What the Media Missed About Environmental Impact
News outlets around the world covered the Colorado State University study’s dramatic findings, but most of them overlooked a major point: Marijuana producers already knew growing cannabis indoors was unsustainable.
"We didn’t blow the lid off of anything the industry knows. Their electricity and natural gas bills speak for themselves.”
But the study did finally put a number to what the industry already knew. To do so, Summers created a model that calculated how much energy warehouse growing operations across the country use to mitigate the weather outside. Then she compared those numbers against the grid mix—which sources are used locally to generate electricity, whether hydroelectric, natural gas, nuclear, or coal—to estimate the local greenhouse gas emissions. For a complete picture, the model also incorporated the greenhouse gases created “upstream” in the manufacturing process to produce things such as fertilizer.
One kilogram of dried cannabis produces between 2,283 to 5,184 kilograms of CO2, depending on the region where it was grown. Put another way, producing one ounce of dried weed is equivalent to burning seven to 16 gallons of gasoline, according to Smithsonian Magazine. Colorado’s variable weather and mixed power grid mean it’s one of the worst offenders. Marijuana cultivation accounts for an estimated 1.3 percent of the state’s total greenhouse gas emissions.
The Easy Fix,
would be shifting from indoor grows—which require massive amounts of energy to power the high-intensity lights that feed the plants, as well as to cool down those lights—to outdoor grows. Doing so could reduce greenhouse gas emissions by as much as 96 percent, according to the study. But making the switch is easier said than done, according to Alex Levine, chief development officer and co-owner of local cannabis retailer and cultivator Green Dragon.