't variable aerodynamics banned, though?

Re:Heat Problems?

[Anonymous Coward]

Which none of those scoops would do.....

So again I ask....?

Because motors generate heat, which will melt the motor if it is not dissipated.

And with an electric motor, you can run it waaaaaaay over its maximum output, provided you can keep the thing cool enough not to fuse into a pile of slag.

My guess is that the motor is entirely air-cooled.

Re:Heat Problems?

[Daniel_Staal]

There have been cars with air brakes in the Le Mans before (in fact, they were introduced there), although the rules may have changed since then. And depending on the exact definition, air brakes may or may not count as variable aerodynamics: They intend disrupt the aerodynamics, not change it into a new form.

Re:Heat Problems?

[Anonymous Coward]

Nah, gotta look a bit better. It's basically an open wheeler but they want to enter a GT class, so it can't be.

Re:Heat Problems?

[Anonymous Coward]

Looks like they are straight through holes. What can be more "wind-cheatingest" than that?

Who cares abou archaic measurements like hp anyway

[Colin Smith]

I mean god, lets all get into the 19th century already people.

Also... It's The Torque Stupid
And 0-60 in 4 seconds is slow anyway...

HTH etc

Racecars?

[dedazo]

Why not develop a car normal people will actually buy and use? This is interesting but I don't think we have the luxury of trickle-down innovation at this point, seriously. Just start building the damn things in an industrial scale so a sizable portion of vehicle-bound humanity can start moving to them, FFS!

Re:Racecars?

[Rei]

What would you call "an industrial scale"? I've been reading over market research on electric vehicle forecasts for a business, and they're all over the board. However, it's safe to say that almost everyone is calling for them to be in at least "sizable" numbers by 2015. The most extreme forecast I've come across is Wintergreen's, which is, if I recall the numbers correctly, 32.7 million shipped by 2015. I find that number a bit hard to believe, but on the other hand, when there's perhaps three dozen marques planning to build them in 5 to 6 figure quantities per year within the next few years, some of the lower-end figures are equally hard to believe as well. I tend to favor an 8 million shipped by 2015 scenario.

Still a fairly small percentage of global sales, but a relevant number.

Re:Racecars?

[icebike]

Why not develop a car normal people will actually buy and use? This is interesting but I don't think we have the luxury of trickle-down innovation at this point

I disagree. We don't have the luxury of dumping millions of ill-thought out poorly designed cars on the market without adequate testing to ensure they won't all be clogging out junk yards with huge disposal problems of toxic battery components due to premature failure.

We do NOT have an electrical grid that can support all the new electric cars you would love to see. Sorry, its just not there, and not likely to be there for several decades.

We must go slowly on grid-charged cars until we can double our electrical generation capacity, and beef up the distribrution system.

Race technology has always lead the way in the automotive industry. How else can you get worst case scenario testing in the real world.

We DO NOT have to rush into deployment of half baked technology on a mass scale. We DO have the time to do this right. The end of the earth is NOT upon us.

Re:Racecars?

[Endo13]

Well, currently there's a lot of stigma about 100% electrical cars. Many people (potential customers) believe that completely electric vehicles must necessarily have at least one of the following weaknesses due to limitations with electric engines in cars:

A.) Too slow

B.) Incapable of driving very far

C.) Requiring too much time to refuel

D.) Too fragile

I would think that making one that can compete well at the 24 hours of Le Mans would go a long way toward changing those perceptions.

Re:Racecars?

[osu-neko]

Why not develop a car normal people will actually buy and use?

The false dilemma strikes again!

(People ARE developing cars normal people will actually buy and use. They're also doing this. And they're researching cancer, working on making safer buildings, working on making tastier snack food, and a million other things too. The fact that they're doing all these other things does not mean they aren't working on normal electric cars. "People", being a large number of individuals, are capable of working on many different things at the same time.)

Re:Racecars?

[wh1pp3t]

Historically, developments in racing technology do come to consumer products. For example, semi-automatic transmission (paddle shifting) used in F1 is now common (either paddles or tip-tronic) in many production cars.

Re:Racecars?

[mhortman]

Why not develop a car normal people will actually buy and use? This is interesting but I don't think we have the luxury of trickle-down innovation at this point

I disagree. We don't have the luxury of dumping millions of ill-thought out poorly designed cars on the market without adequate testing to ensure they won't all be clogging out junk yards with huge disposal problems of toxic battery components due to premature failure.

