Kevin Costner, here's your chance. Sparked by the disaster in the Gulf of Mexico, a well-connected environmental activist is offering $1.4 million for new methods to clean up oil spills.

The Wendy Schmidt Oil Cleanup X Challenge is being funded by, you guessed it, Wendy Schmidt. She's president of The Schmidt Family Foundation and helped get the foundation's 11th Hour Project and Climate Central going. She's also co-founder of the Schmidt Marine Science Research Institute - along with her husband, Eric Schmidt, Google's billionaire CEO.

Schmidt said she was prompted to act by the Deepwater Horizon leak and oil spill in the Gulf, which has created environmental havoc for more than three months.

"With tens of thousands of ocean oil platforms across the globe, and billions of barrels of oil being transported every day by tankers, it's not a question of 'if' there will be another oil spill, but 'when,'" Wendy Schmidt said in today's announcement of the challenge. "We need to come up with better solutions to capture oil on the surface, to minimize the harm these spills are causing to marine life, coastal wetlands, and beaches and to our livelihoods — a harm that can last for generations. This is why I am personally funding this X Challenge: to inspire innovators around the world — and all those who want to help address what has happened in the Gulf — to focus on solutions to an ongoing, systemic problem."

As Schmidt points out, the Gulf isn't the only place that faces oil-spill ills. Just in the last month, devastating spills have occurred in locales ranging from Michigan to China. And it's widely accepted that the technologies for cleaning up oil leaks have lagged behind the technologies for finding the oil in the first place.

So here's the deal, as laid out by the X Prize Foundation, which has added Schmidt's challenge to its portfolio of prizes:

Phase I. From August 2010 to April 2011, teams from around the world are invited to register for this competition, and to submit their approach to clean up oil slicks created by spills or leaks from ships or tankers (e.g. Exxon Valdez) land drainage, waste disposal, or oil platform spill (e.g. Deepwater Horizon). An expert panel of judges from industry and academia will evaluate all of the proposals along the following criteria:

• Technical approach and commercialization plan
• No negative environmental impact
• Scalability of and ability to deploy technology; cost and human labor of implementation
• Improvement of technology over today's baseline booms and skimmers.

Phase II. The judges will select up to 10 of the top teams to demonstrate their ability to efficiently and rapidly clean up oil on the ocean surface in a head-to-head competition. These proofs of capability, which will determine the winner, will take place at the National Oil Spill Response Research & Renewable Energy Test Facility (OHSMETT) in New Jersey. The top team that demonstrates the ability to recover oil on the seawater surface at the highest oil recovery rate (ORR) and recovery efficiency (RE) will win the $1 million Grand Purse. Second place will win $300,000 and third place will win $100,000 in purses.

The money should be awarded around this time next year.

The X Challenge FAQ file says the challenge is focusing on surface cleanup "because we believe that in order to minimize the environmental impact of all oil spills ... we must capture the oil at the spill site. Once the oil hits the shore or is weathered on the sea surface, it is too late. We must have the technologies necessary to stop oil spills at the spill site."

Wendy Schmidt hopes that the X Challenge will capitalize on some of the lessons learned by Silicon Valley ventures such as Google and Apple.

"Silicon Valley has become a culture of venture capitalism that generates new ideas, and competition, and innovation and job creation," she told me today. "With oil, we haven't had that. So with this prize, we look at this as 'pre-venture capital,' if you will. There isn't just one winner in this, even though that's how it's ostensibly set up. There are many winners."

Even before today's official announcement, the contest's backers have received more than 1,000 e-mails asking for more information. They expect 75 to 100 teams to register for the competition.

"Any corporate entity can compete. Companies and non-profits can register to compete. Universities and communities can form corporate entities which can then register to compete. Government agencies are not eligible to compete," the backers say.

The X Prize Foundation has been in charge of four big-ticket competitions, including the Ansari X Prize for spaceflight ($10 million), the Progressive Insurance Automotive X Prize for super-cars ($10 million), the Archon Genetics X Prize for low-cost gene sequencing ($10 million) and the Google Lunar X Prize for moonshots ($30 million). It also ran the Northrop Grumman Lunar Lander Challenge (with NASA providing the $2 million purse).

The foundation said it was making a distinction between its X Prizes (which usually take years to win) and this new X Challenge (which has a smaller purse and a one-year time frame). Despite those differences, the Wendy Schmidt Oil Cleanup X Challenge and the Progressive Automotive X Prize have the same goal: to use cash incentives as an extra lure for environmentally minded innovation.

"The X Prize Foundation is focused on the environment in two ways," Peter Diamandis, the X Prize Foundation's chairman and CEO, told me this week. "First, with Progressive, it's about reducing the consumption of oil. And second, we are pleased with Wendy Schmidt, who is personally funding this, for dealing with the issue of oil spills - not only from platforms, but potentially from tankers. While we have an oil economy, it's naive to think this is the last oil spill we'll have. Finding out ways to much more efficiently clean it up when it does happen is an important objective of that competition."

Just last week, a consortium of major oil companies announced that they would set aside $1 billion to focus on new technologies for containing deep-sea oil leaks. But the X Challenge's backers said this program "will not negate the need for oil cleanup technology" that focuses on surface spills. They said they hoped non-traditional tinkerers as well as deep-pocketed corporations would go after the X Challenge cash.

After all, if a couple of bicycle mechanics from Ohio could figure out how to build a heavier-than-air flying machine, a couple of grease monkeys from heaven-knows-where just might come up with a better way to clean up the oil. And thousands upon thousands of potential solutions to the Gulf oil crisis have been streaming in from the general public over the past three months.

So here's my question: Would "Field of Dreams" film star Kevin Costner, who has bankrolled an oil-sucking invention now being used in the Gulf cleanup effort, be eligible to enter?

"From what I understand of his centrifuge solution, they could be part of a team competing for the prize," Francis Beland, prize director for the X Challenge, said in a forwarded e-mail.

There it is, Kevin: If you bring it, you could win.

