Updated: The Automotive X Prize challenge has officially started with the announcement today of a title sponsor at the New York Auto Show. Progressive Casualty Insurance will front the $10 million cash prize for the first team to successfully build and race a commercially viable 100mpg vehicle. The challenge will run over the next two years and include a cross-country challenge in the U.S.

Original: We’ve been reporting about the new Automotive X Prize challenge for close to a year and now the official start of the race to build a commercially viable 100mpg vehicle is less than a week away. At next week’s New York Auto Show organizers will announce a new title sponsor and signal the official beginning of the competition.

A select number of teams will display their vehicles at the upcoming show, including Aptera who will be presenting its Typ-1 300mpg plug-in hybrid (pictured).

The goal of the latest Automotive X Prize challenge is to design, build and bring to market a 100mpg vehicle that people would want to buy and that meets market needs for price, size, capability, safety and performance. To date, more than 60 teams from nine countries have signed a ‘Letter of Intent’ to compete for a share of the multimillion dollar prize. The competition will also include a cross-country challenge in the U.S. over the next two years.

The X Prize Foundation first made headlines in 2004, when Mojave Aerospace Ventures (MAV), led by aircraft designer Burt Rutan and Microsoft Co-founder Paul Allen, built and flew the world's first private aircraft into orbit. For its efforts, MAV won a cash prize of $10 million.

The following is a list of the first 31 teams to sign up for the latest challenge:

• Aptera Motors – California, USA

• Commuter Cars Corp. – Washington, USA

• Cornell University – New York, USA

• DEHyds – Washington, USA

• Delta Motorsport – Northants, UK

• Desert Fuel – Arizona, USA

• Disruptech – California, USA

• Dragonfly Technology LTD – Northhampton, UK

• Fuel Vapor Technologies – British Columbia, Canada

• GreenIt! – Oregon, USA

• Herf Duo – Berlin, Germany

• HyKinesys – California, USA

• Kinetic Vehicles – Oregon, USA

• Kuttner Doran Inventions – Virginia, USA

• Loremo AG – Munich, Germany

• Maine Automotive X – Maine, USA

• MDI, Inc. & Zero Pollution Motors LLC – New York, USA

• Michigan Vision – Michigan, USA

• MotoTron Corporation – Wisconsin, USA

• Phoenix Motorcars – California, USA

• Prometheus Systems, LLC – Arizona, USA

• Porteon Electric Vehicles, Inc. – Oregon, USA

• Psycho-Active – Georgia, USA

• Roane Inventions – Texas, USA

• Society for Sustainable Mobility – California, USA

• Spirit One – Alberta, Canada

• Tesla Motors – California, USA

• Valentin Technologies – Wisconsin, USA

• Velozzi – California, USA

• X Tracer – Winterthur, Switzerland

• ZAP Motors – California, USA