2015. Variants and nomenclature The last part of the model name indicates how the vehicle is powered: Natural Gas Drive: c, e.g. B 200 c (for compressed natural gas) Diesel: d, e.g. B 250 d Electric: e, e.g. B 250 e Fuel cell f, e.g. B 200 f All-wheel drive: i.e. B 250 4MATIC BlueEFFICIENCY BlueEFFICIENCY is a term used by Mercedes-Benz for a series of measures which reduce fuel consumption and emissions. These include: Start/stop function switches off the engine temporarily when the vehicle is stationary. Alternator management for regenerative braking. Tyres optimised for rolling resistance have low energy requirements while driving and also help to reduce fuel consumption. The B 180 CDI BlueEFFICIENCY Edition was available from September 2011. B 200 Natural Gas Drive Production version includes a choice of manual and 7G-DCT dual clutch transmission, and was available from early 2013. European model was set to go on sale in February 2014. B-Class Electric Drive Initial concept versions of the B-Class Electric Drive were developed under the Mercedes-Benz BlueZERO project using batteries from Li-tec and a drivetrain from Tesla, but Mercedes switched to using a drivetrain developed by Mercedes itself soon after. The Electric Drive was previewed at the 2012 Paris Motor Show, the 2013 New York International Auto Show, and the 2013 IAA International Motor Show 2013. Production for retail customers began in April 2014 at Mercedes-Benz Rastatt factory. In May 2014, Mercedes announced the B-Class Electric Drive will be available in Germany and the UK in the first quarter of 2015. In November, Mercedes-Benz announced pricing for Germany and started accepting orders. The concept has an electric motor rated and , 36 kWh lithium-ion battery from Tesla Motors. The vehicle has a driving range of with a top speed of . The battery can be charged at any standard domestic 230 V power outlet or 400 V rapid charging terminal. Pricing in the U.S. starts at before any applicable tax credits and other government incentives. In 2015, over 1900 electric B-class were sold in the US. The United States Environmental Protection Agency (EPA), under its five-cycle testing, rated the 2014 B-Class Electric Drive with an all-electric range of . The energy consumption was rated at 40 kWh/100 miles for combined city/highway driving, corresponding to a fuel economy of 84 miles per gallon gasoline equivalent – MPGe (2.8 L/100 km; 101 mpg imp). The rating for