Has anyone done a cost comparison between a kipps generator and a commerical CO2 generator?

mitessuck

Member
Did a search for "Kipp's" on here and found no results. Its an older method so that may be why. If someone has already looked into this and I missed it then I suck, but please be kind and hit me up with the right link despite my suckage.

Back in the day: before about 1940 in the US, you couldn't just buy a gas cylinder in a lot of places. So gas was generated in the lab as needed. But you didn't want to just dump a bunch of reactants together cause then you'd have a huge, uncontained gas cloud. And probably die with a lot of the gases they were making. A way was needed to make gas in a controlled way and automatically stop the reaction once a certain pressure was reached, enter Kipp's apparatus/generator. Its an old bit of kit, but super clever in how it works. Here's a vid (bit of a loud noise warning at the start )

It was mainly used to make H2S. But it can make anything that involves the reaction of two chemicals where one is solid and the other is liquid. If you mix calcium carbonate (marble chips) and hydrochloric acid (muratic acid aka concrete cleaner) you get a salt plus CO2 gas. This is how CO2 used to be made in the lab. In our grow areas we'd just crank the needle valve way down and let it run constantly through a water bubbler (to scrub out any vaporized HCl.)

I want to do a cost comparison between running a commercial CO2 generator, kipp's apparatus, and the fermentation method to see which works out cheaper per mole of CO2. Has this already been done?

Oh, if you know of other methods for making CO2 you want cost compared let me know and I'll do them too.
 

visajoe1

Well-Known Member
I want to do a cost comparison between running a commercial CO2 generator, kipp's apparatus, and the fermentation method to see which works out cheaper per mole of CO2. Has this already been done?
not sure there is many qualified stoners here to attempt this challenge, so please have at it!

i sure as hell aint playing with hcl in the future, but im curious about this experiment. best of luck
 

mitessuck

Member
Ha! Yeah, this isn't a solution for everyone. They do actually make them out of polypropylene too which is much less delicate. That said, if I were growing for my own use, and not for friends with health issues, I probably wouldn't be comfortable with it either.

Oversized delicate glass bong thing in my grow area filled with hydrochloric acid? What could possibly go wrong!

View attachment 5099719

I think I'll skip.
 

mitessuck

Member
not sure there is many qualified stoners here to attempt this challenge, so please have at it!

i sure as hell aint playing with hcl in the future, but im curious about this experiment. best of luck
Thanks for the info and encouragement.

This has turned into quite the research project. My conclusions so far are that the per mole cost of CO2 made from burning propane at current prices is about $.02 whereas the per mole cost of CO2 made by fermentation of a sugar wash (the yeast+sugar method) is about $1,26 or ~60 times more expensive (assuming a grower isn't making alcohol anyway and also ignoring equipment costs.) The yeast sugar method is so bad at making CO2 because most of the carbon in sugar is converted to alcohol by the yeast and therefore not released as CO2. Kipp's apparatus produced CO2 costs about .28 cents a mole and is cheaper than every other method I've looked at so far other than burning something.

I got curious and added in all the methods for making CO2 I could find to my research list. I'll post their relative costs here when I'm done. I think I'll also make another (more better) calculator because the current calculators are mostly assuming that everyone is using a gas cylinder. Some of us can't get gas cylinders economically due to where we live so we have to do something else.
 

visajoe1

Well-Known Member
how does this compare to mole cost on purchased co2? for example, 20lb tank with $20 refill cost or $50lb tank with $35 refill cost
 

Herb & Suds

Well-Known Member
Thanks for the info and encouragement.

This has turned into quite the research project. My conclusions so far are that the per mole cost of CO2 made from burning propane at current prices is about $.02 whereas the per mole cost of CO2 made by fermentation of a sugar wash (the yeast+sugar method) is about $1,26 or ~60 times more expensive (assuming a grower isn't making alcohol anyway and also ignoring equipment costs.) The yeast sugar method is so bad at making CO2 because most of the carbon in sugar is converted to alcohol by the yeast and therefore not released as CO2. Kipp's apparatus produced CO2 costs about .28 cents a mole and is cheaper than every other method I've looked at so far other than burning something.

