Federation warp core

Here we see Data sitting on warp core. Brent Spiner, who plays Data, is 1.778 meters tall. Eyeball estimate of warp core diameter gives us around 90 centimeters in diameter; however, part containing fuel is more like 54 cm in diameter. Matter-antimatter reaction seems to go in pulses, 1 pulse per second, with pulse length of around 100 centimeters for volume of 0.229022 cubic meters. Given that 2 pulses react with each other, that volume is 0.458044 cubic meters.

If we take deuterium/antideuterium, that is total reactant mass of 0.08 kg per second or 59 545 720 kilograms of ultra-dense deuterium and its antimatter equivalent per second.

So we can calculate standard energy output of 7.2 x 10e15 watts or 7.2 PW for standard deuterium or 5.36 x 10e24 W (5 360 000 000 PW) for super-dense deuterium. However, one must note that "standard output" is output during normal subligh operations, i.e. warp drive disengaged, weaponry is not used etc. Maximum output might be as much as ten times greater.

Episode evidence

In "True Q"[TNG6], we hear the following exchange occur in Engineering:
Amanda: "It's hard to imagine how much energy is being harnessed in there."

Data : "Imagination is not necessary; the scale is readily quantifiable. We are presently generating 12.75 billion gigawatts per . . . "

One must understand that gigawatts per anything is actually gigawatts per anything. "Anything" here can stand for volume etc (it can't for mass beacouse, since it is M/AM reaction, energy gained from mass is always E=mc^2).

12.75 billion GW is 1.275 x 10e19 joules per second, which translates into 141.86 kilograms of fuel annihilated. Ultra-dense deuterium has density of 140 kilograms per cubic centimeter. Coincidence? I don't think so.

With that, we can calculate total output of E-D warp core to be 5.84 x 10e24 W or 5.84x10e12 TW (5 840 000 000 000 TW or 5 840 000 000 PW).

As for Star Wars power generation, see here:
http://www.st-v-sw.net/STSWimpower.html

UPDATE: Another possibility is that he was about to say "per pulse", which would lower total power production to 4.25 billion GW. That is equivalent of 1 gigaton per second.

UPDATE 2: In script, Data does say "per second".

On my site.