Closed Enviroment VS In and Out Vents

Was watching some videos on urbangrower.com and he suggest the perfect enviroment is when you dont have in and out vents. I was wondering any experienced opinions out there. It seems to me that your electric bill might rise a little bit in a closed room enviroment but this would sure make the enviroment easier to control. What do u think?

Anybody????

There are several different reasons why one would need an in or an out vent.

For example, if you are using HID lights, you may want to air cool them cause they get HOT. In order to air cool them, you need to either take the air from the room, through the light cooler (cool-tube or air-cooled reflector) and OUT, or else IN from outside the room and then OUT.

Another reason will be to get your plants some fresh air. Plants need CO2 to grow, so you need to supply them with fresh air or they will use up all the CO2 and then suffocate. Either you use bottled CO2 in your room, or you use a CO2 generator, or else you need to draw fresh air IN from outside the room, to get your plants their CO2.

If you are drawing fresh air in from outside for CO2, then you need to exhaust air somewhere. In other words you need to get rid of the old CO2-depleted air inside, to make room for the new fresh air. So you need to exhaust that old air OUT of your environment, which would require a vent.

Some folks use this fresh air intake/exhaust system to control temperatures as well, which will work as long as the temps outside don't get too hot or too cold. If they get too hot or too cold, you need some sort of temperature control, like an A/C, in which case you will need more in and out vents.

Those Urban Grower videos are awesome. The guy is a shill for Advanced Nutrients, but who cares? The grow rooms he visits are impressive, and they are all of the closed environment type. They use big chillers and co2 generators, and the buds get big as footballs.

I thought the videos that included segments by Tech Mike are especially informative, but the whole series is very good. There are currently 38 episodes---quite a production.

The show is shot in B.C., and it's interesting that the sealed-room technique seems to stop at the US border. Also, in BC they seem to like hanging the lights vertically with no hood. The yields speak for themselves. The sealed-room technique obviously works.