Similar to the drivetrain due for the forthcoming Model X SUV, this adds a second motor at the front axle, joining the single rear-mounted motor on two-wheel drive versions, and will allow the Model S to compete with four-wheel drive rivals from Audi, BMW, Jaguar and Mercedes-Benz in markets which demand the extra traction.

Dual-motor cars are available with the same choice of 60kWh and longer-range 85kWh batteries as the two-wheel drive Model S, and while European pricing has not been announced yet, these add an extra $4,000 to the list price in the United States. Both produce 376bhp, split equally between the two axles, and offer a slightly longer range than a two-wheel drive car.

The most significant upgrades are found on the P85D, which adds a 221bhp electric motor to the P85’s 470bhp rear motor, producing a combined 691bhp and propelling the car to 60mph in 3.2 seconds, a second faster than the two-wheel drive car, while the suspension has been upgraded for a sportier drive.

Tesla’s fastest version yet is priced at $14,600 over the P85 performance, and features the same smart air suspension and 21-inch wheels as the now discontinued P85+ which used to be the range figurehead. Its electric range, as with the 60D and 85D versions, is higher than the two-wheel drive equivalent.

In addition to drivetrain upgrades, the 2015 Model S adds new technology which will enable some driving functions to be automated. All cars will feature forward-looking cameras and 360-degree ultrasonic sensors, and Tesla says it will add “Autopilot” functions such as lane keeping, active cruise control the ability to manoeuvre out of a garage, through future software updates which will be downloaded over the air to the car’s dashboard.

At the time of writing, Tesla’s UK online configurator was disabled ahead of pricing updates due in the near future. Deliveries of the P85D begin in December in North America, followed by the 85D and 60D in February, and all three will launch in Europe and Asia shortly afterwards.