$10 million X prize for 100 mpg car
 

https://progressiveautoxprize.org/

Think a group of us could win this prize? Do we know enough to do it? Do any of us have the means to even think of building something to compete?

From what I've read, there are 2 categories. Here's the criteria for the "main":

minimum top speed = 100 mph,
0-60 in at most 12 seconds,
room for 4 adults and 10 cubic feet of cargo space,
4 wheels,
meets safety standards,
economical to build,
and features such as climate control and stereo sound system.

And they want to hold races in 2009.

Now the first thought I had was that I didn't see anything saying that the 4 adults have to be seated conventionally. Sooo... how about a tandem car? Have 4 individual seats all in a line. Perhaps have the backmost seat face backwards.

that seems pretty hard, unless it has a huge lit-ion battery

wait, woa, does it not include a requirement to meet emissions standards? If not, that'd be a cakewalk. Even if it did include an emissions requirement, I think it would be very doable. I'd love to be on a team for that, but finding funding might be a challenge.

Start with a plug in Prius. My choice for an engine would be a 1.0-1.2 liter 3 cylinder diesel That combo should be good good for 80 to 90 mpg for a start.

Prius due to size and aerodynamics. For highway mileage the diesel engine gives the car the extended range and maximum efficiency on the highway. Next I would look at a way to lighten the car by at least 500 lbs. I would look at making the generator as light and efficient as possible. I would want the fastest charging longest lasting battery pack I could find or create. Reason faster the pack charges less time the ICE is running burning fuel.

You're looking at a major redesign for 100mpg to work.

-Super-skinny tires for minimal rolling resistance.
-Smooth, aerodynamic body to minimize drag. Perhaps replace side mirrors with cameras.
-Large Li-ion battery and motor to allow electric assist up to urban and highway speeds.
-Small engine - 1.0L or less

could probably work if-

-use the honda insight body and add 2 seats in back + extend vechicle length
-1.0 liter turbo Diesel, Hybrid
-Skinny tires
-no ac/ps
-driver has to be a skilled hypermiller, since some insight drivers got like 180 mpg on an insight before

Did the rules say the vehicle had to be production ready? Doesn't that mean crash tested, etc.? Kind of a jump in and drive to the store ride? This could be a pretty costly endeavor.

https://progressiveautoxprize.org/aut...aft-guidelines

Page 7 of the draft guidelines says emissions must be at least Tier II Bin 5 (LEV II).

Page 8 says:

Braking: 60-0 in 170 feet or less
Lateral acceleration: 0.70 g skidpad
600-foot slalom @ 55 mph
Maintain 55 mph @ 7.5% grade (or 45 mph for "alternative" vehicle category)
74 dB max sound level

A "mainstream" category vehicle must have at least 10 cubic feet of cargo space and minimum range of 200 miles.

Ugh, my reader doesn't like that PDF at all, so that's all the time I'm going to spend on it at the moment.

Forget about the car for a moment - you need a way more efficient engine to just move that much weight of 4 people around and if it has to meet the safety requirements then add more weight to the vehicle so start looking at super light super strong materials like Carbon Fiber and aluminum alloys. 0-60 in under 12 seconds is faster than my 1980VW Rabbit (15sec) which had about 60hp in a relatively small and light vehicle.

I don't think it will be that tough to build a 100 mpg car. You don't even need high tech stuff like a hybrid.

After all, the VW Lupo diesel already gets 100 km per 3 liters of fuel, or 78 mpg. It's not much of a stretch to 100 mpg with a few conventional tweaks like carbon fiber hoods and doors, spats and wheel covers, LRR tires, and taller gear ratios.