We do NOT have an electrical grid that can support all the new electric cars you would love to see. Sorry, its just not there, and not likely to be there for several decades.

We must go slowly on grid-charged cars until we can double our electrical generation capacity, and beef up the distribrution system.

This is one of the great things about electric cars is that we do have the grid. See electricity is cheaper at night because a.) There is less demand. b.) The supply in most places way surpasses the demand at night because you cannot shut down a coal fired power plant for night time hours. So electric companies are now trying to figure out how to charge one daytime rate, and one much cheaper nighttime rate.

Re:Racecars?

[Anonymous Coward]

I couldn't agree more. The push for green car technology will only serve to hasten the demise of the U.S. auto industry, while doing little eliminate toxic waste. Ignore those who claim to be able to predict the future. Last time I checked, no one had a crystal ball.

Re:Racecars?

[VORNAN-20]

From previous: We do NOT have an electrical grid that can support all the new electric cars you would love to see. Sorry, its just not there, and not likely to be there for several decades. This is a correct statement and IMO the best argument for investing in distributed solar (rooftop panels) I have ever seen. I know it will not pay back for a number of years but it does pay back for most locations in the US. There are even companies that will let you lease their solar cell panels on your roof in return for a long-term commitment. There are also juicy Federal (US) subsidies on the horizon. Somehow or other I think this will happen for ordinary folks. And as a longtime geek, the thought of an all-electric Le Mans strikes me as a good thing, there should be some sort of relationship between the race cars for a race like that and the cars that ordinary people drive. Maybe if they let Danica Patrick drive (she placed third at Indy this year) an electric car could win IF the rules gave them a chance. For racing of course you don't worry about the long term, just get your car across the line first.

Re:Racecars?

[andy_t_roo]

you forgot A*) Too expensive ...

Re:Racecars?

[ThosLives]

The grid has a whole has enough capacity to be sure. The question is, does your neighborhood substation have the capacity to handle charging?

Re:Racecars?

[mhortman]

That is my point, the substation which would normally handle Air Conditioners, and lights galore would be able to handle charging these things easily during the night because the normal daily usage does not happen at night although the supply is still present.

What powers this thing?

[ickleberry]

Ultracapacitors would be ideal for a race, but I suspect nasty Lithium Ion batteries that die after a couple of years. Either way TFA doesn't say.

What about SSC?

[crackervoodoo]

I guess I'm missing something, but how is this the most powerful all-electric when the Shelby Aero EV boasts a 1,000 HP? http://www.shelbysupercars.com/news-012209.php

slow

[pezpunk]

0-60 in 5 seconds and top speed of 171? that's about the same performance numbers as my family sedan (a chrysler 300C SRT-8) which is DECIDEDLY not a supercar! i did not know my 5-passenger luxury sedan was a viable candidate for lemans.

Re:slow

[drinkypoo]

Whatever it is, you probably couldn't race one "continuously" for 24 hours and I about guarantee that it handles like dogshit compared to an actual LeMans car.

Re:slow

[pezpunk]

do lemans cars get pit stops? if so i see no reason it couldn't. handling, of course, is about what you'd expect from a 4000lb car.

but my point was 0-60 in 4 seconds and 171mph is not supercar territory, unless this is 1986.

Re:slow

[drinkypoo]

The acceleration is fine; most supercars do not have the best possible acceleration because it would interfere with top speed (e.g. gearing issues.) The top speed, however, is less than 200 mph, which is pretty much mandatory for a supercar today.

Re:slow

[Krneki]

Until you try to corner with you little bus. And it was 4 sec not 5.

Re:slow

[dennypayne]

"Dogshit" is a pretty apt description for how those handle...I had one as a rental last week (not an SRT-8 though). The SRT-8 Challenger handles worse than dogshit though. (Too bad, it's a great looking car).

