I see so many things addressed here but in flight power does not seem to addressed in any depth. The CX site addresses it thus:
Inflight laptop power
Need to keep your laptop computer running at full speed onboard? We offer you inflight laptop power! This service* is available to all passengers in First, Business and selected Economy Class. Inflight laptop power is available to passengers on a shared basis in Economy Class.The power output is 15 volt DC (75 watts) or 110 volt AC (100 watts)**.
Which planes have what type of power?
Naturally the reason I ask is because I am travelling on CX soon, CX134 MEL-HKG and then CX364 HKG-PVG both trips in Y on the A330.
I also see references to EmPower.
My last CX flight HKG-PEK (in J) had EmPower and the FA produed a kit which I was able to use to get power.
This FAQ thread is extremely useful but I can't seem to find any definitive information about in seat power.