(This is an old page using the DS9 Technical Manual as a reference, so take it with a grain of salt.)
Deep Space Nine uses the old Cardassian reactors to produce power. Were all six reactors functional, the station could produce 790 terawatts of power . . . however, considering the disrepair of the power generation components, only four reactors are fully functional with one as backup (see DS9TM, section 5.0) . . . this implies that the station normally produces some 525 terawatts of power.
The fusion reactors use focused pulse-wave laser detonators, 29 per reactor, to induce fusion in the deuterium pellets. The detonators converge 26.1 GJ of energy on a pellet, at a normal frequency of 12 times per second, though the rate can go as high as 83 times per second.
To find the power of these lasers, we should first divide 26.1 GJ by the 29 laser detonators. Doing so, we find that each detonator is capable of producing .9 GJ, or some 900 MJ.
To find the power of these lasers, we must attempt to determine how often they can produce .9 GJ on target. Of course, we have this . . . normal is 12, peak is 83.
Thus the effective sustainable "firepower" of these engineering lasers is as follows:
Normal: .9 GJ/.083333s = 10.8 GW
Peak: .9 GJ/.012048s = 74.7 GW
This is just one of 29 per reactor . . . one of 116 normally operating on the station. Using even my highest estimates of turbolaser sustained firepower, the simple *engineering* lasers of a rickety old Cardassian station are far superior to the sustained firepower of a Star Destroyer's turbolasers, and even the entire Star Destroyer.
And yet, UVD would have us believe that the tactical phasers aboard a starship, or even aboard DS9, are less powerful than a turbolaser. If phasers were so powerless against targets, why would they be used? Why not rip out some focused pulse-wave laser detonators from the station's reactors and put them on DS9's defense sails? The answer must be that phasers are capable of delivering far more bang for the buck than these little engineering lasers, be it against shield or hull. Otherwise, simple engineering lasers would be the tactical weapon of choice, instead of phasers.