How much difference does CO2 make?

[t7rln]

I was going to post the question "How much difference does CO2 vs regular air make in a grow?" Well a habit that I am getting better at is researching before I post a question, so that I can add some value to this community. I have already gotten so much info. from this collective knowledge.

Anyway here is one of the videos that I found interesting:

http://www.youtube.com/watch?v=YB29Mfw-HcU&feature=related

 

[antimatter]

Enough to make it worth it + more expensive to set up but if you live in a cool climate and were to max out a 200 amp service + run a flip and air cool you can run quite a bit more lights without Co2 and can take the summer off from growing. Fly by night op no acs/dehuey just lots of 2000+ cfm exhaust fans. But in the end you can get more with less + faster veggin with co2 and in the cool climates the lights off temps may not be perfect if your maxing out your amps.