I have a project to use 40-50 CCFLs taken from broken laptop screens as a floodlight for video recording (I'm not a professional so CRI doesn't concern me). I expect each inverter to consume about 4-5 W so need to expect up to 250 W heat (I guess ~50 W might be emitted as light though). Although the first C in CCFL stands for cold, I'm pretty sure they do get warm. I don't want to use a fan because it would affect the video recording. I was thinking of having the CCFLs on one side of a thick aluminium sheet (~4 mm?) and the inverters on the other. If it's okay to stack the inverters, I could attach heatsinks to vacant areas on the rear of the panel. There will need to be a clear plastic sheet affixed to the front of the panel to protect the CCFLs. Does this sound reasonable? The CCFLs were originally enclosed inside a plastic laptop screen case so presumably can handle being quite warm, I just don't know how warm.

 

Further research suggests that I will need to keep the CCFLs below 60 °C (20-30 °C is ideal but not realistic). I would have liked to use a passive solution but I suppose I could use fans if I keep the RPM really very low. For the passive solution to work I think I'd need to somehow physically connect the CCFL glass to the aluminium panels and that's tricky because of the diameter of the insulation at each end of the CCFL tube.
I made a short clip to try to explain my half-baked ideas in the hope that someone might be able to bake them a little further.

 

I have another small issue as well. I also have several broken desktop LCD screens and I want to use the power supply from those to supply the power to the laptop inverters. If you look at the below picture you see the power supply and inverter from a desktop monitor connected to the electronics involved in displaying a picture. I can replace the unwanted electronics with a resistor to provide the needed 3 V on signal. The issue is: how many laptop inverters can I power from the power supply that was meant to supply the unwanted display electronics? Could I apply increasing loads and check for the voltage sagging?

I've had a look at the back of a monitor that says it draws 0.7 A at 240 V. What translates to 168 W which is more than I was expecting. Assuming that the four built-in CCFLs use 8 W each, that would still leave 136 W. Assuming the power supply is only 60% efficient that leaves (168 W x 60%) - (4 x 8 W) = ~68 W. I've no way to tell how that's distributed across the 12 V and 5 V but if it's 34 W each then I can draw 2.8 A from 12 V and 6.8 A from 5 V?

I figure I can probably attach eight laptop inverters to each desktop PSU (four on 12 V (1.6 A) and four on 5 V (4 A)