Mercedes-Benz unveiled two versions of its production-engineered "near-series" BlueZERO concept in Detroit. The five-passenger eco-runner uses modular architecture that incorporates the "sandwich floor" design initially used on M-B's first A-Class and later B-Class models. The BlueZERO that seems closest to hitting the streets is the E-Cell, a battery-electric variant capable of traveling up to 124 miles on a single charge of its lithium-ion batteries. Displayed in cutaway form, the BlueZero F-Cell uses a hydrogen fuel cell to generate power for its electric motor and has a range of over 248 miles. Missing in action was the BlueZero E-Cell Plus, a plug-in hybrid with a range-extending 1.0-liter turbocharged three-cylinder gasoline engine capable of running 62 miles in EV mode and up to 372 miles overall. Mercedes says it will start limited production of fuel-cell vehicles later this year and battery-electric drive cars commencing in 2010.