More on oil cleanup technologies:

• Video from 'Rachel Maddow Show': Peter Diamandis on X prizes
• Video: Kevin Costner testifies to House panel on Gulf cleanup device
• Video from 'Rachel Maddow Show': Kevin Costner's no crackpot
• The pilots behind the Gulf's robot navy
• Deep water brings more oil and more danger
• 'Super skimmer' a giant bust in Gulf oil cleanup
• House approves legislation on drilling safety and oil cleanup
• Full coverage of the disaster in the Gulf

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The $10 million Progressive Insurance Automotive X Prize competition finished up its final on-track round, and the results are clear: If anyone is going to win the $5 million contest for four-seat cars, it's going to be the Virginia-based Edison2 team. If anyone is going to win the $2.5 million contest for alternative two-seat tandem vehicles, it's going to be the Swiss X-Tracer team. It's only the last $2.5 million - set aside for two-seat, side-by-side cars - that is up for grabs.

Edison2 and X-Tracer are sure things, because those teams have the only cars still standing in each of those contests ... two in each category. The side-by-side contest has five cars entered, and based on a runoff race that was conducted this morning, it looks as if it's down to the Finnish RaceAbout team vs. the Wave II from Nevada-based Li-Ion Motors. Those teams finished the course at the Michigan International Speedway just seconds apart, with RaceAbout leading by a nose.

"Only performance stats will tell who wins the big prize in this category," the X Prize Foundation's Amanda Stiles reported in a Twitter update from the race track in Brooklyn, Mich.

The final results aren't exactly "final" yet: As Stiles mentioned, performance data will be used to adjust the times for the runoff. That includes readings for overnight battery charging, because all five of the runoff's competitors are all-electric. As a result, the adjusted results won't be available until Wednesday. (Check back here for updates.)

What's more, all nine of the cars still left standing have to go through laboratory tests at Argonne National Laboratory in Illinois next month. Those lab tests, which are run on a dynamometer instead of a race track, will verify that the winning cars really can get the equivalent of 100 miles per gallon of gasoline, or MPGe.

That's the main point of the X Prize competition: to promote the development of cars that are ultra-efficient as well as safe and salable.

Edison2 has taken one approach: Its aerodynamic Very Light Cars weigh about 800 pounds, which is half the weight of a Smart Car and a third the weight of a Mini Cooper. The spacey-looking vehicles are powered by one-cylinder motorcycle engines that burn an 85 percent ethanol fuel blend. Even with a tiny engine, the cars have no trouble getting up to 60 mph and reportedly can hit 110 mph - thanks to a lightweight body construction that nevertheless satisfies safety standards.

All the other X Prize vehicles are battery-powered. Some, like the ZAP Alias and the RaceAbout, look like pint-sized sports cars. Others, like the X-Tracer vehicles, look like beefed-up motorcycles. And the cars fielded by Li-ion, Aptera and the German TW4XP team look like visitors from another, cooler planet.

Peter Diamandis, chairman of the X Prize Foundation, told me today that this diversity is exactly what the competition is all about. "The future of energy is going to be diverse," Diamandis said. "I think oil and gasoline are not going away. We're going to be driving to make it much more efficient. And I think electric is on the rise. We're going to see a new generation of vehicles."

But will drivers buy cars that look like outer-space pods?

"About five years ago, I'm not sure how many people would have thought that the Smart Car was something that was similar to the type of cars people are buying today," Diamandis said. "So people's vision of what a car should look like could be changing. And then also ... these technologies from super-lightweight vehicles to control systems to suspension systems, and individual technologies might be picked off by an automobile manufacturer. That's what we need to get to revolutionary change from the evolutionary change we've been seeing."

Even the also-rans can contribute to the auto revolution, Diamandis said. The competition started out with 136 vehicles from 111 teams, and each round of the competition has eliminated teams with good ideas that couldn't quite make the grade. During just the past nine days of speedway finals, six cars have fallen by the wayside.

The latest to fade included Western Washington University's Viking sports car, which couldn't accomplish a double-lane-change maneuver on Monday. That pass-fail safety test was required to advance.

"This has been a grueling event because the standards are so high," Eric Leonhardt, the director of WWU's Vehicle Research Institute, told The Bellingham Herald. "Just to be able to have our students experience this is a great opportunity. This has really been a classroom on wheels, to get our students to get all this experience in a very short while."

Edison2's two-seat tandem car was eliminated due to mechanical troubles, leaving X-Tracer's two entrants as the last super-cars standing in that category.

Four other cars didn't make the grade during last week's fuel efficiency and range tests: the Amp electric vehicle, Commuter Cars' Tango, Spira's gasoline-powered car and Tata Motors' Indica Vista EVX. And there could be further eliminations during next month's verification stage at the Argonne Lab. Some of the competitors, such as Edison2, were just on the edge of meeting the 100 MPGe standard during the on-track runs. Those numbers will be averaged with next month's lab test numbers - and if a car's average doesn't come up to 100 MPGe, it could still be eliminated.

"It's not a slam dunk by any means," Diamandis said. "It's an X Prize, of course, and we try to make these on the edge of audaciousness that's achievable."

If multiple cars satisfy the 100 MPGe standard in the tandem two-seater category, their adjusted time in today's combined efficiency and performance test, which went for 100 miles, will serve as the tie-breaker. RaceAbout, Li-ion and TW4XP finished the course, while Aptera and ZAP fell short due to battery issues. The only way those last two teams could win the $2.5 million would be if none of the first three teams hit an average of 100 MPGe after next month's lab tests.

"There's still a lot to go," technical team director Steve Wesoloski said. "It's not over."

Brian Silva, Progressive Insurance's chief marketing officer, said he was most impressed by the level of commitment shown by all the teams. "It's the human interest side of this thing that gives you hope," he told me. "You know what? There are people out there who are going to make a difference in this world."

Once all the numbers are crunched from this month's on-track finals and next month's lab tests, the winners will be selected for a Sept. 16 awards ceremony. Any money that is not awarded will go back to Progressive, which is providing the $10 million purse as well as the cash for administering the competition.

Diamandis feels as if the contest has already had as much impact as the best-known X Prize to date: the $10 million Ansari X Prize for private-sector spaceflight, which was won by the team behind SpaceShipOne back in 2004.

