The USA Environmental Protection Agency (EPA) and National Highway Transport Safety Administration (NHTSA) have released new draft fuel economy targets, dubbed the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule.
The agencies propose freezing the fuel economy target at 2020 model year levels for a further five years.
Under the policy enacted by the Obama administration in 2012, the target would have risen progressively from 37mpg (6.4L/100km) in the 2020 model year to 46.5mpg (5.1L/100km) in 2025 model year.
Both the targets from the Obama and Trump eras will not apply uniformly to all vehicles, instead vehicles will be assessed based on their footprint and respective category, passenger vehicle or light truck.
According to Automotive News, under the existing rules a Honda Jazz would need to need to return 62mpg (3.8L/100km) by 2025, while a Chevrolet Silverado would be compliant if it hit 35mpg (6.7L/100km).
The government agencies claim its new proposal will save up to 1000 lives per year, as the less stringent standard will allow more people to afford new and safer vehicles.
In their view, the proposed changes will increase daily fuel consumption rise by two to three per cent, but have "no noticeable impact" on smog-forming or other toxic air pollutants.
Atmospheric carbon dioxide levels are estimated to increase to 787.76 parts per million (ppm) by 2100.
On the flip side, the EPA and NHTSA estimate the new rules will save automakers US$252.6 billion ($340 billion) in extra technology costs, and somehow reduce "costs attributable to additional congestion and noise" by US$51.9 billion ($70 billion).
As part of the SAFE rule package, the federal government is also seeking to revoke California's ability to set its own greenhouse gas emissions targets for vehicles, as well as the state's zero emissions vehicles mandate.
The administration is hoping to have the new rules in place by the end of the year, with the draft proposal currently open to a 60 day comment period. California and other states which follow its standard have indicated they will take legal action, which could significantly delay matters.
The Alliance of Automobile Manufacturers and the Association of Global Automakers are supportive of the proposed changes, saying they "support continued improvements in fuel economy and flexibilities that incentivise advanced technologies while balancing priorities like affordability, safety, jobs, and the environment".
They noted "it’s time for substantive negotiations to begin", and urged "California and the federal government to find a common sense solution".
The industry groups represent manufacturers ranging from Ford, GM, Fiat Chrysler and Toyota, through to BMW, Mazda, Volkswagen, Porsche and Volvo.
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