WASHINGTON – Ford Motor Co. will unveil the 2009 versions of the Escape and its corporate twin, the 2009 Mercury Mariner, at the Washington Auto Show, which opens to the public January 23– 27. Ford’s 2009 Escape gas-electric hybrid will show improvements in power and performance, according to the Associated Press.

The SUV is one of several hybrid developments at the show. Both Ford and Toyota Motor Corp. are displaying prototype plug-in hybrids while General Motors Corp. will announce that new orders from three metropolitan transit agencies would more than double its hybrid bus fleet.

Ford said overall fuel efficiency for the gasoline versions of the 2009 Escape and Mariner would increase by 1 mpg compared with the 2008 versions, which get between 18 mpg in the city and 26 mpg on the highway depending on the engine configuration. The fuel economy on the 2009 hybrid versions of the Escape and Mariner are not expected to change by any substantial amount.

Both the gasoline and hybrid versions of the Escape and Mariner will have a new 2.5L engine that will boost power 11 percent to 170 horsepower. The gasoline versions will also offer an optional 230-hp, 3.0L V-6 engine with similar gains in fuel economy. The 2009 versions of both models will go on sale this summer.

General Motors said its fleet of nearly 1,000 GM-Allison hybrid-powered buses would more than double thanks to large orders by transit agencies in Washington, D.C., Philadelphia, and Minneapolis-St. Paul.

Beyond conventional hybrids, several car makers are testing plug-in hybrids that could allow owners to plug the vehicle’s battery into a standard wall outlet to recharge it. The vehicles typically feature batteries that power an electric motor with an internal combustion engine that is used when the batteries run low.

General Motors has said production could begin as early as 2010 on a plug-in hybrid electric version of the Saturn Vue Green Line and is hoping to bring the Chevrolet Volt, a plug-in electric car, to market by the same timeframe.

Toyota said recently that it plans to test hundreds of plug-in hybrids with fleet and commercial customers by 2010. It showed journalists this past Tuesday one of the plug-in Prius prototypes, which switches from pure electric to gas engine to a blended gas electric mode, according to the Associated Press.

Chrysler LLC showed three plug-in concept cars at the North American International Auto Show in Detroit, while Ford has a partnership with Southern California Edison to develop a small fleet of plug-ins.

Whether the vehicles make it to showrooms depends on the industry’s ability to mass produce the batteries and how well they are received by fleet and commercial customers.