This was posted in another thread, but thought it'd be worthwhile to put in here for anyone considering adding CO2 (as well as if anyone wants to check my math).
Quote:
Originally Posted by
smokingrubber
I thought you just refilled those? How long are the tanks lasting? Please keep us informed on your generator hunt. "WE" need one that doesn't have to be in the tent. Have to make sure filling the propane bottles isn't more frequent and more $ than filling the Co2 tanks.
I refilled them the first (and only, so far) time (hold on, checking picture dates) on October 27th, but didn't start using my big tent until November 10th.
So, have gone through three tanks in about 30 days, but to be fair, 24 of those days were vegging with the CO2 running 24/7, and the first tank that I put on I installed incorrectly and let a lot of the gas out.
Regardless, propane is much, much, much more efficient then bottled CO2.
Using the link below and running some numbers (one pound of liquid CO2 is equivalent to 7 pounds of gaseous CO2, so each 20# tank gives you 140 cubic feet of gas), the numbers are overwhelming.
One 25# tank of propane will get me 2700 cubic feet of CO2, whereas each 20 pound bottle gets me 140. That's more then 19 times as efficient.
https://www.greenair.com/page/co2-ge...ing-chart.html
EDIT: even taking into account that the delivery system for CO2 is more efficient with a regulator and tanks, it's nowhere near worth the time and money of getting them refilled every 30-50 days. Also, there's nothing shady about getting a propane tank filled, whereas I'm anticipating some shady looks from the welding supply store guys already, and am somewhat dreading if I have to go again in another month or two.