"It's really about changing the paradigm," he said. "When we did the Ansari X Prize for spaceflight, the paradigm before was that only governments could fly into space. Afterwards, it was that you could be a private citizen and fly on a Virgin Galactic or a Space Adventures-Armadillo flight. The paradigm we're trying to change here is that, after the competition, we want people to know that you can have a beautiful, fast, affordable, safe car that also gets over 100 miles per gallon energy equivalent. You don't have to choose between safety and efficiency, or speed and efficiency, or cost and efficiency. You can have it all. That's the paradigm that we want, with our partners at Progressive Insurance, to get out there to the public."

But is that message really worth $10 million-plus to Progressive? "I'll tell you," Silva told me, "when you see the cars that are out here today, I really think that the 10 million dollars was a very effective use of the money."

Here's a list of the last super-cars standing after the final stage of X Prize on-track trials:

Mainstream Class Teams:
Mainstream Class vehicles must carry four or more passengers, have four or more wheels, and offer a 200-mile range.

• Edison2, Lynchburg, Virginia (E85, two cars)

Alternative Class Teams:
Alternative Class vehicles must carry two or more passengers and allow for a 100-mile range.

Side-by-side seating:

• Aptera Motors, Vista, California (Electric)
• Li-ion Motors at EV Innovations, Mooresville, North Carolina (Electric)
• RaceAbout Association, Helsinki, Finland (Electric)
• TW4XP, Rosenthal, Germany (Electric)
• ZAP, Santa Rosa, California (Electric)

Tandem seating:

• X-Tracer Team Switzerland, Uster, Switzerland (Electric, two cars)

More about the Automotive X Prize:

• Slideshow: Racing to beat 100 mpg
• Light cars take on heavy trips
• Cool car technologies you can't have now

Update for 11:55 p.m. ET July 28: The X Prize organizers have released the results of Tuesday's 100-mile runoff race:

"Team Li-Ion finished first by a narrow 0.179 seconds! RaceAbout placed second and TW4XP third by 11 minutes, 36.9 seconds.

"ZAP completed 48 laps and Aptera completed 18 laps. Both experienced mechanical issues that forced them off the track before completing the test.

"There were a few penalties assessed for speed violations:

· Team Li-ion received 1 penalty for driving under 45 mph
· RaceAbout received 2 penalties for exceeding 70 mph
· TW4XP had 4 penalties for being under 45 mph

"Mileage numbers are proving impressive given the stress of this real world challenge on the contenders. For those who completed the race, Team Li-Ion achieved a respectable 125 MPGe and RaceAbout achieved 100 MPGe. Though placing third, TW4XP achieved a remarkable 138.9 MPGe."

Here's what that means: If all of the cars going to next month's verification trials in Argonne come up to the 100 MPGe standard, Li-ion Motors wins the $2.5 million for the two-seat, side-by-side competition. If Li-ion is eliminated, Finland's RaceAbout wins. If both those cars are eliminated, Germany's TW4XP gets the money. If all three are eliminated, the X Prize judges will have to figure out whether ZAP or Alias would be eligible for the prize. But considering that all three of the finishing teams met or exceeded the 100 MPGe standard, it's almost a sure bet that the judges won't be facing such a scenario. In fact, it's almost a sure bet that Li-ion will be judged the winner sometime in the next two months.

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With only a couple of days of on-track testing left, four ultra-efficient cars have fallen out of the race for multimillion-dollar payoffs in the Progressive Insurance Automotive X Prize competition. That leaves 11 vehicles still in the running, including a couple of little cars that seem likely to bring home a big $5 million prize for the Virginia-based Edison2 team.

The months-long X Prize contest is aimed at promoting the development of ultra-efficient cars that are also safe and roomy enough to succeed on the open road as well as the showroom floor.

Both of Edison2's mainstream-class, four-seat Very Light Cars passed this week's efficiency and range tests at the Michigan International Speedway in Brooklyn, Mich. To make it through, the ethanol-burning hybrids had to hit the equivalent of 100 miles per gallon of gasoline (MPGe) during a 136-mile series of urban, city and highway drive tests. According to The Daily Progress in Charlottesville, Va., one car had a combined efficiency rating of 100.3 MPGe, while the other recorded 95.6 combined MPGe - not quite 100, but good enough to surpass this week's adjusted requirement of 90 MPGe. The cars also had to show in a separate range test that they could go at least 200 miles without refueling or recharging.

Because the two Very Light Cars are the only ones left in the $5 million mainstream competition, the Edison2 vehicles just have to fill in the final boxes on the checklist for victory: pass next week's safety and acceleration/braking tests, stick to a 100 MPGe performance during a final 200-mile run, and get their engines' performance verified during lab tests next month. It's not as easy as a Sunday drive, but at least real-estate developer Oliver Kuttner and his Edison2 teammates have no other competitors breathing down their necks.

Edison2 has a third Very Light Car competing in a different X Prize contest, the $2.5 million competition for two-seat tandem vehicles. Yet another $2.5 million awaits the winner of the competition for two-seat, side-by-side cars. The two-seaters must satisfy the same 100 MPGe requirement, but need only drive 100 miles without refueling or recharging. (Penalties of extra laps are assessed for rule infractions.)

One of the Edison2 team's secrets is the lightness of its cars. They weigh in at less than 800 pounds each, compared with roughly 1,800 pounds for a Smart Car. But just being lightweight isn't enough to take the prize, as demonstrated by this week's dropouts in the alternative two-seater classes:

• Amp's electric vehicle met this week's 90 MPGe fuel efficiency requirement, X Prize organizers said, but it exceeded the maximum carbon-dioxide emission limit (200 grams of CO2 per mile). The team also couldn't finish all its laps in the 100-mile range test.
• Commuter Cars' tiny Tango couldn't meet the fuel efficiency standard, exceeded the CO2 emission limit and couldn't finish the range test.
• Spira's gasoline-powered vehicle couldn't satisfy the minimum fuel-economy requirement.
• Tata Motors could not present its Indica Vista EVX for today's range test, due to a technical issue, and has withdrawn the all-electric car from the competition.

The front-runners that I listed after last month's Knockout phase are all still in the race: If anyone is going to win the $5 million prize this year, it'll be Edison2. The Li-On Motors Wave II recorded the highest fuel efficiency in the side-by-side two-seater category, and thus holds the pole position for one of the $2.5 million prizes. And Switzerland's X-Tracer Team still gets my vote over Edison2 for the other $2.5 million prize, set aside for tandem two-seaters.

