Marijuana is one of the most energy-intensive crops in agriculture. This can be a problem for two reasons. First, and most obvious is that a high cost of production cuts into profits. Second, and less obvious is that the industry’s oversized carbon footprint is coming to the attention of regulators and environmental watchdogs.
Growers wanting to run “greener” operations and turn higher profit margins and avoid more regulations are in a race to improve energy efficiency.
Whereas outdoor growers use no electricity for lighting, cooling, or ventilation, the story is far different for indoor marijuana growers. But growing outdoors is not an option for many growers who are either required to grow indoors or receive insufficient sunlight to grow outdoors.
Although the energy costs are far higher, there are some benefits to indoor operations, such as total control over environmental conditions. But replacing the energy of the sun for 12 to 24 hours a day is no insignificant matter.
The energy needed to power the lighting itself can be costly, but it’s not the only energy cost that comes with indoor grows. Air-conditioning and ventilation systems are required to prevent lights from overheating and to keep temperatures from rising too high for optimal growth.
Add it all up, and you have got yourself a whopper of an electric bill. The monthly electricity bill for a 10,000-square-foot indoor grow can easily run well into the six-figure range.
Growers can reduce their energy consumption for both lighting and cooling by using LED lighting designed specifically for cannabis growers, though LED lighting systems have their pros and cons. Although they consume far less energy than the typical 1,000-watt bulbs which many growers use, some feel that they produce inferior products.
Some growers utilize solar panels rather than gas generators or the power grid. Although that doesn’t decrease their energy demands, it does reduce their carbon footprint.
Solar energy and LED lighting are only part of the solution. As time goes on strains are being improved to flourish under indoor lighting and nutrient science is progressing allowing for high production under the same amount of light.
Climate Resources Group is an organization that works to avert the impacts of climate change. Sam Milton, the organization’s principal claims that indoor cannabis cultivation is approximately 8 to 10 times more energy intensive than the average commercial office building.
In a letter to regulators in Massachusetts, Milton wrote, “Indoor growers need to effectively re-create a blazing sun for 12 to 24 hours a day, every day. They do this by typically placing 1000 [watt] lamps every four or five feet in their grow rooms. But, of course, you don’t want to burn and rot the plants, so you need to cool and dehumidify the grow rooms, which also takes enormous power.”
Jim Borghesani of the Marijuana Policy Project says the industry is keenly aware of the need to conserve energy.
“Energy conservation is a major issue for any indoor growing operation, it doesn’t matter if it’s cannabis or any other crop,” he said. “They have an enormous incentive to shave off dollars from their energy bills. They’re going to do that regardless of any arbitrary guidelines the state decides to put into place.”
International cannabis expert Chris Conrad says the efficiency of indoor grows has increased dramatically since the 1980's.
“This has been a 30-year process of bit by bit improvement,” Conrad said. “But indoor grows can never match outdoor and greenhouse grows for energy efficiency or lowering CO2 output. We need to increase the use of natural sunlight to bring down our energy footprint. Also, indoor gardens often add CO2 to the garden’s atmosphere, whereas we should be focussing on bringing down CO2 output.”
Growers and states are working together to increase efficiency and reduce energy consumption - states because they need to meet their goals of reduced carbon output, and growers to increase their bottom line.
It’s worth noting that businesses in other industries which work to reduce their energy consumption can apply for energy rebates from local utilities. But power companies which receive federal subsidies are reluctant to provide rebates to an industry that is still illegal under federal law.
According to a story in the Salem News, Massachusetts state environmental regulators are concerned that the marijuana industry’s hunger for energy could jeopardize efforts to reduce the state’s carbon footprint. Some are calling for strict energy limits for cultivators.
In a letter to regulators, Tori Kim of the Executive Office of Energy and Environmental Affairs recommended that rules be put in place to regulate things such as lighting density. Under Kim’s plan, growers would have to show that they are within prescribed limits in order to be licensed but might receive exemptions for using renewable energies, such as solar or wind.
Massachusetts has been ranked the number one energy-efficient economy by the American Council for the past seven years. However, in 2016, the state Supreme Judicial Court ruled that Massachusetts must set annual limits on greenhouse gas emissions in order to comply with the Global Warming Solutions Act, a federal law the state adopted years ago. Massachusetts is working to reduce its carbon footprint by 25 percent from 1990’s levels within three years, and 80 percent by 2050.
Sam Milton says state officials have a duty to steer cannabis users toward more sustainable growers.
“The state is trying to find a balance between mandating growers to meet specific energy and environmental standards, while also providing consumers with the ability to differentiate between more environmentally friendly growers and manufacturers and the rest,” Milton wrote. “I think the state will need to [do] both, and only then will we see Massachusetts set the standard for responsible cannabis cultivation and manufacturing processes.”
In Denver, CPR News obtained data from the city’s Department of Public Health and Environment which shows growers accounting for four percent of the city’s electricity use. But it also shows that the amount of energy used per pound of marijuana is falling.
As with Massachusetts, Colorado is working to reduce its carbon footprint. Denver city officials have set a goal to reduce greenhouse gas emissions 80 percent by 2050.
Because this industry is so new, its energy consumption and carbon footprint are expected to continue to rise for several more years while growers work on more efficient technologies.
Although the demand for marijuana is increasing, due to growth in production the price per pound of marijuana has seen steady decreases. Last year, production in Colorado increased 23 percent from 2016 figures.
Kamani Jefferson, president of the Massachusetts Recreational Consumer Council, said he hopes the potentially high carbon footprint produced by marijuana farms doesn’t affect how the emerging industry is perceived.
“It’s definitely something we need to be cognizant of and we need to definitely ask questions and want to learn more about it,” Jefferson said. “When you’re rolling out a new industry, you definitely don’t want to cause more harm to this planet, so it’s definitely something to be on the lookout for.”