Building on its XJ Limo-Green project of 2009, Jaguar has unveiled today an updated XJ plug-in hybrid prototype at the 2012 Goodwood Festival of Speed.

Capable of accelerating from 0-60 mph in under 6.5 seconds and cruising to a top speed of 150 mph, the XJ prototype, dubbed the XJ_e, delivers performance that’s on par with some sports car models also on show at Goodwood, but with better fuel economy than a compact.

Part funded by the British government’s Technology Strategy Board through the REEVolution project, which is aimed at not only developing green vehicles but the infrastructure to manufacture them as well, the XJ_e shares much of its technology with the previous Range_e prototype from sister company Land Rover and hints at what’s to come from the automakers in the near future.

Starting with the lightweight aluminum chassis of the XJ flagship sedan, Jaguar engineers installed a plug-in hybrid drivetrain pairing a turbocharged and direct-injected 2.0-liter four-cylinder engine with an electric motor. This is the same engine found in the Range Rover Evoque and in the XJ_e is matched to an eight-speed automatic transmission.

The design allows the XJ_e to run on gasoline, electricity, or a combination of the two, optimized by the car’s intelligent energy management system which selects the most efficient mode.

The electric motor is rated at 92 horsepower and is powered by a 12.8kWh lithium-ion battery capable of delivering an electric only range of 25 miles. Working in combination with the four-cylinder engine, peak output rises to 330 horsepower while fuel economy rates in at an impressive 73 mpg combined. This translates to a complete driving range of around 680 miles on a full charge of the batteries and a single tank of gas.

Speaking at the unveiling of the prototype, Jaguar engineering boss Bob Joyce said, “The XJ_e investigates how a 5.0-liter V-8 engine could be replaced by an advanced 2.0-liter hybrid powertrain to deliver similar performance and refinement, but with CO2 emissions of less than 75g/km.  While the XJ_e is an experimental project, it highlights that Jaguar Land Rover customers can expect some exciting low-carbon products in the future.”

Note, while the XJ_e isn’t in production just yet, a ‘greener’ XJ is being launched for the 2013 model year. The 2013 Jaguar XJ picks up a supercharged 3.0-liter V-6 as its base engine instead of the previous model year’s 5.0-liter V-8 base option. EPA figures for the new engine are yet to be released but European tests have shown that the blown V-6 is around 33 percent more efficient despite only losing 50 horsepower on the V-8.


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