Kind of a silly question...

[sphelps]

I remember reading someone was successfully running a 250W bulb on a 150W electronic ballast.

[Aquattro]

I tried running 400s on a 250w electronic, next to no light. Maybe it's different with smaller wattages.

[mike31154]

Never a good idea to try making electrical components that are not matched in their ratings work. Asking for trouble IMO. Best case insufficient light, worst case fire hazard or exploding bulb/ballast. I'd even stay away from the overdriven T5 setups some folks rave about. A lot more heat for a little more light.