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??

[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??

[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?

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

[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