Finding inexpensive ways to reduce fuel use is a burgeoning business, and U.S. carmakers have joined forces to promote a program that aims to re-train the way drivers approach their cars.

By focusing on maintenance and driving style, the EcoDriving website, launched by the Alliance of Automobile Manufacturers an the Environmental Defense Fund, promises to reduce fuel use by up to 15%.

This is not the first time the industry has gotten together to encourage smarter driving and better vehicle maintenance, however. Back in May a wesite called Drive Smarter Challenge launched as part of an initiative by the Wal-Mart foundation and the Alliance to Save Energy along with Ford, GM, Chrysler, Toyota and six other manufacturers.

A very similar push was made in the EU in January, with results in that application claiming an improvement in efficiency of up to 25%.

The basic theme behind all of these movements involve keeping tire pressures at recommended levels to ensure lower rolling resistance than under-inflated tires, using delicate application of the throttle, and minimizing excess braking. According to the Alliance of Automobile Manufacturers, if half of the drivers in the U.S. adopted the techniques, CO2 emissions could be cut by up to 100 million tons each year. That's enough power to keep 8.5 million houses running for a year.