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                                 It is the kind of car that makes a statement when it arrives at the valet or country club parking lot
              There are already several luxury car makers that offer gasoline-electric hybrid vehicles; some offer versions that can be plugged in to help charge their batteries, such as the 2018 Karma Revero. But besides the stunning design with boutique price tag and ownership experience, what makes the Revero different? For one thing, it’s one of only two series- hybrid vehicles available that are effectively electric vehicles that also have range-extending internal combustion engines. By contrast, all other hybrid vehicles in the U.S. market, regardless of whether they can be plugged in to charge, are parallel hybrids.
Under some circumstances, certain parallel hybrids can run in pure EV mode, but parallel hybrids typically blend their electric motor’s and gasoline engine’s power for a combined output. There’s a mechanical link between the two power sources, usually within a complicated transmission or two. Not so in a series hybrid such as the Karma Revero. It is “filled” with both gasoline (only 9.5 gallons) and electricity, but it uses its gasoline solely to generate electricity, supplying juice to a battery pack and/or to power electric motors that in turn move the vehicle. The only other car on the market right now that also does this is the BMW i3 EV with its optional range-extender engine. The Karma Revero’s progenitor, now defunct Fisker Karma, was the very first production automobile in the U.S to offer this type of powertrain in 2012. We tested a prototype of that car in late 2011, and although much has changed, many of the fundamentals remain the same.
Under the Revero’s impossibly long, low hood lies a GM- sourced 2.0-liter turbocharged four-cylinder engine that produces a maximum 235 horsepower. The exhaust pipes dump out just behind the front wheels. The Revero’s battery pack runs down the centerline of the car in what would appear to be the car’s shaft tunnel. The batteries’ capacity is 21.4 kilowatt-hours, of which 18.9 kWh are usable. At the
There are three drive modes; Stealth, Sustain and Sport
rear of the car are two AC permanent magnet synchronous traction motors that provide a combined 403 horsepower for propulsion.
Charging the LithiumIon batteries through the car’s onboard 6.6-kW charger at Level 1, 120 volts at 16 amps, like a typical household outlet, will take 10 hours. At Level 2, 240 volts at 32 amps, that time drops to 3 hours and 45 minutes. Using Level 3, 480 volts at 110 amps and an off- board 40-kW DC/DC quick charging station similar to a Tesla Supercharger, reaching 80 percent of the battery’s capacity takes just 24 minutes. The Revero’s solar roof contributes an almost infinitesimal 0.2 kW to the car. With 9.5 gallons of gasoline and a fully charged battery, the EPA says the Revero will first travel 32 miles as an EV then an additional 188 on the gasoline generator for a total range of 220 miles. Karma reports slightly better EV and combined ranges during its own testing. For perspective, that BMW i3 with a range extender is rated by the EPA to have a 97-mile EV range and a total range of 180 miles. The Chevrolet Volt is rated by the EPA to have a 53-mile EV range and a total range of 420 miles.
There are three drive modes to choose from: Stealth, Sustain and Sport. The reason for being able to select modes is simple. Say you live in city center that has strict rules concerning or exorbitant taxes on running internal combustion engines. You’d use your Stealth mode in town then could switch to Sustain outside of town to maintain your batteries’ state of charge before returning to the city where you would switch back to Stealth. If you have a 32-mile commute, you could get to work in EV mode, plug in there on a Level 2 charger, then return home in EV mode, without ever using gasoline.
As with all EVs, the Karma Revero is quiet in Stealth mode. EVs seem to have overly loud wind and tire noise as they go down the road because there is no powertrain noise to mask the sound. Karma knew this and took extra sound measures to quiet the cabin. They did an excellent job with
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