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I wonder why most people are going electric...it must be the way the rules are set up. I am guessing that diesel engine must be too heavy.

But then again, if you took the latest Polo TDI and rebuilt it with an Aero body made of carbon fiber, then gave it lightweight supporting parts, maybe you could have a competetive car.
 

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I feel bad for the guy with the neon parts. There's so much weight that you can save by using custom composite and aluminum parts. How can they compete with other teams with millions in venture capital?

Electric is probably more efficient. Less transportation costs, etc. Of course, if you're not near an outlet there's going to be problems. If the neon team can make a car with very long range, then I think they could have an advantage. The souped up electric cars will probably win, but the main obstacle is range, IMO.
 

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I've also heard of a hydraulic braking regeneration system instead of an electric hybrid powertrain. The idea is that storing the energy of braking in a hydraulic system is a lot more efficient than storing the energy in a battery.

If you were to take a Polo TDI and build it in carbon fiber with a streamlined body, what kind of mileage can you get? If it weighs 2390 pounds, what kind of weight can you get in all carbon fiber? The engine and transmission would stay, but the suspension, seats, body would all be lighter. Then replace the windows with lexan.

I've seen the rule that every 10% you drop weight you gain 6% fuel economy. So if the CF Polo with an aero body is lets say, 50% lighter and 25% less drag, let's make it equal to 70% lighter. Then you are gaining 42% fuel economy. If the polo can get about 78mpg, then a 42% gain is 110.76 mpg. Not too bad but not even close to the other cars :(
 

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You are assuming that the 10% weight loss=6% fuel economy gain is linear.
It's probably a rough rule of thumb for +20/-20 weight loss but when you are dealing with -70% weight loss, would acceleration take a lot less energy? (disclaimer...it's been a loong time since I took high school physics!)
 

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Lol, yeah, these are just numbers Ive just heard. And the three cylinder Polo TDI engine would be overkill for a 700 lb car. If that electric car/motorcycle that was on teh wired website weighs over 1000, I'm sure the CF Polo must weigh more since the engine and transmission are very heavy. Maybe 1300 lbs for everything?
 

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It's called embodied energy: there is some debate about how accurate the "total" energy for various fuels are but electricity is seen as pretty efficient.

However, carbon fiber is not. Unlike steel or aluminum, carbon fiber can't be recycled.
 

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Hmm...no matter how green you make a car, someone will find a way to trash it. There must be some way to reuse carbon fiber...

The polo engine weighs about 220 lbs. If the transmission weighs (estimated)120 lbs, with the other small stuff that's about 400 lbs that you carry over from the stock polo. You really need to have a car that is about 1000 lbs to be competetive and that leaves only 600 lbs for everything else. I really think that a carbon fiber polo with an aerodynamic body just can't compete with the other cars. You would have to have a 2 cylinder alumimum or magnesium TDI engine, the lightweight aero body, and more, to be competitive.
I remember reading something about a carbon fiber prius concept and found some more info here:
http://www.bloomberg.com/apps/news?pid=20601109&sid=aFSrkKiAyKAI&refer=home

Using existing prius hardward in the CF body, the concept weighs 67% less (and costs 100 times more than steel at current prices), and gets 92mpg instead of 46mpg in the existing prius.

So if you made an identical projection for the carbon fiber polo with stock engine and transmission, you would get about 1200 lbs and 150mpg (rough numers). Pretty good but not even close to the other competitors. Maybe if you went to a lighter engine/transmission and went all out on weight reduction, you could get 1000 lbs and 200-250 mpg but you're no longer using off the shelf components and it's not a carbon fiber polo.
 

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Whoops, I guess carbon fiber can be recycled. Even still, I think that off the shelf components just can't cut it in the auto x prize. That other car was getting 300+ MPGe and it was already a driveable car. I think the 2 passenger car is too tough, maybe a 4 passenger polo might be the "sports car" of the group.
 

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Interesting article. The electric motor on the Aptera makes 50 kilowatts. 50 kilowatt hours is equal to 67 horsepower hours. The polo makes about 70 some hoursepower? The aptera looks pretty sporty already.

I think the real problem is elsewhere, if you can ride a bike, that would fix the issues.
 

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Rde a bike??? What are you, a communist:D

Just kidding, but let's be real. There are a few cities where you can ride a bike, there are a some places where you can ride the bus and take the train. Most places in the US, you need a car to get around. That's just the way the cities and towns are planned.
 

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Lol, no bike's aren't communist. I give up then, until we get a magic car that runs on fairy dust and smiles, energy will just get more and more scarce.
 
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