GM's hybrid concept car, the Chevy Volt, is already gracing TV screens as part of the company's 'From gas friendly to gas free' campaign, but now GM have launched another eco-friendly concept vehicle, the Cadillac Provoq Fuel Cell E-flex. Aside from solar panels built into the roof, the Provoq has plenty of unique features. The car will run on a hybrid electric engine fed by a hydrogen fuel cell, which they believe will help the car achieve a range of 300 miles for every three kilograms fill of hydrogen; 0-60 in 8.5 seconds and a top speed of 100 MPH.

Rather than offer a power boost to the engine, the solar powered roof would be used to power onboard electronics such as the intelligent front grille, which will automatically open when the engine needs cooling but close at higher speeds to reduce drag and therefore improve fuel economy.

Despite the fact that the Volt and the Provoq won't be hitting the roads for several years, it is eco-friendly concepts such as these that helped GM this month win the inaugural Earth Angel Award at the International Car of the Year Awards (ICOTY).

All automakers were invited to enter the inaugural competition by answering a six-part questionnaire related to environmental initiatives. Respondents included BMW, Mercedes-Benz, Ford Motor Company, GM, Honda, Hyundai, Subaru and Toyota. Based on a review of their answers by the ICOTY Award's jury, General Motors Corporation was awarded as the most environmentally-friendly automaker.

In 2007, General Motors reduced energy and water consumption at manufacturing facilities worldwide. The company also succeeded in cutting its CO2 emissions by more than 16 percent since 2002. Additionally, GM led the way in solar energy, unveiling the largest corporate-based solar power warehouse in September at its Service and Parts Operations facility in Fontana, California.

Factors considered in the judging process included present and future environmental initiatives sponsored or supported by the automaker; current hybrid electric, diesel and flex-fuel vehicles available to the public; and the automaker's position and mission on global warming.