The recent rise in the industrial cultivation of Cannabis has been attributed to a desire to reduce criminalization and improve security, pest and disease management. In the United States, 15 states, including the District of Columbia, have legalized the cultivation of Cannabis, in which an estimated 28.5 million Americans are estimated to be repeat consumers. Additionally, the cultivation of Cannabis is also estimated to have an annual market value of $7 billion.
The cultivation of Cannabis has not only significantly improved the economy for numerous countries around the world, but its potential as a renewable energy source is also promising for these countries. Before this can occur, an analysis of the typical processes required for the production of Cannabis, as well as any potential environmental effects of its cultivation must be considered.
The Energy Requirements of Cannabis Cultivation
The cultivation of Cannabis requires an extensive amount of energy, particularly for the indoor production of this plant. For example, the lighting levels of a typical indoor Cannabis facility match those found in hospital operating rooms, which is 500 times greater than that which is recommended for reading.
Additionally, these indoor facilities also require 30 hourly air changes, which is comparable to high technology laboratories that require 6 times less as many air changes. As a result of burning propane or natural gas to improve plant growth, the carbon dioxide (CO2) levels in indoor Cannabis facilities are often raised to levels that are 4 times as high as natural levels, which contributes to approximately 1-2% of the carbon footprint each year, as well as a U.S. expenditure of approximately $0.1 billion.
Additional specific energy uses of Cannabis cultivation plants include:
- High-intensity lighting
- Dehumidification to remove water vapor and avoid mold formation
- Space heating
- Space cooling
- Pre-heating of irrigation water
- Generation of CO2 by burning fossil fuel
- Ventilation and air conditioning to remove waste heat
Environmental Impact of Cannabis Cultivation
To put the energy requirements of Cannabis cultivation into perspective, consider a single Cannabis cigarette is equivalent to:
- 1.5 kilograms (3 pounds) of CO2 emissions, which is equivalent to:
- Driving a 44 miles per gallon (mpg) hybrid car for 22 miles
- Running a 100-watt light bulb for 25 hours
In fact, it is estimated that the production of one kilogram of processed Cannabis is equivalent to 4,600 kilograms of CO2 emissions to the atmosphere, which increases by 50% when off-grid diesel power generators are utilized in the cultivation process. The substantial amount of emissions produced during the cultivation of just one kilogram of Cannabis is further estimated to be equivalent to driving across the country 11 times in a 44 mpg vehicle1.
The current legislation on the production and distribution of Cannabis fails to consider the significant energy consumption, costs and potential greenhouse gas pollution associated with these processes. A more in depth analysis and improved transparency of the energy impacts of Cannabis cultivation must therefore be performed to ensure that the adverse impacts are considered.
For example, the elevated moisture levels that are associated with the indoor cultivation of Cannabis can potentially cause extensive damage to buildings, as well as promote electrical fires as a result of a failure to meet safety code requirements.
Researchers believe that by shifting production of Cannabis to outdoor locations could significantly improve the environmental impacts associated with these processes. Once this shift takes place, further consideration into transforming Cannabis, or hemp, as a potential energy source may occur.
As a crop, hemp exhibits a good resistance to drought and pests, a well-developed root system that is resistant to soil erosion, as well as a much lower water requirement as compared to other crops like cotton. Hemp is therefore a highly versatile fiber crop that is particularly unique for its possession of both a high percentage of useful oil and biomass components.
- Mills, E. (2012). The carbon footprint of indoor Cannabis production. Energy Policy. DOI: 10.1016/j.enpol.2012.03.023.