There's a lot of driving to go yet: If more than one vehicle hits the 100 MPGe mark and satisfies all the other requirements for a particular prize, the money goes to whoever posts the fastest pace in a time trial to be run on Tuesday. So in the two-seater categories, at least, this competition could turn into a real race.

Here's the rundown going into next week's tests:

Mainstream Class Teams:
Mainstream Class vehicles must carry four or more passengers, have four or more wheels, and offer a 200-mile range.

• Edison2, Lynchburg, Virginia (E85, two cars)

Alternative Class Teams:
Alternative Class vehicles must carry two or more passengers and allow for a 100-mile range.

Side-by-side seating:

• Aptera Motors, Vista, California (Electric)
• Li-ion Motors at EV Innovations, Mooresville, North Carolina (Electric)
• RaceAbout Association, Helsinki, Finland (Electric)
• TW4XP, Rosenthal, Germany (Electric)
• Western Washington University, Bellingham, Washington (Gasoline)
• ZAP, Santa Rosa, California (Electric)

Tandem seating:

• Edison2, Lynchburg, Virginia (E85)
• X-Tracer Team Switzerland, Uster, Switzerland (Electric, two cars)

More about the Automotive X Prize:

• Slideshow: Racing to beat 100 mpg
• Light cars take on heavy trips
• Cool car technologies you can't have now

Stay tuned for X Prize updates next week. Join the Cosmic Log corps by signing up as my Facebook friend or hooking up on Twitter. And if you really want to be friendly, ask me about "The Case for Pluto."

Automotive innovators are proving that low-weight, high-efficiency cars can go the distance. But can they can make it in the marketplace?

If anyone thinks that lightweight cars can't cover long stretches of the road, the solar-powered XOF1 electric car should convince them how wrong they are. Back in 2008, the spacey-looking car's creator and driver, Marcelo da Luz, steered the XOF1 (which stands for "Power of One") from Buffalo, N.Y., to the Canadian Arctic, then down to California, then over to Florida, then back up to Canada and the Arctic again.

In April, the 470-pound XOF1 became the first all-solar car to travel Canada's Ice Highway between Inuvik and Tuktoyaktuk in the high Arctic, as documented in this amazing CBC News documentary. Da Luz now holds the world distance record for solar-powered automobile travel, racking up 22,436 miles (36,220 kilometers) on the XOF1.

Along the way, he's been pulled over 26 times - sometimes just because troopers wanted to take his picture, and one time because somebody told police in Palmer, Alaska, that a UFO was spotted traveling down the road. "They checked to make sure I'm not an alien," da Luz, who was born in Brazil and lives in Toronto, told me today. "Well, yes I am, but just because I'm not from the U.S."

Da Luz is visiting Seattle this weekend to talk about his solar-powered odyssey at the Shoreline Solar Project's annual Solarfest.

Why is a former flight attendant mortgaging his house and taking out loans to hit the road in a freaky flying-saucer car? It all began in 1987 when he heard about the Solar Challenge for sun-powered cars in Australia. "I thought, 'That's the future - I want to build a car and compete in that race.'" He put that thought on hold for 12 years, but eventually "the pain of not following the dream became unbearable," he said.

He said it took an estimated 50,000 hours of volunteer labor to build the car from polyurethane foam and fiberglass, cover it with 893 solar cells and get it on the road. The solar array's maximum output is about 900 watts. "With less energy than a toaster, I can charge the batteries and drive the car," da Luz said. The maximum range for night driving is 120 miles, but eventually the sun is going to have to shine. Da Luz's car has no provision for plug-in charging.

"On my worst days I drove for 4 miles ... or not at all," he said.

Now da Luz is hustling to raise the money for his biggest challenge yet. "If I find enough sponsors, I will drive the car from the Arctic to the tip of South America," he said. But as far as he's concerned, making money is not the point.

"The whole idea with the car is to promote the use of clean, renewable energy," da Luz told me. "Any electric car can be covered with solar cells. Maybe they will generate only 10, 15, 20 percent of the power needed for the car. But that's 10, 15, 20 percent less from the environment, and from your pocketbook."

Making cars lightweight is one of the leading strategies for making them more energy-efficient. At least that's the approach taken with the XOF1 solar car, as well as with the Very Light Cars being fielded in the $10 million Progressive Insurance Automotive X Prize by the Virginia-based Edison2 team. Unlike de Luz, however, the engineers and entrepreneurs behind Edison2 are counting on making money. Maybe lots of money.

David Imbaratto / Stellar Exploration for Planetary Society

One of Edison2's four-seat mainstream cars takes to the track during the Knockout phase of the Progressive Insurance Automotive X Prize. The car is a front-runner for the competition's $5 million top prize.

Edison2 has two experimental cars in the running for the contest's top prize of $5 million - in fact, they're the only cars that haven't been eliminated in the competition for four-seat mainstream vehicles. The team also has a two-seater in competition for one of the two $2.5 million prizes being offered for alternative vehicles.

To win the $5 million, at least one of Edison2's ethanol-burning cars will have to get the equivalent of 100 miles per gallon of gasoline (MPGe) in a 200-mile drive while satisfying all the safety and emission requirements for a marketable vehicle. To win the $2.5 million, the two-seater would have to get the same mileage but meet a less stringent range requirement of 100 miles. And by the way, it would have to beat out all the other competitors in its class.

During last month's X Prize Knockout round, one of the Edison2 mainstream cars actually exceeded the 100 MPGe mark, but after penalties were assessed for irregularities in the car's operation, the score was barely good enough to make the cutoff. The final round begins next week at the Michigan International Speedway in Brooklyn, Mich., and the stakes couldn't be higher.

"We feel good about it," David Brown, director of communications for the Edison2 team, told me today. "But we know it's a challenge and we're right on the edge. The truth is, we need to do it without penalties, and that's our anticipation."

Brown said he and his teammates are keeping its focus on the finals, "because that's important to us," but they can't help but think as well about what will happen after the X Prize.

"One of the lessons of the X Prize is that you're not going to get dramatic changes in fuel efficiency by modifying an existing car," he said.

Edison2's Very Light Cars show that low-mass vehicles can produce dramatic improvements in energy efficiency while still providing a safe, sure ride on the racetrack or on the highway. The Very Light Cars have a curb weight of less than 800 pounds - which is a third of the weight of a Mini Cooper, or half the weight of a Smart Car. "Moving toward lightweight cars, we feel strongly, is in this country's future," Brown said.