Re:slow

[msi]

Family cars should do better at 24 hours races for reliability than the LeMans cars as they are designed to run for years not 24 hours and a few minutes their down side is that they are not fast enough.

my thoughts

[jaimz22]

As far as the motors making 350 - 400 hp, it's totally plausable. If you're simply doing a unit conversion from kW to HP you're doing it wrong Hhe HP rating you're getting from that conversion is electrical horsepower, not mechanical. You have to put this thing on a dyno to get the true output in mechanical horsepower. it's not as simple as doing a mathematical conversion from one unit to the other. And as far as they aerodynamics, I'm sure that they designed it to be as aerodynamic as possible. Yes the tires do need cooled down, any race in that car for any amount of time would create vast amounts of heat on the tires causing them to run slower than they could with cooler tires. I'm not going to explain why that is. if you want to know look it up. OVERALL I'm not impressed. The Tesla Roadster is faster, and more available. SOOOOOO.... I don't see any need for these guys to toss around words like 'Les Mans' because that's just not in THIS car's future. maybe something based on this. but not THIS car.

Re:my thoughts

[twiddlingbits]

Tire heat has nothing to do with it. The tires are designed to handle the heat if properly inflated with Nitrogen. Remember these are racing tires, built for much different use than passenger tires. The intakes are to cool either the motors or brakes or both and probably some air to the driver's cool box. Perhaps there would also be some amount of downforce, you would have to see the bottom of the car to know for sure.

That's still a lot of power...

[TheLink]

If the car stores enough energy to run at full power - 200 kilowatts for one hour, that's a lot of energy you need to transfer in a short time. To transfer everything in a 1 sec charge = 720 Megawatts. 10 seconds charge = 72MW. 100 seconds charge = 7.2MW.

Even if you halve the power to 100kW (say the car only goes 50% power on average), those are quite big numbers. Who wants to be sitting in the car while 36MW flows into it?

The transfer is unlikely to be 100% efficient so there will be waste heat generated. 1MW of waste heat is no funny.

If you're going to use supercapacitors or batteries or fuel cells, you'd be charging/filling them outside the car, and then plugging them into the car and hoping they don't blow up in the process (it's still easier to make safer than pumping megawatts of electricity into the car).

Re:That's still a lot of power...

[Rei]

If the car stores enough energy to run at full power - 200 kilowatts for one hour

1) Kilowatts is energy, not power.

2) If you meant kilowatt hours, driving doesn't work that way. Even in racing, you never use your engine at 100% full power 100% of the time. In a race like this, you're not even going to be close to that. The energy this car expends accelerating to speed will be 2/3rds recovered on braking, as in the Tesla Roadster. The rest of your losses are aero and rolling -- primarily aero. Apart from the standard CdA issues, aero losses in this car will be conditional on how much downforce they design for and what sort of speeds they're dealing with.

And a one second charge? Heck, if you really want to create ridiculous numbers, require that they charge in 0.001 seconds! ;)

and hoping they don't blow up in the process

"Blow up"? Give me a break. These things aren't made out of explosives. Heck, supercapacitors generally aren't flammable at all, and your non-cobalt-based li-ions are certainly less flammable than gasoline. The worst thing you risk during a pack change is arcing -- but unless you're an idiot, you have breakers on your pack that get closed before swap and opened after.

Re:That's still a lot of power...

[Jeffrey Baker]

1) Kilowatts is energy, not power.

Fail.

Re:That's still a lot of power...

[Rei]

I shuold porffraed beter. :P

Re:That's still a lot of power...

[TheLink]

0.001 seconds is ridiculous.

But 1, 10 or 100 secs out of 1 hour of racing are not ridiculous numbers for "racing pit stop" work times.

As for arcing, lightning is mere arcing. It's just typically hundreds of megawatts and does blow stuff up from time to time. Like I said, 200kWh in 1 second = 720MW. And 720MW = "Bang!". Maybe they've worked out how to ensure that'll never happen. If they have, I'd be interested to know how they did it.

Perhaps that race tech might end up being used in laptops and phones ;).

Re:That's still a lot of power...

[Rei]

But 1, 10 or 100 secs out of 1 hour of racing are not ridiculous numbers for "racing pit stop" work times.

10 seconds is an order of magnitude less power than you stated.
100 seconds is two orders of magnitude less power than you stated.

You deliberately skewed the numbers by choosing only one second to do the charge in. Hence my point, that if you're going to deliberately skew the numbers, you might as well go all the way.

As for arcing, lightning is mere arcing. It's just typically hundreds of megawatts and does blow stuff up from time to time.