I got curious and added in all the methods for making CO2 I could find to my research list. I'll post their relative costs here when I'm done. I think I'll also make another (more better) calculator because the current calculators are mostly assuming that everyone is using a gas cylinder. Some of us can't get gas cylinders economically due to where we live so we have to do something else.
I have no idea why you can’t get inexpensive co2 tanks sold and filled at literally all welding sales shops
But I concur it’s not needed
 

mitessuck

Member
how does this compare to mole cost on purchased co2? for example, 20lb tank with $20 refill cost or $50lb tank with $35 refill cost
That's a good refill price, or at least better than the welding shop I'm not willing to drive to quoted me, think they wanted about $3 a pound.

Here's my notes: A pound is equal to 454 grams. Since a mole of CO2 weighs 44 grams there are 10.32 moles per pound of CO2 (12+16+16=44) for a per mole cost of ~.29 cents per mole assuming CO2 is $3 a pound. This assumes 100% fill of the bottle and doesn't include any other expenses beyond the CO2 itself.

Since you're only paying $1 a pound it'd be about ~.10 a mole for you: cheaper than everything other than burning something.
 

mitessuck

Member
Ok :clap:
I live in a rural area just not Australia rural
Heh, yeah, I'm a bit out there. :) Thing is a lot of middle America is in the same situation. We're too far away from everything, both welding shops and weed stores for the easy solution to work out. Weed is legal in my state but the nearest weed shop is in the same city as the nearest welding shop. Certainly if you can just get a bottle refilled, have the money, and the grow size justifies it, then a bottle would make the most sense. That's what I'd do if I wasn't so far out.

Not gonna lie though, as a data guy the total lack of data online about how much of something you need to make a given amount of CO2 and how that translates to grow area is bugging me enough to make a free resource to answer that question, even if I'm the only one who ever needs it. I doubt that I will be, while researching this I found a youtube video of people filling a Dasani water bottle with some sugar and yeast and sticking that in what looked to be a 10' x 10' x 8' grow room. 16 ounce bottle in an 800 cubic foot room. That hurt my brain a bit. At least if I make a tool I can point the next fellow at it when I see stuff like that.
 

visajoe1

Well-Known Member
That's a good refill price, or at least better than the welding shop I'm not willing to drive to quoted me, think they wanted about $3 a pound.

Here's my notes: A pound is equal to 454 grams. Since a mole of CO2 weighs 44 grams there are 10.32 moles per pound of CO2 (12+16+16=44) for a per mole cost of ~.29 cents per mole assuming CO2 is $3 a pound. This assumes 100% fill of the bottle and doesn't include any other expenses beyond the CO2 itself.

Since you're only paying $1 a pound it'd be about ~.10 a mole for you: cheaper than everything other than burning something.
thanks for the math. i dont pay $1 per pound, but with these numbers we can calculate our true cost with a multiplier variable. thanks!
 

Lordhooha

Well-Known Member
Heh, yeah, I'm a bit out there. :) Thing is a lot of middle America is in the same situation. We're too far away from everything, both welding shops and weed stores for the easy solution to work out. Weed is legal in my state but the nearest weed shop is in the same city as the nearest welding shop. Certainly if you can just get a bottle refilled, have the money, and the grow size justifies it, then a bottle would make the most sense. That's what I'd do if I wasn't so far out.

Not gonna lie though, as a data guy the total lack of data online about how much of something you need to make a given amount of CO2 and how that translates to grow area is bugging me enough to make a free resource to answer that question, even if I'm the only one who ever needs it. I doubt that I will be, while researching this I found a youtube video of people filling a Dasani water bottle with some sugar and yeast and sticking that in what looked to be a 10' x 10' x 8' grow room. 16 ounce bottle in an 800 cubic foot room. That hurt my brain a bit. At least if I make a tool I can point the next fellow at it when I see stuff like that.
You should invest in a co2 burner
 
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