Thanks Diver. Just managed to find the info myself - it was in the manual all along, must have overlooked it first time.
220-240V, 50-60Hz, 1150-1260W
It's the heater part of the equation that bothered me, but since it's only heating an espresso's worth of water at a time, I guess it won't be as hungry as a kettle or toaster or vacuum cleaner.
So it's probably OK to use it, just make sure nothing else is being powered at the same time...