No, the average power of a lightning strike is about 1 terawatt, and the only primary "explosions" it ever does are flash boiling which -- if in a very confined space -- can fracture what is confining them.

Re:That's still a lot of power...

[TheLink]

> 10 seconds is an order of magnitude less power than you stated.
> 100 seconds is two orders of magnitude less power than you stated.

Go read again. I gave values for 1, 10 and 100 seconds in my original post. I guess you prefer to concentrate more on arguing with people than on figuring out what they are trying to say (or actually say).

Yes you're right about the lightning values, and I'm wrong about it - I got my figures from an incorrect source.

But if you don't think 200kWh could blow stuff up, fine. Meanwhile I hope the race car people think different and take enough precautions.

Re:settled by Wolfram

[xZgf6xHx2uhoAj9D]

WTF are you on about?

Re:settled by Wolfram

[Marcika]

To reiterate MyLongNick:

hp = ft * lbs / min

W = N * m / sec

All of these units convert directly. I call your Wolfram and raise you a Google.

Re:settled by Wolfram

[Anonymous Coward]

Huh?

http://www30.wolframalpha.com/input/?i=25+horsepower+to+watts

Re:Who cares abou archaic measurements like hp any

[DamnStupidElf]

I can apply hundreds or thousands of foot pounds of torque by standing on a long lever. However, I cannot produce more than about .09 horsepower for any length of time. Uniform torque through the power band is important for good acceleration unless you have a continuously variable transmission, but other than that the maximum power and efficiency is what matters (and motors are far better at providing constant torque than internal combustion engines). 0-60 in 4s is rather slow for a supercar, but if it can maintain a higher efficiency by regenerative braking it may have a chance. Electric motors can usually handle 150-200% of their rated power for short bursts, like accelerating out of a turn using the energy regenerated from breaking coming into it.

They need at least 800hp.....

[KPexEA]

1) They are way underpowered, even compared to the 2008 front runners.
2) There currently is NO electric car class at all
3) LeMans is by "Invitation only", not just anyone can show up and race.

~2008 specs for the front runners:

Audi R10: 650 hp-1100 Nm-925 kg
Peugeot 908: 700 hp-1200 Nm-925 kg

And The Price Is : +1, Informative

[Anonymous Coward]

Probably around U.S. $200,000. I can see these vehicles for sale at Walmart,
after I had ingested LSD.

Yours In Socialism,
Kilgore Trout

171?

[spoop]

171 mph top speed jumps out at me as very uncompetitive at Le Mans. The Circuit de la Sarthe is a long track with a lot of straights, especially the Mulsanne Straight. Last year, the cars in the GT2 class which I assume this will compete in (the slowest class) topped out at 182-186mph for the most part. Source: http://auto-racing.speedtv.com/article/le-mans-radar-trap-speeds-and-corners-speeds/

Re:171?

[need4mospd]

I thought they might try to make it up with a respectable 4 second 0-60 time. But I'd be wrong. The Ferrari F430GT in the GT2 class does it in 3.2 seconds. They've pretty much got no shot, but it's still pretty cool to try.

Re:settled by Wolfram

[neomunk]

neomunk@laptop:~$ units
2445 units, 71 prefixes, 33 nonlinear units

You have: horsepower
You want:
        Definition: ushorsepower = 550 foot pound force / sec = 745.69987 kg m^2 / s^3
You have: watt
You want:
        Definition: J/s = 1 kg m^2 / s^3
You have: horsepower
You want: watt
        * 745.69987
        / 0.0013410221

You're not comparing newtons to horsepower, wherever did you get that idea in the first place? You forgot the meters and seconds parts of the equation.

Fastest?

[teoryn]

"...the most powerful electric race car ever built."

Maybe for a certain class of race car, but The Buckeye Bullet broke 300 mph years ago, and the new model will have been tested before this Green GT car is built.

So when's the family care endurance race?

[GodfatherofSoul]

I haven't followed the research closely, but it seems like the majority of stories are about high-end electric race cars when the real money would be in much more modest family sudans or commuters. I'd love to see an endurance racing challenge where manufacturers had to hit real-world benchmarks (hauling around mom, kids, and groceries equivalent in weight for X miles or X hours).

Re:So when's the family care endurance race?

[Qzukk]

endurance racing challenge

Every 15 minutes the driver will have to announce whether or not they are there yet?