The way Edison2 sees it, the key to success isn't necessarily so much about the power source - whether it's ethanol, or diesel, or plug-in electric power, or good old gasoline. It's more about the aerodynamics and the materials that serve as the platform for the power source.

"We chose a path for the X Prize, and that path involved an internal combustion engine," Brown said. "But we actually feel what's significant about this car is the platform, and we're looking forward to exploring that platform with all the sources of power available to us. We believe it's the direction where we need to go."

Edison2's innovators may be heading in that direction, but they realize they can't create the car of the future all by themselves.

"We see ourselves developing collaborations with other companies to see these ideas go into production," Brown said. "There are all sorts of places where we took a fork in the road, but the other fork had a lot of promise, too. We feel as if there's a part of all this that ends with the X Prize - but there's also a part that starts with the end of the X Prize."

Is there a lightweight car in your future? Or do you need a heavier chassis to feel protected? Feel free to "weigh" in with your comments below.

Update for 9:10 p.m. ET: XOF1's Marcelo da Luz responded to some questions from one of my Facebook friends, Tony Rusi, and was kind enough to send me a copy of his replies. Here's the edited Q&A:

Tony Rusi: After all your experience with solar-electric cars, do you feel as if your design would be practical if mass-produced today?

Marcelo da Luz: Any electric vehicle could be covered in solar cells, even if the cells only generate 50 percent, 30 percent or 10 percent of charging due to weather and short winter days. That is 50 percent, 30 percent or 10 percent less on the environment and less on our pockets.

XOF1 was designed and built for efficiency, not as a practical vehicle to be driven every day. However, much of its technology and design can be transferred to a future vehicle design to accommodate a more practical application. For example, passenger and luggage.

Q: Do you have any ballpark idea of how much they would cost, if mass-produced by a big auto company that was making hundreds of thousands of them a year?

A: The popular Tata car is set to sell in India for about $2,500. The research and development effort cost them millions. My uneducated guess would be initially be $50,000 to $60,000, dropping down to $20,000 to $30,000 a few years later. I don't have experience with large-scale manufacturing to give an educated guess on the cost of producing a vehicle. XOF1 cost 50,000 man-hours, design, R&D, testing, etc... The reduction of cost would be a direct result of the volume being produced.

Q: Have you ever been approached by anyone from Tesla, Toyota or Nissan about mass-producing your vehicle?

A: No. I would welcome the opportunity to work with anyone interest to design XOF2. The next generation of XOF1.

Q: Did you feel safe in regular car traffic and on the freeway in the U.S. in your solar car?

A: I felt very safe. XOF1 is made out of Polyurethane foam (6-pound-per-cubic-feet density) covered in fiberglass, reinforced with carbon fiber. Foam has incredible absorbing properties in case of impact.

Q: You must be quite a spectacle on the road! Do the police stop you often because you are so novel? Or do they stop you because you create a traffic delay? And is the novelty factor wearing off at all with more electrics on the road all the time?

A: Yes, I have been pulled over by the police 26 times. In Palmer, Alaska, someone called 911 about an UFO on the road. In Washington, D.C., I got pulled over by the Secret Service on one day and a SWAT team the next day. It is not easy being green :-)

Q: Do you feel that an electric bike can be made into a solar-electric bike? Would you feel safer on a good dedicated bike trail versus a U.S. freeway?

A: Absolutely. Any electric vehicle including e-bikes could take advantage of charging with sunlight. In the case of an e-bike, a deployable panel might be more practical to use while the e-bike is stationary. It could also take advantage of small-scale wind generation while stationary. Any vehicle on a freeway should be able to sustain the minimum speed of the highway. Electric motorcycles are capable of 100 mph+. An e-bike with a 500-watt motor can't get over 20 mph, in which case they should only be allowed where human-powered bikes are.

Q: Could your solar car fairing be made to "tilt up" 90 degrees so that you could quickly get your vehicle between the closely spaced pylons that keep most motorized vehicles off of bike trails in the USA?

A: Yes, it could. However, there is always a snowball effect. Adding complexity to the design could translate in efficiency losses.

Q: I have heard that CIGS thin-film solar cells are getting near a dollar a watt. Do you know of anyone building a solar cars with those types of solar cells?

A: Due to the limited about of space to harvest solar energy, most solar vehicles use the most efficient solar cells they can get. I am not aware of anyone using thin film on a vehicle. However, for stationary applications it is a great way to reduce cost. Roofs and ports can be covered by cheap panels to charge electric vehicles.

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A $10 million competition for ultra-efficient vehicles is rolling on toward next month's finals after eliminating about a dozen of the cars vying for the prize.

The Progressive Insurance Automotive X Prize competition is aimed at rewarding the development of marketable automobiles capable of getting of 100 miles per gallon of gasoline, or the equivalent for other energy sources (a measure known as MPGe). Almost half of the cars that came to the Michigan International Speedway for the contest's Knockout stage, conducted at the Michigan International Speedway in Brooklyn, Mich., had to go home with wounded hopes.

At the most, 15 cars are still in the running for a share of the X Prize purse. And until the organizers announce the official lineup for the on-track finals, due to take place July 19-30, there's a chance that additional cars could yet be eliminated.

But there are clear front-runners for the $10 million, based on this week's results:

• If anyone is going to win the $5 million set aside for four-seat mainstream cars this year, it will be the Edison2 team, led by Virginia real estate developer Oliver Kuttner. The only vehicles left in that competition category are two of the models entered by Edison2. One of the team's hybrid Very Light Cars achieved 101.4 MPGe before penalties were assessed. But after accounting for those penalties (deducted due to repairs, drive cycle violations or other no-nos), its score fell to 67.3, barely above the 67 MPGe requirement for this round. Edison2 also has a tandem two-seater vying for an alternative prize.

• Li-ion Motors' all-electric Wave II registered the highest fuel efficiency among side-by-side two-seaters, with a 182.3 MPGe performance. That's a front-running performance among "alternative" cars in the Knockout stage. But winning $2.5 million in the finals could require speed as well as efficiency. If multiple cars satisfy all the requirements during the finals, including the 100 MPGe standard, then the prize goes to the car with the lowest elapsed time during an on-track trial that's designed to test efficiency as well as range. The side-by-side class has eight entrants, so this is potentially the most competitive category.

