The Automotive X Prize, Part 2

Looking over the rules further, it seems to me here’s what will happen. The Alternative class will have a lot more vehicles that succeed than the Mainstream class because the requirements are not as difficult.

Fewer passengers, less weight, fewer minimum wheels, and lower performance requirements for top speed, incline, and range. Three wheelers with two front wheels and one rear driving wheel are going to be all the rage. The reasons are because in the US they are legally considered to be motorcycles, and have far fewer regulatory hurdles to clear (airbags, bumpers, etc).

I’m hoping a few four wheelers will make it just to see if it can be done. But I’m convinced the Alternative class will see the bulk of the vehicles that can meet 100 MPGe.

The concepts behind building cars for any of these classes would likely be as follows:

Massive weight reduction. All vehicles will be very light, especially to climb and accelerate during city driving cycles.

Aerodynamic drag and rolling resistance will have to be minimized, so frontal area and drag coefficients will have to be low. But the rolling resistance will have to be high enough to provide adequate braking and cornering traction for the performance requirements. The necessity of these tradeoffs may result in active devices being used to expand the overall performance envelope.

In order to maximize energy efficiency the propulsion method will also use regenerative braking to recapture otherwise lost energy, and reduce the size of the conventional brakes. If an internal combustion engine is used there will be idle cut off and designs will strive to run at a near constant RPM.

The engine will provide only modest power, and will be assisted during acceleration by additional stored energy such as that saved from regenerative braking. Finally, energy captured from waste heat or solar sources will be used for accessory loads. Vehicles using solar sources would have to somehow hedge against extended dark or overcast periods to ensure adequate energy at all times – most likely using the vehicles fuel source directly as back up.

The Automotive X Prize, Part 1

This competition has been getting a lot of publicity recently, and that will increase as the 2009 Grand Prize Final approaches. I just reviewed the draft rules and it seems to be on heck of a challenge – I’m eager to see what vehicles the competitors will come up with.
By the way, the first X Prize ended up awarding a $10 million prize to the winning suborbital spaceflight team headed by Burt Rutan in 2004.

The premise of the AXP is to “inspire a new generation of super-efficient vehicles that help break our addiction to oil and stem the effects of climate change.” The competition will be a road race with varied drive cycles, terrain and driving conditions.

There are two classes of vehicles. One is mainstream with four wheels and seating for four or more, and used for conventional purposes (how many times can I say 4 in a sentence). The other is alternative which requires a minimum accommodation of 2 passengers (side-by-side, which precludes motorcycles).

Minimum performance for mainstream designs is 0-60 mph in less than 12 seconds, top speed of 100 mph, range of more than 200 miles, 60-0 MPH braking less than 170 feet, 0.70 g on a 300 ft diameter skidpad, a 600 ft slalom speed of 55 MPH, drive-by noise of less than 74 db, and at least 55 MPH on a 7.5% grade.

The requirements are similar for Alternative class designs, the differences being a minimum top speed of 80 MPH, range of 100 miles, and 45 MPH on a 7.5% grade.

All vehicles are required to have minimum safety features such as windshields, wipers, mirrors, lighting, horn, indicators, and brake lights.

Vehicles are to be intended for a 10,000 unit/year production level, competitors will have to produce detailed specifications and a business case.

The Qualifying event will require a minimum of 75 MPGe, and the Grand Prize Final will require competitors to average a minimum of 100 MPGe over the entire event. MPGe stands for Miles Per Gallon of Gasoline Energy Equivalent, “a measure that expresses fuel economy in terms of the energy content of a gallon of petroleum-based gasoline.”

Beyond that vehicles will have to meet a total CO2 emissions requirement of 200 g/mi, and meet US EPA Tier II, bin 5 emissions standards which entails 120,000 mile compliance. Why they are mixing metric and standard units like the EPA I’ll never know, but I digress.

Anyway, 200 g/mi works out to 125 g/km which is close to the 120 g/km figure proposed by for Europe for 2012. But the key difference is that the 125 g/km would include all upstream emissions used to generate the fuel (electricity, gasoline, etc).

Finally, AXP will supply all the fuel during tests and races to help ensure parity. They intend at this time to supply gasoline, diesel, electricity, natural gas (presumably liquid form), biodiesel, and E85. More to follow soon (click here for AXP site).