Wow, you're seriously lucky to have that kinda space to grow ganja in! I wouldn't even PARTLY consider going LED in that kinda space. For example, let's say you get a 600w hps, not sure about costs for these things since I'm a LED junky. Let's just say $500 for the whole setup, cooltube, ballast, everything. With 2 of those beasts you could run a vertical setup, like heath's for example. You may also get more than 1g/w. If you have say, 100 clones, and each yields the same, at 1g/w, you're looking at 1200g. With vertical setups more than 2g/w have been reported, so this is just a ballpark guess.
Total power would be: 1200w of hps, whatever of fans, and whatever a/c, going with a ballpark of 1750w. Also assuming soil, and no electric wasted on water or air pumps. Costs would be(assuming $500 for 1 600w hps) $1,000 on lights, about 250 for fans, scrubber, etc, and another 100 for a/c. Let's round it off with $1,500.
Now let's compare LED: You purchase 2 of these 600w panels(not going to go into brands here). Let's say you get them at good price for $2,500. So you're looking at 1,200w of light, same as hps. With LEDs right now it can be a struggle to achieve 1g/w. So let's say you get .75g/w. 1200w/.75=800g.
You're looking at nearly a pound more with the hps system, and 2500 in lights vs 1500 for everything you need. Granted, LEDs won't require massive fans and an air conditioner, so you will save a little on costs there. Where LEDs pay off is you can use them for like 20 harvests whereas a hps bulb normally is only good for 1 maybe 2 harvests. If you want to experiment with LEDs, and you have the room to. Why not go with hps for a couple years to get some funds going for LED experiments? The LEDs will eventually outweigh the hps because you don't have bulb replacements to deal with.
It baffles me how many people have such large spaces and wish to use LEDs, they're simply just not there as far as large scale grows go. If you look at 90% of the LED grows going on right now, you'll see NONE of them are in a 5x5 area, let alone 11x11. If you find one that doesn't have HID included, let me know.
Stick to the hps, and run an air conditioner and you can then venture into the LED world, once your system is dialed in you can pull in thousands of dollars per month selling a good indica. That would give you plenty of cash to fork out for the insanely expensive LED panels.
Of course, this is just my opinion, so do what you will.
Good luck with whatever ya decide!