• Switzerland's X-Tracer Team had not just one, but two tandem two-seaters entered in the Knockout stage, and both of them were passed through to the finals. The X-Tracer cars (which look more like glorified motorcycles) had the highest efficiency scores in their class, at 180 and 171.6 MPGe. That makes them the front-runners for the $2.5 million in the tandem alternative category. During the Knockout stage, they were the only cars in their class to achieve better than 100 MPGe efficiency.

There are also plenty of disappointments. Among the teams eliminated over the past week and a half are American HyPower, BITW Technologies, Enginer, FVT Racing, Global-E, Illuminati Motor Works, OptaMotive, Team EVX and West Philly Hybrid X. The Cornell 100+ MPG Team, K-Way MOTUS and Liberty Motors Group withdrew even before the Knockout trials got started last week.

The Knockout outcome was particularly disappointing for the West Philly team, a high-school group that garnered more and more attention as the contest progressed; and for the Illuminati gang, whose retro-looking electric car offered the only competition for the Edison2 team in the mainstream class. The Illuminati Seven vehicle posted an impressive 119.8 MPGe score in the efficiency trials.

"We're out," Illuminati announced in a Twitter tweet on Monday evening. "Despite amazing efficiency MPGe, we were knocked out when our transmission broke during the Consumer Reports 0-60 test."

West Philly's converted Ford Focus fell 3.5 points short of the required efficiency score of 67 MPGe, apparently due in part to a battery-charging snafu. Simon Hauger, the West Philadelphia High School teacher who led the team, was philosophical in his Monday-morning blog post:

"Our game plan was right on, our cars ran perfectly, and our kids amazed everyone who had the pleasure of meeting them. We proved to the world that a bunch of high school kids and their teachers can build a safe, affordable, American-made car that gets over 75 mpg (over 100 mpg on the highway). This is a real car that has a real business plan. It was built by real kids and what they have done has real significance."

That's the bottom line for the X Prize phenomenon. It's not about the $10 million. ... OK, maybe it's partly about the $10 million. But in the longer run, it's about bursts of innovation that will yield real payoffs in the years to come. I can hardly wait to see how the next burst plays out.

Learn more about the teams still standing after the Knockout round:

Mainstream Class Teams:
Mainstream Class vehicles must carry four or more passengers, have four or more wheels, and offer a 200-mile range.

• Edison2, Lynchburg, Virginia (E85, two cars)

Alternative Class Teams:
Alternative Class vehicles must carry two or more passengers and allow for a 100-mile range.

Side-by-side seating:

• amp, Blue Ash, Ohio (Electric)
• Aptera Motors, Vista, California (Electric)
• Li-ion Motors at EV Innovations, Mooresville, North Carolina (Electric)
• RaceAbout Association, Helsinki, Finland (Electric)
• Tata Motors Limited, Coventry, United Kingdom (Electric)
• TW4XP, Rosenthal, Germany (Electric)
• Western Washington University, Bellingham, Washington (Gasoline)
• ZAP, Santa Rosa, California (Electric)

Tandem seating:

• Edison2, Lynchburg, Virginia (E85)
• Spira, Banglamung, Chonburi, Thailand (Gasoline)
• Tango (Commuter Cars), Spokane, Washington (Electric)
• X-Tracer Team Switzerland, Uster, Switzerland (Electric, two cars)

Check out our slideshow of X Prize competitors from the earlier Shakedown stage of the competition. And for still more about Edison2, click through to Jason Fagone's report for Slate.

Update for 1:30 p.m. ET June 30: A new spreadsheet from the X Prize lays out what happened during the Knockout stage in further detail. Most of the eliminated cars failed to reach the minimum 67 MPGe requirement, with a smattering of cars that flunked the emissions test or the technical inspection, didn't achieve 0-to-60 acceleration or simply didn't show up in time for an on-track event.

"The Knockout was just that - a true knockout - which surprised some of the teams with its rigor," Cristin Lindsay, vice president of prize operations for the X Prize Foundation, told me.

The finals could bring similar surprises. As an example, Lindsay pointed to Illuminati's transmission failure during the acceleration trial. "I could see that type of thing happening at finals again," she said. So get ready for some even more serious chills and thrills in the weeks ahead.

On the correction front, meanwhile, TW4XP is in the side-by-side alternative class, rather than the tandem class where I initially listed it.

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As many as 10 teams have fallen by the wayside in the $10 million Progressive Insurance Automotive X Prize contest for ultra-efficient cars — and other teams are working hard to stay in.

When this week's second round of on-track testing began at the Michigan International Speedway in Brooklyn, Mich., 24 teams were in the running for the prize. The competition is aimed at encouraging the development of marketable cars capable of getting 100 miles per gallon of gasoline, or equivalent energy efficiency for other power systems. That's what's known as 100 MPGe.

During this first week of the Knockout phase, the challenge has been all about being able to hit the 67 MPGe mark, which is two-thirds of the efficiency goal. The cars also had to prove that they could go 67 miles (for two-seaters) or 134 miles (for four-seaters) without refueling. If they can do that, then they move on next week to further rounds of tests to check their emission levels and handling. Those tests are due to continue until June 30. The cars that satisfy the requirements will return to Michigan for an even more grueling round of finals next month.

The $10 million purse, put up by Progressive, will be split among the top finisher in the four-seater "mainstream" category ($5 million), plus the leading two-seater "alternative" teams in two categories (tandem and side-by-side, $2.5 million each). That's assuming that at least some of the cars attain 100 MPGe, while satisfying requirements for range, emissions and safety. A lot of teams are not going to make it. AutoblogGreen's Sebastian Blanco quoted the competition's senior director, Eric Cahill, as saying he thought 10 to 16 cars would qualify to move on to the finals.

The Knockout stage isn't even over yet, and Cahill's assessment has already come true. On Friday, before the week's standings were announced, Illuminati Motor Works team leader Kevin Smith told me "there'll be some surprises on the website." The results posted on Saturday morning weren't pretty.

