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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!'"
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).
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
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.
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
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
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.
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.
Give a boy a gun and you arm him for a day. Teach him how to make a gun, and the whole metaphor breaks down.
hp = ft * lbs / min
W = N * m / sec
All of these units convert directly. I call your Wolfram and raise you a Google.
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.
+++ ATH0 +++
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/
I blame geof's speakers.
Audi took almost a 1 hour stop for maintenance and still took 3rd.
Fail.
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?
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