Congressmen Earl L. “Buddy” Carter (R-GA) and Doug Lamborn (R-CO) touted statistics from several studies, one of which were over ten years old, in an attempt to portray cannabis as an environmentally unfriendly plant, framing their argument around increasing competition for energy and the high amounts of electricity and water cannabis plants use compared to other agricultural crops.

“The demand for prioritizing electricity uses and for increased energy efficiency is a growing concern for the American public,” the letter said. “It is essential that the nation understand the burden marijuana cultivation puts on the electrical grid and the environment.”

Many troubling statistics were included in the letter, many of which seemed to have been based on old growing techniques. The letter claims that four plants can use as many electricity as 29 fridges. This is not surprising when one considers that most commercial growers still use high-pressure sodium lamps of 1000W if they are not switching to LEDs that consume about 300 watts. Some growers may place up to 10 plants in a single light source.

The letter also espoused that “annual cannabis cultivation electricity demand will grow 65% during the next decade.” However, this does not take into account that if marijuana were legalized on a federal level and interstate cannabis trade were opened, many cannabis companies would opt to move from an indoor grow model to an outdoor grow model.

You can find the letter addressed to the heads of the Department of Energy and the Environmental Protection Agency. They requested that congressmen respond to these questions no later than November 30.

• What impact does the current legalization of marijuana have on state energy consumption?
• What would the impact of federal marijuana legalization on national energy consumption?
• Is there an expected increase in energy use and emissions due to the pot industry?
• What will the growing demand for energy from the cannabis industry have on the reliability and availability of the electric grid?
• What impact do illegal marijuana growing operations have on the country’s water supply?
• What harms do illegal marijuana growers’ use of various fertilizers, herbicides, and pesticides pose to wildlife, habitats, and humans in the United States?

In a recent study, early 2021 showed that even though cannabis is grown on a large scale, it still requires very little water. These policy recommendations were made by the study to make sure that cannabis legalization doesn’t cause an additional strain on the environment.

1. Land use: as cannabis has traditionally been grown in environmentally-sensitive areas, planning could minimize negative environmental impacts linked to cannabis expansion.
2. Water consumption: Many cannabis plants are located in places where water extraction can be controlled.
3. Pesticide usage: Human exposure to pesticide residues from cannabis is unique because they can be inhaled or eaten. Pesticide control must be extended beyond normal agricultural practices.
4. Energy consumption: Incentivizing the best practices in cannabis cultivation could help reduce the energy use of both indoor and mixed-light cannabis production.
5. Air Pollution: Prioritizing science-based best practice could help reduce pollution and other air quality impacts.

The full study contains more details about the policy recommendations.