Numbers

[Anonymous Coward]

400 horse electric would be very competitive with 800 gasoline. probably more than competitive. I am sure there are some EEs here who can explain it better. Right off the bat the torque is simply going to be amazing on the electric side. In fact I would doubt there would be any cars there on the gasoline side who would have near as fast acceleration no matter what speed or gear they might be in. The electric is going to be much faster in most of the slowing down and speeding up parts of the race. Only on the flat out straights will the gassers be competitive.

Need to change the LeMans Race Rules

[Anonymous Coward]

LeMans will have to add a new classification.

The LeMans rules were updated to allow for Hybrid vehicles within the current car classifications. http://www.racecar-engineering.com/news/people/282760/le-mans-2009-2011-regulations-released.html It looks like the focus of using a hybrid in this case is energy recovery from braking, which would improve overall mileage. They specifically disallow storing lots of energy with the goal of improving power. In fact, the total stored energy from the regen system can not exceed 1MJ (for comparisn a gallon of gas is 121 MJ).

Re:Who cares abou archaic measurements like hp any

[smellsofbikes]

I don't mean to nitpick, but it's possible for a human to produce a *lot* more than 0.09hp for quite a while. In the 1989 Tour de France final time trial Greg LeMond produced roughly 2/3 horsepower continuously for just under an hour. I'm not of that caliber but I can crank out just under a third of a horsepower for over two hours if I'm feeling really motivated, according to an on-bike dynamometer.

While I'm on the subject, humans have pretty good torque characteristics, similar in shape to a steam engine's: flat up to about 90-120 rpm (depending on training) and then dropping off towards zero fairly quickly.

Some electric motors have their max torque at 0 rpm, dropping linearly to zero torque at their max rpm, but others have sigmoidal or other odd torque/rpm curves; compound-wound and series-wound motors diverge (in opposite directions) from standard dc motors (if I remember correctly.)

EESTOR

[WindBourne]

If EESTOR was for real AND has produced prototypes, now would be the ideal time to bring it out for use. Put it in a decent car and see what happens.

Re:Nice, SLOW, ILLEGAL car

[Motard]

A magical extension-cord-of-stretching would be the only thing that might give this car a shot. 400 HP is ludicrously low for a Lemans Prototype (LMP). They don't mention the weight of the car.

In addition, the car as shown would not be permitted. All cars running in the 24 must be 2-seater sportscars. While anyone would chuckle considering how a passenger would actually fit in an LMP, they clearly have some minimum allowance while the pictured vehicle is clearly a one-driver-in-the-middle car.

The rear wing design shown is clearly suboptimal if you look at the innovations on real LMPs. The design would be really cool for a Batman movie, but otherwise, it seems clear that it was designed by students and not ready to go up against really highly paid engineers.

Oh, and those five students (or their PR dept) might want to refer to a summary of the 2011 ACO rules for Lemans Protypes: http://www.lemans.org/sport/sport/reglements/ressources/2009/auto/reglement_2011_moteur_hybride_gb.pdf

Ooops. Too slow, not legal. Total BS.

Re:Can't run in GT2

[Motard]

Unless they have dealerships in place for 2011, they can't run in a GT class. This concept is illegal for all classes however...

http://www.lemans.org/sport/sport/reglements/ressources/2009/auto/reglement_2011_moteur_hybride_gb.pdf

Cancel nitpick: PP is right.

[smellsofbikes]

For an hour or two, well over half a horsepower is possible, but for 24 hours (as the race in question) it looks like 0.1hp is typical of results seen in the Race Across America.

0-60 in 4 seconds?

[Radfahrer]

Umm... the Tesla Roadster can do 0-60 in 3.9 so all they need to do is add a third gear to get better top speed and they've got this beat... I'm not impressed.

Will it run Linux?

[Anonymous Coward]

so will it?

Dawson is an idjot

[cdn-programmer]

twin 100 kW motors = 400 HP?

What an idjot.

This is actually about 268 HP.

http://en.wikipedia.org/wiki/Horsepower

Its pretty bad when they can't even do the basics.

Trust them?

[cawpin]

Do we really trust a company that can't do a simple conversion?

100kW ~ 134-135 hp (depending on hp standard)

2 x 100kW ~ 270hp

270 =/= 400

Re:Can't run in GT2

[CorporateDrew]

Unless they have dealerships in place for 2011, they can't run in a GT class.

