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Mercedes-Benz engines with 48-volt systems coming in 2017

As part of a big green push announced yesterday, Mercedes-Benz is jumping into the world of 48-volt power. The company will launch a new family of efficient gasoline engines next year and will begin rolling out 48-volt systems with it, likely in its more expensive cars first. Mercedes will use the 48-volt systems to power mild-hybrid functions like energy recuperation (commonly called brake regeneration), engine stop-start, electric boost, and even moving a car from a stop on electric power alone. These features will be enabled through either an integrated starter-generator (Mercedes abbreviates it ISG) or a belt-driven generator (RSG). (RSG is from the German word for belt-driven generator, Riemenstartergeneratoren. That's your language lesson for the day.) Mercedes didn't offer many other details on the new family of engines. There are 48-volt systems already in production; Audi's three-compressor SQ7 engine uses an electric supercharger run by a 48-volt system, and there's a new SQ5 diesel on the horizon that will use a similar setup with the medium-voltage system. Electric superchargers require a lot of juice, which can be fed by either a supercapacitor or batteries in a 48-volt system. Why 48-volt Matters: Current hybrid and battery-electric vehicles make use of very high voltages in their batteries, motors, and the wiring that connects them, usually around 200 to 600 volts. The high voltage gives them enough power to move a big vehicle, but it also creates safety issues. The way to mitigate those safety issues is with added equipment, and that increases both cost and weight. You can see where this is going. By switching to a 48-volt system, the high-voltage issues go away and the electrical architecture benefits from four times the voltage of a normal vehicle system and uses the same current, providing four times the power. The electrical architecture will cost more than a 12-volt system but less than the complex and more dangerous systems in current electrified vehicles. The added cost makes sense now because automakers are running out of ways to wisely spend money for efficiency gains. Cars can retain a cheaper 12-volt battery for lower-power accessories and run the high-draw systems on the 48-volt circuit. The industry is moving toward 48-volt power, with the SAE working on a standard for the systems and Delphi claiming a 10-percent increase in fuel economy for cars that make the switch.

Mercedes forced to lower MPG ratings on two C300 models *UPDATE

*UPDATE: Donna Boland, manager of corporate communications at Mercedes Benz USA, told AutoblogGreen that the sticker change only applied to around 500 C-Class vehicles on dealer lots, since a new C-Class came out in late August. "About 500 are left in the United States, and we've relabeled them," she said. First Hyundai, then Ford and now Mercedes-Benz. The list of companies that have had to change their vehicles' official EPA fuel economy ratings has just grown by one with the announcement that the 2013 and 2014 C300 4-Matic FFV and PZEV versions need to have their EPA labels adjusted. The changes aren't massive, at most one mile per gallon. The changes aren't massive, at most one mile per gallon, but they are lower than before. The FFV version goes from 20 to 19 mpg in the city while the PZEV drops one mpg across the board from 23/20/29 combined/city/highway) to 22/19/28. The FFV's combined (22) and highway (27) ratings stay the same. Other Mercedes vehicles that were spot checked turned out to have accurate labels. The problem, which is reminiscent of the issues that Ford had with the Total Road Load Horsepower, was that "Mercedes underestimated the impact of aerodynamic drag and tire rolling resistance known as 'road-load,'" the EPA said in a statement you can read below. We have asked Mercedes for more information on the issue but have not yet heard back. We're not sure how many vehicles the EPA is retesting (or asking to be retested), but the agency says that the C300 models were evaluated again by Mercedes "with EPA oversight" and the EPA did its own tests at the National Vehicle and Fuel Emissions Laboratory in Ann Arbor, MI. Christopher Grundler, the director of EPA's Office of Transportation and Air Quality, said that the EPA knows that the changes are minimal, but that, "it is important that our oversight system is producing the correct results because even one MPG matters to consumers." In case you need a primer in the recent history of companies adjusting their EPA numbers, check out this and this. Based on today's news, we won't be surprised to hear more changes are coming. EPA Requires Mercedes-Benz to Correct Fuel Economy Labels for Two C300 4-Matic Vehicles WASHINGTON - The U.S. Environmental Protection Agency (EPA) is revising estimates for two 2013/2014 Mercedes C300 4-matic vehicles, the FFV and PZEV, to ensure consumers are given accurate fuel economy values.

2014 Mercedes-Benz B-Class ED has 87-mile range, 84 MPGe

Well, that extra weight had to be felt somewhere. With Mercedes-Benz getting ready to start US sales of its B-Class Electric drive this summer, the big question was how well its range would stack up against other electric vehicles sold in the States. Turns out, the Benz is a bit of a juice hog. Let's say up front that the 87-mile single-charge range of the Mercedes-Benz actually stacks up nicely against its competition, since that distance puts the new model right in line with the Nissan Leaf and BMW i3 (we'll ignore the Tesla Model S for a second, here). You can find the numbers at the US Department of Energy's FuelEconomy website. As far as miles per gallon equivalent ratings, though, the Benz's steel frame makes it come up short, as it's about 1,300 pounds heavier than the carbon-fiber-body i3 and about 600 pounds heavier than the Leaf. The B-Class EV has a bigger battery than the i3 or the Leaf (36 kWh compared to 22 kWh for the i3 and 24 kWh for the Leaf) and that's one reason the car gets an 84 MPGe rating, which is about 26 percent less than the Leaf's and 32 percent less than the i3's. But at least the local utility companies will be happy. Mercedes-Benz priced the 177-horsepower B-Class ED in April at $41,450, or $100 more than the i3. Check out Autoblog's First Drive impressions here.