What is it?
The new BMW X5 plug-in hybrid (PHEV) has gained two extra cylinders yet somehow become more economical (officially) and more BIK tax-efficient at the same time.
This feat has been achieved primarily thanks to a significant increase in battery capacity: it’s now 24kWh, up from just 9.2kWh in the previous-generation X5 xDrive40e.
That’s a key upgrade mostly for the difference it makes to electric-only range and associated tax qualification. As of April 2020, PHEV company cars will be classified not only on their WLTP-rated CO2 emissions but also how far they can be driven on electrictity alone. So, while most rivals have significantly smaller batteries that enable them to do no more than 20 miles or so under electric power, the X5 will be rated to go as far as 54 miles without necessarily exciting its reciprocating pistons.
The difference that could make to monthly running costs, even between running one of these instead of what you might take for a pretty competitive rival, could be significant. While owners of PHEVs rated for 40 miles of electric range or more will be due to pay just 8% of the car’s value per year as benefit-in-kind (BIK) tax, those who own alternatives good for less than 30 miles will have to pay 14%, and plenty will have to pay more still. That means the X5 could save a 40% taxpayer more than £200 per month over its rivals, and compared with a diesel, possibly twice as much.
This new X5 is one of several revised PHEV models introduced by BMW throughout 2019, all of which have what it calls its fourth-generation hybrid battery technology. Like the 530e, 330e and forthcoming X3 30e, it uses a longways-mounted engine and an electric motor mounted between that and the eight-speed automatic gearbox, where you might expect to find a torque converter.
Unlike the fleet-friendly petrol-electric 3 Series and 5 Series models, though, the X5 adopts the 282bhp turbocharged six-cylinder 3.0-litre motor that also powers the 745e. Given that this is good for 111bhp, total powertrain outputs are 389bhp and 442lb ft, leaving the X5 close to the Volvo XC90 T8 Twin Engine for potency, albeit not so close to the Porsche Cayenne E-Hybrid.