Help needed with cabinet grow

My cabinet is approx: Height-52", Length-21", Width-18".

My problem is that I having difficulties in finding a silent way of extractor air so that their is fresh air circulating.

Ive considered small squirel cage blowers & 5 x PC fans (12v) but because of the voltage Ill have to use too many batterys.

Any advice or links to any products that may help?!

Anyone..............

Radio Shack sells a 4 inch PC fan that moves 60+ cfm for around $25. Plugs in the regular household outlet. Great reviews. It's not silent, but moving air in never silent. A lot of people use this fan to cool projection TVs.

I use that fan. I wouldn't call it a PC fan, it's a 120VAC axial cooling fan. It's way heavier and thicker than any PC fan I've seen. It is of metal construction, and could chew up your fingers a little if you're not careful. I attach it to 4" duct and use it to pull hot air out of a very small nursery cabinet in which I'm running 60 watts of CFL. It works like a charm, keeping the temps below 85 F. It is surprisingly quiet for its size and construction, especially behind cabinet doors.

Ill check it out, thanks guys!