[Mark]

With BMW's X6 Active Hybrid now well advanced in its development
process, the appearance of this hybrid X5 is not entirely unexpected.
Spinning off the hybrid technology on the X5's largely related
platform seems a no-brainer in this increasingly fuel-conscious
environment.

If the huge hood bulge wasn't enough of a giveaway that a new hybrid
powertrain resides within the X5, the neon green warning sticker
affixed to the X5's backlight seemed to announce the state of affairs
plainly enough. It reads: "Caution: Hybrid-Prototype (High Voltage
On Board)."

The real question regarding this X5 Hybrid is whether it's running a
gasoline or diesel engine. BMW showed the X5 Efficient Dynamics
Active Hybrid concept at the 2008 Geneva Motor Show--which utilized
Munich's 2.0-liter, twin-turbocharged four-cylinder diesel engine in
combination with a 20 horsepower electric motor. This was a definite
break from the strategy revealed with the petrol-based Active Hybrid
concept shown on the X6. The X5's four-banger hybrid concept made a
healthy 201 horsepower, in conjunction with the torque-rich diesel's
output of 295-pound-feet at a low 2000 rpm. The electric motor
further augments the torque rating, for what promises to be enjoyable
launch and acceleration characteristics.

The X6 hybrids spotted testing to date have all been petrol-based. We
have yet to see this X5 hybrid fuel up, so we can't conclusively
answer the gasoline/diesel question just yet. However, the small
round exhaust tips on this prototype look closer to the standard X5
diesel exhaust rather than the larger, rectangular tips on the X5
3.0si. We'll be watching for a refueling session on this prototype to
put the issue to rest.

If this X5 is using the same engine as the gas-powered X6 hybrids,
then it would appear that the X5 is about nine months behind the
development curve when compared to the X6--judging by the prototypes'
respective appearances on the test circuit. Stay tuned for more
information.