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Growing an Ounce of Pot Indoors Can Emit as Much Carbon as Burning a Full Tank of Gas

View original article written by Alex Fox at

Comments from BCP Green

We track long term trends in the cannabis space, and this is news that can’t be ignored by investors, lenders and operators. It has come to light that cannabis is not as “green” as one would expect from the general ethos of consumers.

This study from Colorado State University, is going to start a conversation that will lead consumers (and state regulators) to start demanding outdoor grown flower, and will see regulators requiring massive operational changes to indoor growers (changing to LED lighting and buying carbon credits are most likely).

This will be especially important in Mid-West and Northeast states, where heating and cooling are far greater than California for example. However, knowing California, they will lead the charge on energy requirements, which will have ripple effects to other states as they create their cannabis programs.

Growing an Ounce of Pot Indoors Can Emit as Much Carbon as Burning a Full Tank of Gas

As more and more states legalize cannabis for medical and recreational use, demand for the intoxicating plant is increasing and around half of that commercial demand is being satisfied via fully indoor grow operations. A new study suggests that in certain parts of the country, these indoor grow houses are responsible for significant emissions of planet-warming greenhouse gases, raising questions about the environmental toll of the expanding legal cannabis industry, reports Krista Charles for the New Scientist.

The researchers behind the study, published this week in the journal Nature Sustainability, estimated that the emissions associated with growing 1 ounce of cannabis indoors is about the same as burning 7 to 16 gallons of gasoline, depending on where in the U.S. it’s grown.

These emissions come from the large amounts of electricity and heating required to keep the plants happy. Lighting is the most obvious energy sucking aspect of indoor pot production, but heating, cooling or, in some places, dehumidifying the air also requires huge quantities of electricity. Per the paper, many producers even pipe in carbon dioxide, which plants use for photosynthesis, as a way of accelerating growth.

“Policymakers and consumers aren’t paying much attention to environmental impacts of the cannabis industry,” Jason Quinn, an engineer at Colorado State University and senior author of the study, tells Dharna Noor of Gizmodo. “There is little to no regulation on emissions for growing cannabis indoors. Consumers aren’t considering the environmental effect either. This industry is developing and expanding very quickly without consideration for the environment.”

In a commentary about their research in the Conversation, the Colorado State University researchers write that in Colorado, for example, the weed industry’s greenhouse gas emissions (2.6 megatons of carbon dioxide) exceed those of the state’s coal mining industry (1.8 megatons of carbon dioxide).

According to the study, pot grown indoors in Southern California has the lowest emissions, with an ounce of dried cannabis resulting in the equivalent of 143 pounds of carbon dioxide being released into the atmosphere. The low emissions are thanks to the state’s power grid, which uses of renewable energy sources and benefits from the region’s mild climate.

The highest greenhouse gas emissions occur in the Mountain West, Midwest, Alaska and Hawaii, where keeping cultivation facilities at optimal temperature and humidity requires significant usage of electricity and natural gas. The study found the highest carbon emissions were in eastern O’ahu, Hawaii, with the equivalent of 324 pounds of carbon dioxide emitted per ounce of dried weed produced, per the ConversationREAD MORE