Assuming Green GT isn't going to have a model in the dealerships by 2011, then doesn't that mean they'll have to run in the LMP2 class against the Spyders, Acuras, and the Lolas?

Re:Can't run in GT2

[Motard]

In fantasy-land, yes. Only their car isn't legal for any class. And it wouldn't be competitive for any class.

It is total BS.

Why does this make me think of ....

[3seas]

Hot-Wheel cars?

Re:Who cares abou archaic measurements like hp any

[Jaime2]

You're a moron. Torque is only a useful measurement if you fix all of the other variables. Horsepower is always a useful measurement.

Example: I can make an cheap Chinese corless drill make 1000 ft-lbs of torque simply by adding a reducing gear. 1000 ft-lbs of torque is only really meaningful if I first give the rpm at which that torque needs to be made. On the other hand, that Chinese drill is never going to make 1HP. Think of HP as the ability to create torque.

Oh.... I agree that 0-60 in 4 seconds is nothing to write home about. My streetbike does 0-60 in about 2.3 seconds. Gotta love 199.1 HP in a 400 pound package.

numbers don't add up

[Anonymous Coward]

If the power output of those motors is 100kW, and there are 2, then the total power output is 200kW, or 200,000 watts. There are 746 watts per horsepower (listen to me now, or look it up for yourself and believe me later). 200,000 watts, divided by 746 watts per horsepower gives 200000/746 = 268.09651474530831099195 horsepower. (268 horsepower). Not bad, but not 400.

400 HP @ 2x100kW = thermodynamics violation

[Phreakiture]

Horsepower is a measure of mechanical energy. Kilowatts are a measure of both mechanical and electrical energy. Kilowatts of mechanical and electrical energy are freely interchangeable, i.e. it is a given that a motor that develops 100kW uses 100kW plus some (hopefully) small overhead, but under no circumstances does it use less than 100kW.

You cannot develop 400 HP with two 100kW motors. 100kW is 134 HP, hence two 100kW motors can produce, at most, 268 HP.

I think this is akin to the claims of 5 HP on some power tools -- yes, if you had the motor developing its maximum torque while running its maximum speed, it would, indeed, develop that. Unfortunately for the liars who concoct these figures, maximum torque is at near-minimum speed, and maximum speed is at near-minimum torque. Maximum output can never exceed maximum input, no matter what.

Now, it seems like they've got a cool idea here, so why cloud it up with bullshit?

Re: Electric Draggsters

[Anonymous Coward]

I bet the advantage of having no clutch to worry about helps a lot in this.

1) Hold wheel strait
2) Push the pedal all the way down when the light turns green

Yeah I can see that being easier than gaining the skill to shift up through the gears in an optimal fashion.

Don't emphasize "slowly" and you're dead right.

[Anonymous Coward]

I agree with everything you said, but I would replace "slowly" with "intelligently". At this moment in time those are the same thing, but tomorrow or the next day - they might not be.

Still, your major point can't be said too many times; if we rush into any global initiative with little or no planning we're unlikely to succeed. That would be like sending huge armies to a 3rd world nation without planning on what to do after the fight! This sort of technology needs to get repeatedly beaten to death on the race track, ASAP!

Quick?

[anotherslashfan]

Anyone notice that their "supercar" isn't as quick as the Tesla Roadster (0-60 3.9 secs)? It definately has Tesla beat in top speed. Perhaps "quickness" isn't a big deal for Le Mans-type racing? http://www.teslamotors.com/

Re:Who cares abou archaic measurements like hp any

[DamnStupidElf]

How was the power output of 2/3hp actually measured? Estimating it based on speed, an estimate of wind speed, and an estimate of drag could lead to some inaccuracy. I'd believe the dynamometer more, to be honest. Does yours measure real wheel power via motor resistance or some other method?

Re:Who cares abou archaic measurements like hp any

[smellsofbikes]

It was estimated based on his known drag (from wind tunnel tests.)
What I've used is a Powertap hub that has a calibrated strain gauge integrated into it.

(and in case you didn't read my other reply, it was based on 1-2 hours, not 24, as in the story, and for 24 hours, it looks like 0.1hp is dead on the money, so you're completely right in your estimate.)