
Apparently to destroy a planet, such a generator only needs to be modded to output 2.33*10^25J, as this is, in SG1, enough to destroy a planet when "innapropriately applied." That said, this isn't all that surprising, if Serita were a naquadah rich world, it would be crammed with explosives in much the same way Scooter claims Alderann was.
I'm no longer so sure that the RPG is entirely non canon, the more one looks at it, the more reasonable its claims become. Certainly if it were canon, it'd set a likely lower limit of 1,273,900,573 Mt/shot on the power of an ion cannon, which seems, frankly, obscene. Suddenly Naquadria planet shattering sounds sane.