BURLINGTON, Vt. (WCAX) – Growing the green stuff just got greener in the Green Mountain state.

A recent study out of Colorado found growing marijuana indoors can emit as much as 5.5 tons of CO2 equivalent per kilogram of dried weed.

That adds up, so one Vermont grower tracked down a more environmentally friendly method.

Long-time friends John and Justin bonded over sister industries – beer brewing and cannabis growing. When an opportunity bubbled up to fuse the two, it was a no-brainer.

“I’ve been dreaming about this for like a couple of years and one day I pulled John, I was like, ‘Hey, are we doing this?’ And he was like, ‘If I say I’m doing something, I’m doing it,” said Justin Kuehnl of Medicine Man Craft Cannabis.

They’re talking about CO2 recapture.

The Alchemist Brewery in Stowe used to release over 30,000 pounds of CO2 produced during fermentation into the atmosphere every week. A few years ago, they found a better use for it.

“The idea of sharing it with Justin for his cannabis production was just, you know, kind of a match made in heaven,” said John Kimmich of The Alchemist Brewery.

Kimmich’s team hooks their fermentation tanks up to a CO2 recovery system created by Earthly Labs.

They use 70% of the recaptured gas in-house for things like packaging.

Kuehnl picks up the rest of the stash every week, bringing it back to his business in Marshfield.

“It literally smells like a brewery,” said Kuehnl.

Marijuana plants, like all plants, require CO2 to grow.

Kuehnl used to spend thousands of dollars on propane to produce the gas, but now he feeds them for free, all while preventing waste.

“It’s a completely clean product, as opposed to the past where it’s kind of dirty there,” he said.

With double the amount of CO2 to draw from, Kuehnl says he doubled his growth.

The extra revenue helps his small business compete with bigger fish.

“I’ve actually had rooms that are half empty because we had such a fast turnaround and such a heavy yield, so win-win,” said Kuehnl.

On The Alchemist brewery’s end, the recapture tech wasn’t exactly cheap, costing them over $100,000.

But Kimmich says they were willing to pay the price.

“We’re looking at it from the standpoint of responsibility, and there’s a price to that, and we’re willing to absorb that price to do the right,” he said.

Breweries across the country are tapping into the tech, though The Alchemist is the only known Vermont brewery recapturing CO2 for cannabis growth.

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