Curbing the Cannabis Industry’s Appetite for Energy

November 12, 2018
Volume: 
1
Issue: 
4
Abstract / Synopsis: 

Cannabis cultivation has a problem, a big problem: the electric bill! Earlier in my cannabis career, I heard growers complain about the cost of electricity eating into their profits—but now the situation is much worse, while the stakes are far greater. Energy consumption is under greater scrutiny than ever by regulators because of concerns over fossil fuels hastening climate change and the cost of expanding the grid. This means the cannabis industry better find solutions to cut down on its power use, or else the government will—and no one wants that.

Just how bad is the energy problem in the cannabis industry? Energy inputs are estimated by several studies to be perhaps as much as half of total indoor cannabis cultivation costs. Based on this estimate, let’s assume 2000 kW/h per pound of medicine and a typical energy cost of $0.24 (1). For growing a single pound of cannabis, that’s $480 worth of energy! And just what is this energy used for? It’s not just lighting; also sucking up power are air conditioners and chillers, dehumidifiers, carbon and high-efficiency particulate air (HEPA) filters, fans, and system controllers. In a 2016 study done for investor-owned San Diego Gas & Electric, Evergreen Economics broke down the energy consumption for indoor cannabis production and found that lighting accounts for 38% of the energy consumed, venting 30%, and air conditioning 21% (2). Furthermore, when one considers the current means of energy production, the cultivation of 1 kg of cannabis results in the production of 4600 kg of carbon dioxide.

Clearly, there is plenty of room for improvement and, just as fortunately, there are many ways to improve. For now, let’s just talk about two: the cultivation structure and how it is illuminated. According to BOTEC Analysis, indoor cultivation has the highest energy consumption levels with 4400 kWh, 6100 KWh/kg. Greenhouses have much lower energy demands with 6 kWh, 580 kWh/kg (3). (BOTEC’s study considers the energy consumption of outdoor cultivation to be minimal.) This is why I recommend to cultivators that they start their site and structure selection process by giving serious consideration to a greenhouse.

In California, my home state, the Department of Agriculture has projected the following trends: There will be a shift in production from the northern to the southern part of the state while the use of controlled-environment agriculture (CEA) is forecast to jump dramatically over 2–3 years from 16% to more than 50% (4). I expect there will always be indoor, greenhouse, and outdoor production, and there are advantages to all these methods. Still, I would like to see the percentage of greenhouse facilities increase for the reduction of energy use while still enabling a controlled environment for maximum yield and quality.

Light emitting diodes (LEDs) are finding their way into more and more grows, despite skepticism by cultivators. Most of the controversy centers around sufficient power during the flowering phase and the nonsolar nature of the spectrum. Both concerns are not issues in the greenhouse, where LEDs serve to augment the solar spectrum during off-peak times of solar illumination such as early morning, late afternoon, winter months, and cloudy days. However, the energy benefits are real and substantial: Most manufacturers claim that their 600-W fixture can replace a 1000-W high-intensity fixture, resulting in a 40% reduction in lighting costs. This efficiency is further compounded by energy savings associated with cooling because of the heat produced from lighting; therefore, these practices are being adopted by CEA vegetable growers on a global scale. The reason is simple: LEDs save money by saving energy in the CEA setting while increasing yield and quality.

As the acceptance of cannabis spreads across the nation and world, it’s logical to assume more will be grown, which, of course, means an increasing demand for electricity. The industry would be wise to demonstrate its responsibility by acting now to cut back on power consumption. Because if cultivators don’t, strangers may be more than willing to act for them—and when they do, they may not have the industry’s wellbeing in mind.

An Expert’s Point of View

When looking for solutions to the cannabis industry’s high energy consumption, it’s necessary to have experts who are familiar with both cultivation and how utilities can help growers. Dan Duran has that knowledge, having worked for power companies and, as a professor, having researched cultivators’ use of power. Dan spoke with Cannabis Science and Technology magazine to share how the two sides can work together.

References: 
  1. J.P. Caulkins, “Estimated Cost of Production for Legalized Cannabis” (RAND Drug Policy Research Center, 2012).
  2. Evergreen Economics, “SDG&E Cannabis Agriculture Energy Demand Study” (Prepared for San Diego Gas & Electric Company, 2016).
  3. M. O’Hare, D. Sanchez, and P. Alstone, “Environmental Risks and Opportunities in Cannabis Cultivation” (BOTEC Analysis Corporation internal publication, June 2013).
  4. J. Remillard and N. Collins, “Trends and Observations of Energy Use in the Cannabis Industry” (ACEEE Summer Study on Energy Efficiency in Industry, 2017).
  5. Colorado Energy Office, “Energy Use in the Colorado Cannabis Industry” (Fall 2018).

How to Cite This Article

R. Kern, Cannabis Science and Technology 1(4), 18-20 (2018).