The legalization of cannabis has caused a substantial increase in commercial production, yet the magnitude of the industry’s environmental impact has not been fully quantified. A considerable amount of legal cannabis is cultivated indoors primarily for quality control and security. In this study we analysed the energy and materials required to grow cannabis indoors and quantified the corresponding greenhouse gas (GHG) emissions using life cycle assessment methodology for a cradle-to-gate system boundary. The analysis was performed across the United States, accounting for geographic variations in meteorological and electrical grid emissions data. The resulting life cycle GHG emissions range, based on location, from 2,283 to 5,184 kg CO2-equivalent per kg of dried flower. The life cycle GHG emissions are largely attributed to electricity production and natural gas consumption from indoor environmental controls, high-intensity grow lights and the supply of carbon dioxide for accelerated plant growth. The discussion focuses on the technological solutions and policy adaptation that can improve the environmental impact of commercial indoor cannabis production.
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The custom computer code used to generate the results of this study, supporting data files for the code and data results from the code can be located through GitHub at https://github.com/haisummers/research.
Córdova, L., Humphreys, H., Amend, C., Burack, J. & Lambert, K. Marijuana Enforcement Division - 2018 Annual Update (Colorado Department of Revenue, 2019).
The U.S. Cannabis Report - 2019 Industry Outlook (New Frontier Data, 2019).
National Survey on Drug Use and Health: Trends in Prevalence of Various Drugs for Ages 12 or Older, Ages 12 to 17, Ages 18 to 25, and Ages 26 or Older; 2016–2018 (National Institute on Drug Abuse, 2018).
Anderson, B., Policzer, J., Loughney, E. & Rodriguez, K. Energy Use in the Colorado Cannabis Industry - Fall 2018 Report (The Cannabis Conservancy, 2018).
State of the Cannabis Cultivation Industry (Cannabis Business Times, 2020).
The 2018 Cannabis Energy Report (New Frontier Data, 2018).
O’Hare, M., Sanchez, D. L. & Alstone, P. Environmental Risks and Opportunities in Cannabis Cultivation (BOTEC Analysis Corporation, 2013).
Warren, G. S. Regulating pot to save the polar bear: energy and climate impacts of the marijuana industry. Columbia J. Environ. Law 40, 385–432 (2015).
Crandall, K. A Chronic Problem: Taming Energy Costs and Impacts from Marijuana Cultivation (EQ Research, 2016).
Mills, E. The carbon footprint of indoor cannabis production. Energy Policy 46, 58–67 (2012).
Wilcox, S. & Marion, W. Users Manual for TMY3 Data Sets (National Renewable Energy Laboratory, 2008).
Office of Atmospheric Programs Clean Air Markets Division The Emissions & Generation Resource Integrated Database (eGRID 2018) (US EPA, 2020).
Wernet, G. et al. The ecoinvent database version 3 (part I): overview and methodology. Int. J. Life Cycle Assess. 21, 1218–1230 (2015).
U.S. Life Cycle Inventory Database (National Renewable Energy Laboratory, accessed 2020); https://www.lcacommons.gov/lca-collaboration/National_Renewable_Energy_Laboratory/USLCI/datasets
ASHRAE Standard 62.2-2016. Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings (American Society of Heating, Refrigerating and Air-Conditioning Engineers, 2016).
Guidelines for Environmental Infection Control in Health-Care Facilities (Centers for Disease Control and Prevention, 2003); https://www.cdc.gov/infectioncontrol/guidelines/environmental/appendix/air.html
Chandra, S., Lata, H. & Khan, I. A. Photosynthetic response of Cannabis sativa L., an important medicinal plant, to elevate levels of CO2. Physiol. Mol. Biol. Plants 17, 291–295 (2011).
Inventory of U.S. Greenhouse Gas Emissions and Sinks Report No. EPA 430-R-20-002 (US EPA, 2020).
Office of Energy and Environmental Affairs Cannabis Energy Overview and Recommendations (Massachusetts Department of Energy Resources, 2018).
Cannabis Sustainability Working Group Cannabis Environmental Best Management Practices Guide (Denver Department of Public Health & Environment, 2018).
