HPS run cooler than CFL?

So I've been reading a LOT about lighting. I've got a Rubbermaid setup that I will run about 10 26w (100w equiv.) cfl's. I have a 150 cfm pc fan for exhaust, two 2" holes for intake, an 80 cfm pc fan blowing at the lights and a small desk fan for air circulation. It stays about 8 deg. warmer in the box than ambient room temp. Now for all the heat per watt the cfl's produce, it sounds like I could put a 150w HPS in my box (prolly about 8 to 10 cubic feet) with the 150 cfm fan pulling air off the light (and out of the box) through a carbon scubbern abd it would create less heat than the 10 cfls!? Any ideas?

IMHO, I think the 150 HPS would be significantly hotter than the CFL's. You would need a cool tube with plenty of CFM's to haul away all that hot air. I have ZERO experience with rubbermaid grow thingys but I have alot of experience cooling a 4' X 3" X 6" Flower cabinet using a 400 HPS and that puppy puts off alot of heat. Good luck to ya!

That's what I am told, but I keep coming back to this FAQ article:

Especially this:

"Comparatively inefficient. 10 forty watt fluorescent bulbs use the same amount of energy as a 400 watt HID, but produce far less light. Since they use the same amount of energy but produce less light, the remaining must be given off as heat. Contrary to how it may first appear, fluoros actually run hotter than the equivalent wattage of HID-- they just disperse the heat over a wider area."

150 watts isn't a lot, it's be a few less than what my cfls are using (but of course they put out much more in equivilent) So wouldn't it generate less heat than these CFL's? And 150w HPS would be plenty for a small space?

I have my room divided into 2 chambers. 2 x 70w HPS for flowering and 1 x 42, 1 x 23w CFL for vegging (more, but only 1 plant at the moment so that is all I leave on) and the veg side is def. hotter.

idl said:

I have my room divided into 2 chambers. 2 x 70w HPS for flowering and 1 x 42, 1 x 23w CFL for vegging (more, but only 1 plant at the moment so that is all I leave on) and the veg side is def. hotter.

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Do you have the same ventillation on both sides? How big is your flower room?

i just switched all my cfl's to a 400w hps last week and it's cooler now that before. 3 fans plenty of ventillation. nothing changed but the light, but def cooler

the dude up there is right... 150 watts of hps will put out the same heat as 150 watts of Cfl the only diffrence is how the heat is disburst ... in a hps all of the heat is given off over a few inches of space so the heat will be much more intense... but in a cfl there is alot more surface area so the heat will be less intense.... the only diffrence really is that u can get ur plants closer to cfls (due to less intensity)

OSHiT said:

the dude up there is right... 150 watts of hps will put out the same heat as 150 watts of Cfl the only diffrence is how the heat is disburst ... in a hps all of the heat is given off over a few inches of space so the heat will be much more intense... but in a cfl there is alot more surface area so the heat will be less intense.... the only diffrence really is that u can get ur plants closer to cfls (due to less intensity)

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Right, and you HAVE to get them closer to CFL's to take full advantage of the light. While with HPS you can have it many inches to a foot away and still get the intenses light to the plant. So if you get airflow over the bulb and exhaust the grow box (just like you have to do with CFL's) it should be cooler. This is what I'm stuck on. It's pretty much a debate over cooling and ventillation, because to have sufficient light in a grow area there's going to be a lot of heat generated. You can have sufficient light with LESS HEAT PER WATT with an HPS, or sufficient light with MORE HEAT PER WATT with CFL's. You must have adequate wattage for the grow area, so if it came down to the EXACT same growbox set-up with IDENTICAL venting, the HPS would run cooler at the same amount of watts used.