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The Steinbrenner Institute also found that 1.5 tons of carbon dioxide annually would be saved by the average driver if they filled tires to placard.
Using the 1995 US Department of Energy estimate, this is the equivalent of 31 billion lbs. of CO2 added to the atmosphere each year or 15.6 million tons of pollution.
3 trees are needed to offset 1.5 tons of CO2 or 46.8 million trees. This is equal to 52.6 thousand acres of trees needed to offset the unnecessary pollution from low tire pressure.

Saving the Environment