A car, going green. (Photo by dalee.)

Last week, the EPA and the National Highway Traffic Safety Administration announced a delay in the release of the government’s new fuel-efficiency standards. The rule was supposed to come out last Wednesday; now its release date is to be determined.

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The Financial Times explains what is expected of the new standards:

If, as expected, the new rules reflect draft standards published last year, they foresee a near-doubling of US-made cars’ average fuel efficiency by 2025 from 27.5 miles per US gallon at present to 54.5mpg, under test conditions.

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Mr Obama set out the plan in July last year, following an agreement with 13 leading carmakers to support the new standards, which he described as “the single most important step we’ve ever taken as a nation to reduce our dependence on foreign oil”.

The official assessment of the environmental impact of the new regulations, published by the US National Highway Traffic Safety Administration last month, shows that the changes could cut the country’s road fuel demand by up to 1.19tn gallons over 2017-60, a reduction of 18 per cent from the level if the rules were not imposed.

When the new standards were announced, auto manufacturers came out in support of the efficiency increase.

Over the past three decades, gasoline consumption has already dropped significantly. In May, refiners sold 30 million gallons of gasoline a day — far less than even 10 years ago.

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At the same time, cars are getting cleaner. As Treehugger notes, NOAA recently demonstrated what a reduction of smog-forming emissions can do for a city.

In California’s Los Angeles Basin, levels of some vehicle-related air pollutants have decreased by about 98 percent since the 1960s, even as area residents now burn three times as much gasoline and diesel fuel. Between 2002 and 2010 alone, the concentration of air pollutants called volatile organic compounds (VOCs) dropped by half, according to a new study by NOAA scientists and colleagues, published in the Journal of Geophysical Research [on August 8].

VOCs are a key contributor to smog, explaining Los Angeles’ no-longer-always-horrible air quality.

Again, Los Angeles’ reduction in emissions comes despite increases in fuel use. If we can drop consumption while we keep making cars cleaner?

The sooner the better on those CAFE standards, gang.