Mazda announced today its range of vehicles sold worldwide will use an average of 30 percent less fuel by 2015 thanks to lighter weight and more advanced gasoline engines that use an Idle Stop System that shuts down engines when vehicles are stopped. Also, the company will introduce a new rotary powerplant (traditionally a heavy gas user) as well as a new diesel engine.

The undertaking is no doubt spurred by the recent CAFE standards for North America, as well as the high cost of gas worldwide driving customers to purchasing more fuel-efficient vehicles.

The Japanese automaker is committed to developing new platforms that will reduced vehicle weight by at least 220lbs from 2011 forward. The engine shutdown / restart system will launch next year in one vehicle sold in Europe and Japan. The system will quickly and quietly fire up the engine when it’s time to proceed, with Mazda claiming an improvement of between 7 and 8 percent.

An E85-capable FlexFuel gas engine will also launch in 2009, while by 2011, all gasoline engines, including the rotary, will feature Mazda’s DISI direct injection set-up good for a 15 to 20 percent power boost and 20 percent power hike. The rotary-powered, hydrogen-burning Premacy Hybrid is also likely to contribute to the average fuel use decrease.

Other “green” initiatives Mazda will introduce include producing carbon-neutral bioplastics for the interiors and fascias of its vehicles by 2013.

The factories will also get cleaner, thanks to a Three Layer Wet Paint system coming next year, reducing VOC emissions by 57 percent and CO2 by 15. The process produces about 25 percent less CO2 emissions than usual water-based paint procedures.