Weed culture is linked to the image of earthy types who prefer bare feet to Nikes and black bean burgers to bison bacon burgers. But headlines over the past few years show the environmental impact of the marijuana industry isn’t as green as the stereotype would have us believe.
A recent study by Colorado State University mechanical engineering grad student, Hailey Summers, showed that growing marijuana requires an extreme amount of resources. The article, published in Nature Sustainability, details the industry’s environmental impact which accounts for a staggering 1.3 percent of Colorado’s total emissions. For perspective, coal accounts for 1.8 percent. The main cause? Growing indoors.
How the marijuana industry shielded plants from the sun
Multiple factors contributed to the surge or indoor grow facilities, starting with regulations. In the early days of legal weed, the law only allowed for vertically integrated operations, meaning dispensaries had to grow and sell products all in one place. Many counties banned outdoor growing where crops couldn’t be locked up. Some laws have changed since, but operations have remained the same.
Many cultivators prefer being indoors, anyway, due to the climate control and ability to produce multiple harvests per year, opposed to only one. But the heating, cooling and ventilation systems are ravenous for energy and the attribute the most greenhouse gas emissions. The second biggest energy eater is the lights, followed by funneled-in CO2.
Plants need to breathe, so facilities need to bring in fresh air to keep the plants growing happy and healthy,” Summers told Extract Labs. HVAC equipment has to constantly modify temperatures and humidity air, which takes immense power. Those systems are run off of either electric or natural gas, she says.
HVAC equipment works overtime in places like Colorado. Last September, temperatures went from 90 degrees to below 30 with snow in less than a day. This is an extreme example, but Colorado weather is known for its Kathy-Bates-in-Misery mood swings. It requires more energy to keep indoor temps consistent in such a dramatic climate. Her model showed that a grow facility in balmy Southern California, where temperatures are consistently warm and people are consistently tan, would result in 50 percent fewer emissions than an indoor Colorado farm.
Despite the energy expense, the control indoor farms provide is difficult to give up because it results in a consistent end product with commercial appeal. Outdoor doesn’t have the same glimmering sticky dazzle of the warehouse-grown roided-out counterpart. THC strength has increased 300 percent from the mid-90s to 2017 due in part to indoor grows. Summers points out it’s easy for geneticists to develop high potency outdoor plants — they have — however, the control and consistency of indoor operations disappear. Humble outdoor weed can’t compete with the market’s high tolerance and high-brow tastes.
Outdoor-grown hemp creates far less emissions
The Sunny Side of the Cannabis Industry
Some marijuana producers are doing their best to recycle and counteract emissions. For instance, The Clinic marijuana dispensary recycles carbon dioxide produced from Denver Beer Company’s fermentation to grow their plants. Recently, Boulder County launched a Carbon Conscious Certification for cannabis cultivators. The CCC stamp shows consumers they are supporting companies that offset emissions. While outdoor marijuana farms like Pot Zero, a zero-emission operation out of Gypsum, CO, do exist they are often the exception.
In the CBD industry, however, farming outdoors is the rule. Hemp grown by good ol’ fashion sunlight eliminates the need for 24/7 climate control, lighting, and piped-in carbon.
Summers’ compared her study to another researcher’s model on outdoor agricultural emissions. That comparison showed moving marijuana outside could reduce emissions by a whopping 96 percent. But Summers said the outdoor model was missing some key components, so the next step in her research would be collecting better outdoor data . She says studying hemp agriculture could be helpful in gathering that information since the crops are close relatives.
In addition to being a study subject, hemp is proven to absorb more CO2 than any other commercially grown product. The hearty plant requires limited maintenance, regenerates soil and promotes biodiversity. Growing cannabis outside not only reduces output, it gives back.
How the marijuana business can improve as it expands
As the world shifts its focus to the climate crisis, the hemp industry can serve as an analog for what the weed industry could be. Summers’ study shows that 80 percent of the marijuana industry’s greenhouse gas emissions are due to indoor practices. While cultivating outdoors doesn’t eliminate emissions, it’s far lower than indoor grows. Summers said we just don’t have that exact number yet.
The biggest challenge is changing consumer tastes. We live in a visual world where looks matter and there are preconceptions of quality. Summers suggests a hybrid-approach utilizing outdoor greenhouses and moving plants indoors only during later-stage development. She also says outdoor crops could be used for edible products where visual cues are no longer relevant.
As more and more states legalize cannabis, the environmental issue is likely to get worse. That marijuana still evokes images of 60’s peace and love hippies whose climate-conscious values would seem “baked” into the meme itself, remains an irony lost on many. While some companies are directing efforts for cleaner production, the overall appearance of what the marijuana industry represents — natural, earthy, healthy — isn’t as it seems. The hemp industry represents a cleaner approach for cannabis lovers who equally love the planet.