Smith's team was one of the survivors, but he's not overjoyed to see fellow competitors fail. "We've got some friends on other teams," he said. "It's upsetting to see this."

Here are the teams that have been dealt setbacks so far in this round:

• American HyPower: Eliminated due to a faulty fuel sensor. In a Facebook posting, the team emphasized that their elimination was not related to their car's hydrogen-fueled engine. "Although we're no longer in the competition, we'll continue to follow it as we further develop our technology," the team said.

• BITW Technologies: The standings show that the Indiana-based BITW team's Vincitore 1000, a Chevy Metro that was modified to use a three-cylinder biodiesel engine, was eliminated this week.

• Cornell 100+ MPG: Withdrew just as the Knockout stage was getting under way, due to a problem with the electronics that monitor the car's battery power, according to Consumer Reports.

• Edison2: The Virginia-based team came to the Knockout stage with four cars. This week its side-by-side two-seater was eliminated, but the team still has two four-seaters and a tandem two-seater in the running.

• Enginer: X Prize organizers said the team's hybrid steam combustion/electric vehicle was eliminated.

• Global-E: One of its two high-efficiency prototypes, the Pulse, was eliminated before the Knockout phase began. Its G1 model didn't make the grade during this week's testing, according to the X Prize standings. That means the team is finished for this year.

• K-Way MOTUS: As I mentioned a few days ago, the Italy-based K-Way team had to withdraw from the competition due to engine troubles.

• Liberty Motors Group: Also withdrew as the Knockout phase was beginning.

• Optamotive: The side-by-side, all-electric E-Rex was eliminated, but the judges' decision was still being appealed as of Saturday.

• Team EVX: The Texas-based team's all-electric SmartCar was eliminated this week.

• West Philly Hybrid X: This high-school team was a sentimental favorite, but both of its hybrid cars were knocked out during this week's trials, X Prize spokeswoman Arron Robinson told me.

That's 12 cars eliminated this week, including the two from West Philly. Nine teams are no longer in the $10 million competition, one team is appealing the elimination, and Edison2 still has other cars in the race. Additional cars could be eliminated as the teams "move on to complete next week's acceleration, braking and avoidance maneuver tests conducted by Consumer Reports' staff," Liza Barth wrote Friday on Consumer Reports' blog.

On the plus side, Western Washington University's team reportedly aced the range test on Friday and will move on to the next round. ZAP Alias said its celebrity driver, Al Unser Jr., "congratulated the team" on Friday's performance. Canada-based FVT Racing said its hybrid electric/gasoline fuel-vapor vehicle passed the range test "with flying colours."

Based on the reports so far, Kevin Smith and his Illuminati team were among the week's big winners. Their swoopy-looking Seven vehicle reportedly averaged 119.8 MPGe in its efficiency tests. AutoblogGreen's Blanco said the Seven's batteries needed some conditioning to achieve the required range - and when I asked about that, Smith acknowledged that working with the new batteries was a challenge.

"It's still posing some challenges, but we're getting there," he said.

The Knockout tests aren't finished yet. Next week, the survivors will have to prove they can handle the road safely and operate within emission standards. (The all-electric Seven should have no problem with that latter issue.) And then there are the finals next month ... and the lab tests in August ... and the awards ceremony in September. The end of the road, and the definitive demonstration that 100-mile-a-gallon efficiency is technically possible as well as marketable, is still a couple of months away for the X Prize competitors. But as Smith said, they're getting there.

Update for 9:30 p.m. ET June 28: There's more bad news from Monday's acceleration tests. Consumer Reports' Jeff Bartlett says via Twitter that the German-made, battery-electric TW4XP two-seater tried to pass its acceleration test and "did not make it." Bartlett also said Illuminati's Seven didn't make the grade: "Team Illuminati did not pass the accel test. Painful to see. Team has much to be proud of."

If Illuminati is out of the running, then the $5 million prize for the most efficient four-seat mainstream car would be Edison2's to lose. The only mainstream vehicles still in the competition are the two Very Light Cars fielded by Edison2. The same team has a two-seater in the running for an alternative-category prize. Edison2 reported that it exceeded the required 67 MPGe standard and hit 100 MPGe during the Knockout efficiency tests.

Over the weekend, I spoke with Eric Cahill, the competition's senior director, and he told me that the 67 MPGe requirement "has been the biggest hurdle" during the Knockout stage. But it sounds as if the zero-to-60 test is a killer as well. Cahill was well aware that the challenge for four-passenger vehicles is tougher than it is for two-passenger vehicles.

"We are very optimistic that we are going to have winners, most certainly in the alternative [category]," he told me. "With the mainstream [category], we're optimistic - but it's going to be a bit narrower."

Update for 12:30 p.m. ET June 29: In today's blog post, Consumer Reports' Jeff Bartlett indicates that TW4XP was at last able to pass the acceleration test. Illuminati appears to be out of the competition, along with the team fielding the Amp Electric Sky sports car. But Bartlett points out that appeals are still being heard, and so the word on some of these eliminations is not yet definitive. Stay tuned for the semifinal answers. (The finals are scheduled next month.)

Check out our wicked-cool slideshow featuring X Prize cars. Join the Cosmic Log corps by signing up as my Facebook friend or hooking up on Twitter. And if you really want to be friendly, ask me about "The Case for Pluto."

The organizers of a $10 million contest for super-efficient cars are bringing two dozen teams back to a Michigan racetrack this week for the second round of trials. And this time, they're keeping score. You can keep track of the scores yourself during the Knockout round of the Progressive Insurance Automotive X Prize.

This won't be like the typical auto race, where the first one across the finish line is the winner, no matter how much fuel is burned. These cars also have to satisfy standards for fuel efficiency, range, emissions and marketability. The key requirement is that the cars get 100 miles per gallon of gas or its equivalent (MPGe). They can run on gasoline, or biofuel, or all-electric power - and the organizers have set up a formula for calculating how much electricity is equivalent to a gallon of gas. The setup is laid out in the X Prize Foundation's contest guidelines.

Most of the cars that have come to the Michigan International Speedway in Brooklyn, Mich., survived the initial Shakedown tests that were conducted at the same track in April and May. Two European teams missed out on the Shakedown because of the air-traffic jam created by the Icelandic ash cloud. Seven other teams couldn't satisfy all the Shakedown requirements last month but were kept in the competition. Those teams were given makeup exams last week, and this week they'll find out if they can move on to the Knockout stage.

