Originally Posted by
Retro Grouch
So where does the CO2 in CO2 cartridges come from? Assuming that it comes from the air, we haven't added or subtracted anything by using it in our bike tires.
Planting trees is only a temporary solution. Eventually the trees will die and decompose, then all of the CO2 they hve absorbed during their lifespan will be reabsorbed into the atmosphere. It's kind of like storing it in a bike tire.
There are a zillion more important environmental issues than CO2 cartridges, but to evaluate the impact you'd have to look not only at where the gas comes from but also how it got compressed to 900 psi.
Commercially produced CO2 a biproduct of other processes such as ammonia production - so if they didn't collect it and put it in tanks, they'd just be bleeding it into the atmosphere (if it weren't for greenhouse gas emissions limitations). And compressing it involves electrical or gas-driven motors. Probably ought to include transportation costs to get the carts to your LBS too.
I've used about 12 carts in the last 5 years... my conscience is clear.