The fleet of new cars and trucks sold in the United States in 2025 may be required to average 26 kilometres per litre, far surpassing the fuel efficiency of current high-mileage stars like the Toyota Prius and Honda Civic hybrids.


Workers give the final check on a newly assembled 2010 Prius hybrid at Toyota Tsutsumi Plant in Toyota, central Japan. Proposed fuel efficiency standards in the U.S. exceed the current Prius gas mileage rating. ((Shizuo Kambayashi/Associated Press))

The government on Friday was presenting potential ranges of fuel efficiency standards for new cars and trucks being built later this decade.

The Transportation Department and Environmental Protection Agency planned to say the fleet of new vehicles may need to meet a standard set somewhere from 20 kpl to 26 kpl, people familiar with the discussions said. They spoke on condition of anonymity because they were not authorized to speak before the official announcement.

They said the mileage gains were the  equivalent of an annual decrease in carbon dioxide emissions per mile of three per cent to six per cent.

The new standards, while several years away, are closely watched by automakers who plan vehicle lineups years in advance and environmental groups trying to curb oil dependence and reduce greenhouse gas emissions.

U.S. President Barack Obama has pushed for tougher fuel efficiency standards and the rules could take on added significance if Congress is unable to pass energy legislation capping greenhouse gases blamed for global warming.

Fuel efficiency to improve 40% by 2016

After little progress during the past three decades, rules adopted earlier this year will lift the new vehicle fleet average to 15 kpl by 2016, an increase of more than 40 per cent over current standards. The administration is beginning work on mileage standards for the 2017-2025 model years. The government intends to issue a proposal in September 2011 and a final rule by late July 2012.


Nissan will begin selling the Leaf electric car later this year, opening a new wave of electric vehicle options. ((Itsuo Inouye/Associated Press))

Environmentalists have sought requirements of at least 25 kilometres per litre by 2025, arguing that more gas-electric hybrids, electric vehicles and cars and trucks with improved internal combustion engines and reduced weight could dramatically alter the fleet.

Automakers have cautioned that pushing gas mileage standards up that quickly could force them to raise prices beyond the reach for many consumers.

If met, the targets would bring topflight fuel efficiency to a larger number of vehicles in 15 years. For example, a new Toyota Prius gets 21 kpl combined and a Honda Civic hybrid garners 18 kpl in city-highway driving — figures that would become more commonplace across the fleet.

Later this year, several automakers will begin releasing plug-in electric hybrids and electric cars. General Motors is releasing the electric rechargeable Chevrolet Volt and Nissan Motor Co. begins selling the Nissan Leaf electric car, opening a new wave of electric vehicle options.

The government's so-called "notice of intent" document gives automakers, environmental groups and states an overview of the possible standards, describing the technologies that would be needed to achieve those goals. It seeks feedback from the public and the two federal agencies plan to issue a second "notice of intent" by Nov. 30 with an updated analysis of potential targets for the 2017-2025 period.

The government is also expected to soon release a proposal for first-ever fuel efficiency and emissions standards for medium-duty and heavy-duty trucks beginning with the 2014 model year.