The competition is broken up into two classes of vehicles, "mainstream" four-seaters and "alternative" two-seaters, with Progressive's $10 million purse shared equally between those classes. During the Knockout stage's on-track tests, the mainstream X Prize cars will have to prove they can hit 67 MPGe, two-thirds of the ultimate goal. They'll also have to go for 134 miles without refueling - again, two-thirds of the ultimate goal of a 200-mile range. The two-seaters have the same mileage standard to meet, and they'll have to go 67 miles without refueling. Eventually the alternative cars will have to demonstrate a range of, you guessed it, 100 miles.

The first round of on-track tests didn't result in any official rankings of the contestants, but this time around, tallies will be kept for fuel efficiency, speed and the other factors that will be weighed to decide the winner. The X Prize Foundation has created a "Competition Tracker" that will put many of those metrics online as soon as they're available. There's also a leader board and team-by-team breakdowns. This YouTube video previews all the features coming to the Automotive X Prize website.

Who are the favorites?
All of the cars that meet the minimum requirements can go on to the final round of on-track tests, but the scores should reveal which teams are the favorites and which are the dark horses. So who are the favorites? That depends on what your definition of the word "favorite" is.

The ZAP Alias has risen to the top as the most stylish of the X Prize entrants, based on an unscientific online poll being conducted as part of the "Fan Favorite Sweepstakes." This contest is designed to reward the fans rather than the automotive teams: The more often you vote, the greater your chances of winning a drawing that offers $3,000 and an X Prize team jacket as the grand prize. Future stages of the contest will focus on the most innovative, most practical and most desirable cars.

The Alias has the added attraction of being driven by Al Unser Jr., who has two Indy 500 wins under his belt and belongs to a legendary race-driving family. He told The Associated Press that the X Prize could help ultra-efficient cars become mainstream in his generation. "It's not about speed, it's about humanity, and that's why I'm involved," he said.

Another favorite would have to be the Edison2 team, backed by Virginia real-estate developer Oliver Kuttner. All four of Edison2's Very Light Car entrants qualified for the Knockout stage, including two-seat as well as four-seat versions. Last month, just before accepting an "Innovator of the Year" award in Lynchburg, Kuttner said that his team hit the 83 MPGe mark, and that 100 MPGe could be achieved once there rough spots in the car's design were smoothed out.

"It will take some doing," The News & Advance quoted Kuttner as saying. He's thinking about selling some of his property so he can devote more attention to the automotive project.

The West Philly Hybrid X team would have to be among the sentimental favorites as well. About two dozen students from West Philadelphia High School transformed a Ford Focus and a two-seat EVX GT kit car into a pair of hybrid electric vehicles that both made it through the initial Shakedown stage of the competition. Money raised for the project so far: $400,000.

"We're going to produce a car that gets 100 MPG and is safe and affordable on a budget that is ridiculously small compared with any of the car manufacturers," Simon Hauger, the math and science teacher who created the team years ago as an after-school project, told The Christian Science Monitor.

California-based Aptera would have to be counted as a favorite, if only because the company is already showing off cars that are far more efficient than 100 MPG. It's counting on an X Prize win (as well as a federal loan) to boost its fortunes, with production tentatively slated for next year. During the Shakedown trials, however, the Aptera 2e appeared to experience handling problems - and that led some to question how the car would rate in the final standings.

The cars that survive this month's Knockout stage will go on to the on-track finals next month in Michigan, and the top finishers will be subjected to a final round of lab tests in August. We'll know which super-efficient cars have finished in the money in time for the X Prize awards gala in September.

Here's a full rundown of the X Prize field going into the Knockout stage:

Mainstream Class Teams:
Mainstream Class vehicles must carry four or more passengers, have four or more wheels, and offer a 200-mile range.

Passed:
• American HyPower, Centennial, Colorado (Gasoline, Hydrogen)
• BITW Technologies, Palmyra, Indiana (Biodiesel)
• Edison2, Lynchburg, Virginia (E85)
• Liberty Motors Group, Botkins, Ohio (Gasoline)
• West Philly Hybrid X, Philadelphia, Pennsylvania (Gasoline)

Given conditional pass in May:
• Cornell 100+ MPG Team, Ithaca, N.Y. (Biodiesel). Listed as "eliminated" on X Prize website.
• Illuminati Motor Works, Virden, Illinois (Electric)

Given probationary pass in May:
• Enginer, Troy, Michigan (Gasoline + Steam)
• Global-E, Mandeville, Louisiana (Gasoline & Electric)

Alternative Class Teams:
Alternative Class vehicles must carry two or more passengers and allow for a 100-mile range.

Side-by-side seating:

Passed:
• amp, Blue Ash, Ohio (Electric)
• Aptera Motors, Vista, California (Electric)
• Edison2, Lynchburg, Virginia (E85)
• OptaMotive, San Jose, California (Electric)
• RaceAbout Association, Helsinki, Finland (Electric)
• Tata Motors Limited, Coventry, United Kingdom (Electric)
• Team EVX, Dallas, Texas (Electric)
• West Philly Hybrid X (EVX), Philadelphia, Pennsylvania (Biodiesel)
• ZAP, Santa Rosa, California (Electric)

Given conditional pass in May:
• Li-ion Motors at EV Innovations, Mooresville, North Carolina (Electric)

Given probationary pass in May:
• Western Washington University, Bellingham, Washington (Gasoline)

Tandem seating:

Passed:
• Edison2, Lynchburg, Virginia (E85)
• Spira, Banglamung, Chonburi, Thailand (Gasoline)
• Tango (Commuter Cars), Spokane, Washington (Electric)
• X-Tracer Team Switzerland, Uster, Switzerland (Electric)

Given conditional pass in May:
• FVT Racing, Maple Ridge, British Columbia, Canada (Gasoline)

Shakedown tests in June, due to ash-related travel delays:
• K-Way MOTUS, Turin, Italy (Gasoline)
• TW4XP, Rosenthal, Germany (Electric)

Check out our slideshow of X Prize competitors from the Shakedown stage of the competition. We'll be passing along updates throughout the course of the Knockdown stage, which is due to run as late as June 30.

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