Mayor Bloomberg has announced a plan that will require better fuel efficiency for city's TLC-run black cars; the change is part of the broader PlaNYC initiative and follows in the tread marks of the new hybrid yellow cabs. Emissions will be halved for the fleet of 10,000 black cars, which currently release 272,000 tons of CO2 equivalents annually, making up 2% of the City's transportation related emissions. The fleet is a part of the Taxi......