Booth, K., Becking, S., Barker, G., Silverberg, S. & Sullivan, J. Controlled Environment Horticulture Report No. 2022-NR-COV-PROC4-F (California Energy Code, 2020).
Madigan, M. J. Illinois House Bill 1348 (Illinois General Assembly, 2019).
Carah, J. K. et al. High time for conservation: adding the environment to the debate on marijuana liberalization. BioScience 65, 822–829 (2015).
Heald, S. Colorado Greenhouse Gas Inventory 2019 Including Projections to 2020 & 2030 (Colorado Department of Public Health & Environment, 2019).
Çengel, Y. A. & Boles, M. A. Thermodynamics: An Engineering Approach (McGraw-Hill Education, 2015).
ASHRAE Standard 90.1-2019. Energy Standard for Buildings Except Low-Rise Residential Buildings (American Society of Heating, Refrigerating and Air-Conditioning Engineers, 2019).
Fitz-Rodríguez, E. et al. Dynamic modeling and simulation of greenhouse environments under several scenarios: a web-based application. Comput. Electron. Agric. 70, 105–116 (2009).
Joudi, K. A. & Farhan, A. A. A dynamic model and an experimental study for the internal air and soil temperatures in an innovative greenhouse. Energy Convers. Manag. 91, 76–82 (2015).
Steinfeld, A. Cannabis & Water Regulation (The Water Report, 2019); https://www.bhfs.com/Templates/media/files/TWR%23181.pdf
Nemecek, T. & Kägi, T. Life Cycle Inventories of Agricultural Production Systems (Ecoinvent, 2007); https://db.ecoinvent.org/reports/15_Agriculture.pdf
Soil Feeding Schedule (FoxFarm Soil & Fertilizer Company, 2019); https://foxfarm.com/feeding-schedules
Environmental Management – Life Cycle Assessment – Principles and Framework ISO 14040:2006 (International Organization for Standardization, 2006).
Environmental Management – Life Cycle Assessment – Requirements and Guidelines ISO 14044:2006 (International Organization for Standardization, 2006).
Bare, J. Tool for the Reduction and Assessment of chemical and Other Environmental Impacts (TRACI) version 2.1 User’s Guide (US EPA, 2012).
IPCC Climate Change 2007: The Physical Science Basis (eds Solomon, S. et al.) (Cambridge Univ. Press, 2007).
Morelli, B. & Cashman, S. Environmental Life Cycle Assessment and Cost Analysis of Bath, NY Wastewater Treatment Plant: Potential Upgrade Implications 3–9 (US EPA, 2017).
Lee, U., Han, J. & Wang, M. Evaluation of landfill gas emissions from municipal solid waste landfills for the life-cycle analysis of waste-to-energy pathways. J. Clean. Prod. 166, 335–342 (2017).
Guggemos, A. A. & Horvath, A. Comparison of environmental effects of steel- and concrete-framed buildings. J. Infrastruct. Syst. 11, 93–101 (2005).
ArcGIS Pro v2.4 (Environmental Systems Research Institute, 2019); https://www.esri.com/en-us/home
Data Trends: Energy Use in Office Buildings (Energy Star Portfolio Manager, 2016); https://www.energystar.gov/buildings/tools-and-resources/datatrends-energy-use-office-buildings
U.S. Energy Use Intensity by Property Type (Energy Star Portfolio Manager, 2018); https://portfoliomanager.energystar.gov/pdf/reference/US%20National%20Median%20Table.pdf
We acknowledge the Colorado State University GIS Centroid for generating the US results maps, specifically E. Tulanowski, S. Linn and C. Norris. We also acknowledge individuals for their continued support in reviewing this work, namely D. Browning, D. Quinn, J. Barlow, D. Trinko, K. DeRose and W. Stainsby.
The authors declare no competing interests.
Peer review information Nature Sustainability thanks Melissa Bilec, Michael Martin and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Summers, H.M., Sproul, E. & Quinn, J.C. The greenhouse gas emissions of indoor cannabis production in the United States. Nat Sustain (2021). https://doi.org/10.1038/s41893-021-00691-w
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