BMW Concept 7 Series ActiveHybrid
Unveiled at the 2008 Paris Auto Show, the BMW Concept 7 Series ActiveHybrid is the most recent addition to the German brand’s line of eco-conscious vehicles. Part of BMW’s EfficientDynamics development program, the 7 Series ActiveHybrid’s 20 mpg fuel economy is on nearly par with the Lexus LS 600h L. Underneath the hood is a 4.4-liter twin-turbo V-8 engine, which works in tandem with a lithium-ion battery-powered electric motor to produce more than 400 hp. Unlike the Lexus hybrid, however, the electric motor is not able to move the car on its own, and BMW has not announced any plans to make the 7 Series ActiveHybrid into a full production model. BMW, www.bmwusa.com

Mercedes-Benz S400 BlueHybrid
Not to be outdone by Lexus, Mercedes-Benz’ parent company, DaimlerChrysler, entered a joint engineering program with BMW to develop a new line of hybrid vehicles. The S400 BlueHybrid is the first of many gas-electric models scheduled for the U.S. market. Based on the current generation S-Class, the new hybrid will use lithium-ion technology and a 3.5-liter V-6 engine to achieve a commendable 30 mpg. Mercedes-Benz claims that the luxury sedan will reach 60 mph in about seven seconds and expects to have as many as seven hybrid models available by 2015. No official price is set at the moment, but the S400 BlueHybrid is estimated to cost around $100,000 when it arrives Stateside at the end of 2009. Mercedes-Benz, www.mbusa.com