There are two different numbers used here with different connotations.
Kwh is killowatt hours, which is refering to battery capacity.
Kw is killowatts, which is refering to the power output of the motor.
So in this case, if the motor were running at 2 Kw for an hour, it would have expended 2 Kwh of battery.
So this may not sound like a lot, but actually it is quite sufficient for a hybrid. Most of the time when your driving your usually staying within a range of speed. This requires little power (less than a Kw). This is the reason why on a fairly level freeway, the current VGL gets good gas mileage.
You'll probably get higher burst coming off the line, or for when your passing. In this case, you'd probably temporarily hit 20-50 Kw for maybe 30 seconds or so. Sounds like a power hit but not for that power pack. Let's take the middle of the range (35 Kw) for 30 seconds (30/3600 seconds) gives us the power consumed (.29 KwH).
The full power would only be utilized under extreme circumstances. But in order to drain the battery from a full charge, you would have to maintain full acceleration (gas/electric) for 15 minutes.
Throw in regenerative braking and the ability to plug in one should never have to worry about draining the system. Plus, you get a significant source of power at much better efficiency than an ICE.
Ok, that's enough nerd.
~X~