Volvo XC90 T8 7-seat SUV with ‘twin engine’ technologyDecember 16, 2014
The Volvo XC90 T8 is a 7-seat SUV with ‘twin engine’ technology and emissions of just 59g/km CO2.
The first Volvo designed from the ground up for plug-in/electrification compatibility, the XC90 T8 delivers all the performance of a luxury SUV, but with emission levels that even small hybrid cars struggle to match.
By building on the new modular Scalable Product Architecture (SPA) platform and Drive-E petrol powertrain, Volvo has created a 7-seater SUV that delivers 400hp/640Nm combined with ultra-low emissions expected to be 59g/km.
The XC90 T8 can accelerate from 0 to 62mph in 5.9 seconds and has five different driving modes.
Hybrid: The default mode, suitable for everyday use; the vehicle will automatically alternate between drawing power from the 2-litre, 4-cylinder Drive-E engine and the electric motor to deliver the best overall fuel consumption.
Pure electric: In this mode, when the high-voltage battery is fully charged, it serves as the car’s sole energy source, powering the electric motor over the rear axle. The XC90 T8 has a range of up to 25 miles using just electricity, which covers the total distance most people drive in one day. And thanks to the regenerative braking system, this mode is efficient in the stop-and-go traffic of city environments. If more power is needed, the Drive-E combustion engine starts up automatically.
Power mode: This mode combines the performance of the combustion engine and the electric motor. On start-up, the SUV takes advantage of the electric motor’s superior response and instant torque curve, while the combustion engine gets up to speed. This combination offers better torque at lower revs, equivalent to that of a large displacement engine such as a V8.
AWD: This mode offers constant all-wheel drive on demand.
Save: If the battery is charged, this mode allows the driver to “freeze” the battery level and save it for later use with Pure Electric drive. If the battery is low, the driver can use the combustion engine to charge the battery to a certain level for later use with Pure Electric drive.
Many of the XC90 T8’s powertrain features have been optimised specifically for hybrid technology. Here are the main components of the system:
A specially modified version of the 4-cylinder Drive-E petrol engine is enhanced in the XC90 T8 by a supercharger and a turbocharger for a total power output of 318hp and 400Nm torque.
The 8-speed automatic gearbox has also been specially adapted for the hybrid: shift-by-wire technology allows drivers to control the transmission electrically. A larger oil pump provides the necessary lubrication during electric drive and enables quicker pressure build-up when seamlessly going from electric to combustion drive.
The crankshaft-mounted starter generator (CISG), located between the engine and the gearbox, performs three functions: it’s a powerful, 34kW starter motor that allows the car to go from pure electric drive to combination combustion drive seamlessly, so drivers can experience the car’s petrol engine and electric motor as one unit; it is also a powerful electric generator; and finally, it acts as an electric engine booster, working with the supercharger and turbocharger when extra power is needed, providing up to 150 Nm of extra torque.
The high-voltage (270–400V) battery, delivering 65kW of power is located centrally in the tunnel of the car. The battery doesn’t impact on the amount of available space inside the car, meaning that there’s room for three rows of seats – plenty of space for people and luggage. The battery placement gives the SUV a low and central centre of gravity.
Rear electric motor
Delivering 82hp (60kW) and 240Nm torque, the electric motor sits on the rear axle and drives the back wheels in electric and power-boost modes. The rear placement is significant because it allows for a larger motor, which is useful for following stop-and-go city traffic. This placement also makes all-wheel drive possible because each axle has its own power source.
The XC90 is the first car to be powered solely by Volvo’s new Drive-E engine range. It’s available to order from launch with either the AWD T8 Twin Engine petrol plug-in hybrid, an all-wheel-drive (AWD) D5 225hp diesel, or an AWD T6 320hp petrol engine.