New York City's taxi cabs will go green within five years under a plan that could serve as a model for other large cities, Mayor Michael Bloomberg recently announced, Reuters reports. He said 1,000 hybrid taxis–powered by gasoline and electricity–would be introduced by October 2008, and that hybrids would gradually replace the rest of the city's 13,000 taxi cabs by 2012. New York already has 375 hybrid taxis on the road, more than any other U.S. city, Bloomberg says. Hybrid vehicles are powered by a combination of gasoline and electricity, and they emit less exhaust and have better gas mileage than other vehicles. The plan, which is based on new mileage and emission standards for cabs, will reduce the carbon emissions of New York City's fleet by 50 percent during the next decade, according to Bloomberg. While hybrid cars are generally more expensive, Bloomberg says the plan would save cab drivers more than $10,000 per year in gasoline and other expenses.