Back in 2004, in the tradition of the Orteig Prize won by Charles Lindbergh, the X Prize Foundation created the Ansari X Prize for Space Flight. It moved on to the contest that became known as the $10 Million Progressive Insurance Automotive X Prize. We and many others were involved early on, and have watched since. Tomorrow the winners will be announced in Washington DC, culminating a 15-month competition that started with 111 teams and is now down to 7. See the details below. We were invited to write on the Auto Prize website about the significance of the prize. You can read that first below. And tomorrow or soon thereafter, you can go to http://autoblog.xprize.org/ where you'll be able to comment on our perspective and those of others invited to post.

WATCH THE ANNOUNCEMENT CEREMONY streamed live, at 10:30AM EST/7:30AM PST, and get information about the event at http://www.progressiveautoxprize.org/­live . And watch a one-hour special, "X PRIZE Cars: Accelerating the Future", on the National Geographic Channel on Thursday, September 16 at 9:00 PM ET/PT.

THE ORIGINS OF THE PROGRESSIVE AUTO X PRIZE -- AND ITS IMPACT

This is a guest posting by Felix Kramer, Founder of the California Cars Initiative (CalCars.org)

Five years ago, when the Automotive X Prize was just an idea, gas prices were seesawing, and people were fed up with paying a billion dollars a day for foreign oil. We're still addicted to oil -- but thanks in large part to the X Prize, we can see a way out.

Back then, the famed Hypercar spinoff from Rocky Mountain Institute had previewed a future of lightweight, aerodynamic, safe autos. And everyone who'd looked at ways to reduce greenhouse gases knew the answer had to include getting our vehicles off fossil fuels. It was time for cars to take a quantum leap.

Meanwhile, promising cars like the GM EV1 and Toyota RAV4 EV were history. But the death of the electric car turned out to be just the end of one chapter. In 2004, CalCars.org showed how to convert hybrids to plug in, plastering five-foot wide signs proclaiming "100+MPG" on the sides of our Prius retrofits. And Tesla raised money to build a sexy sportscar that would beat almost anything on the road. We could see a future of optimized vehicles running on cleaner, cheaper, domestic electricity.

The Automotive X Prize launched in 2006-07 with ambitions to inspire the public and spark innovation to change the auto industry. Getting the competition right wasn't easy for its dedicated, creative staff:

• When "100 MPG" came up against vehicles powered by different fuels, experts developed "MPGe" for apples-to-apples comparisons of electricity with petroleum and renewable biofuels.
• Faced with public expectations for glitzy track races, planners who knew drivers most need a fuel-miser for 25-mile-a-day commutes worked out new tests. They enlisted the U.S. Department of Energy's National Labs to validate the performance of innovative solutions.
• With hopes that some great idea would emerge from a quirky corner, they split the Prize into mainstream and alternative paths.
• Recognizing that improving the efficiency of millions of cars already on the road could make a huge impact, they opened the competition up to retrofits and conversions.
• And, knowing that imaginative, unique solutions also had to find their ways to millions of drivers, they made competitors show their designs could be safe, affordably mass-produced, and sold for a profit.

As we reach the end of this historic competition, we all wonder who will win. But it's never been more true that "the journey is the reward." Competitors that didn't make it all the way have gained significant visibility, investments, and partnerships. Some may become successful manufacturers. Others will see their teams, intellectual property, and visions acquired by larger companies. Many will celebrate their victories.

Of course, the Prize's impact extends far beyond the competition. X Prize raising the MPG bar certainly encouraged Congress to increase fuel efficiency standards. As we debate what new car stickers should say about efficiency and emissions, a new coalition is urging a goal of 60 MPG by 2025. The DOE has funded development of an advanced U.S. battery industry and lent carmakers billions to retool for green automotive jobs. States and companies have added their incentive programs to the federal $7,500 tax credits for new plug-in cars. Engineering students have been inspired to find jobs in a reviving auto industry. High schoolers have seen how cars can be cool and clean.

And automakers? They've been watching closely and making industry-changing decisions. In 2006, I became the world's first consumer-owner of a plug-in hybrid. Now, before the end of this X Prize year, my family hopes to replace that PHEV conversion with a Chevy Volt that we can drive everywhere. And we'll trade our reliable Toyota Camry Hybrid for a Nissan LEAF's daily drives with no gasoline. The cars are coming: the U.S. is on track for a million mass-produced plug-in cars by 2015!

What's next? How about a follow-on prize? As the high-MPG cars arrive, it's clear it will take decades before they'll make up a large enough fraction of our country's 250 million vehicles to have much impact on fossil fuel use. Visionaries like Andy Grove are urging us to retrofit tens of millions of pickup trucks, SUVs, vans, and buses. Like the Home Star building retrofits we're now accelerating, national gas- guzzler conversions could create green jobs in communities everywhere. So CalCars hopes for a Drive Star competition -- from X Prize, DOE, or another sponsor -- to spark "The Big Fix," creating a global industry to upgrade many of the world's 900 million vehicles.

X Prize began with the Ansari X Prize for space flight. As the X Prize Foundation broadens, with prizes in genomics, lunar exploration, and ocean oil cleanup, it's never been clearer that humanity and our planet face immense challenges. We used to say "the sky's the limit." Now that we recognize we need to save that one sky ASAP, we look to future competitions for inspiration, ideas, and a global rescue.