Missouri River Energy Services, in collaboration with the Electric Power Research Institute and with funding from the American Public Power Association’s Demonstration of Energy Efficiency and Development program, recently completed a study exploring how indoor agriculture, or controlled environment agriculture, can benefit public power utilities’ grids and communities.
The benefits of controlled environment agriculture (CEA) include water efficiency, land conservation, and increased food security and safety, thanks to the enclosed nature of CEA facilities and their proximity to consumers. For electric utilities, CEA also offers stable and predictable demand, distributed growing locations to reduce the need for long-distance power transmission, and increased energy efficiency.
MRES, a joint action agency comprising member municipalities in four midwestern states, sought to provide a case study for CEA’s potential impact on energy consumption as climate change continues to affect growing practices. Specifically, the study examined “energy consumption of a storage container…outfitted for food production with the addition of horticulture lighting, HVAC equipment, irrigation, and monitoring equipment,” with the additional goal of understanding what portion of that energy consumption could be shifted to off-peak hours.
Conducted from January 2020 through March 2023, the project significantly exceeded its original timeline as a result of staffing changes and complications arising from the COVID-19 pandemic. Over this 38-month period, the project gathered the intended 12 months of data.
MRES leveraged its $125,000 DEED grant toward the purchase of a storage container from Freight Farms, which delivered the container to the South Dakota State University campus in January 2020. Freight Farms provided training for people associated with the project, including students and staff from SDSU, and EPRI added sensors for remote data collection.
The container was outfitted to produce leafy greens year-round in a zone 4b climate, which the USDA denotes as featuring an average annual minimum temperature of between -25 and -20 degrees Fahrenheit. CEA allows for consistent production in such regions where only short, seasonal growth is possible. Moreover, it can offer a lower-carbon alternative to traditional farming by eliminating the need for traditional farm equipment and often significantly reducing transportation miles.
After several months, the container was deemed “operational” – meaning that all phases of the growing cycle were occurring simultaneously. During consistent operating conditions, the container used an average of 4,701 KWh per month, which broke down into 74% lighting, 21% HVAC, and 5% other. MRES notes that the horticulture lighting, which operated for 19 hours a day, could be shifted to allow the five hours of artificial night to coincide with a utility’s peak load.
This project sought to understand what impacts CEA might have on utilities’ loads as such agricultural practices becoming increasingly common or necessary. In its final report, though, MRES takes care to emphasize that the results also demonstrate the myriad benefits of these programs. Specifically, the report highlights the ability for CEA to serve as a platform through which utilities can continue to build relationships with their communities by repurposing abandoned buildings for agricultural projects, offering unique crops, and expanding educational affiliations or connections with community groups.
Over the course of the project, the container produced 1,751 pounds of lettuce, which was “inspected, cleaned, packaged, and distributed by the SDSU Food Science department” to sites across the local area. Beneficiaries of the produce included The Children’s Museum of South Dakota, the Boys and Girls Club, the Brookings Food Pantry, and the Brookings Domestic Abuse Shelter. The container produced an average of 56 pounds of lettuce for these organizations each week it was in production.
Put simply, the report posits that the project “demonstrated how electric technologies can be used in food production, reduce carbon emissions, provide educational opportunities, and provide crop diversity to the farming community,” in addition to ensuring that “greenhouse gas emissions from food production are centralized, are based on the generation source, and can be closely monitored.”
CEA comes with challenges, too, and the report notes that the initial investment can be prohibitive. The container used in this project was purchased for $250,000, with utility costs averaging $18.28 per day for electricity and 14 cents per day for water.
Another hurdle MRES highlights is technical expertise. As noted above, Freight Farms provided training for use of the container, and the project required an average of 30 hours of labor per week. MRES estimated the cost of this labor to be $66,565 for one year.
Furthermore, over the course of the research period, the container required maintenance and repairs totaling $43,200. Roughly half of those costs arose from repairs necessitated by extreme weather conditions when the container was not operational.
CEA nonetheless represents an area of great opportunity for electric utilities, opening up potential community partnerships and benefits ranging from learning opportunities and community engagement to increased access to fresh, high-quality produce.
Since the study’s completion, the CEA container has been moved to Woodbine, Iowa, where it is being used by a career and technical education center catering to high school students. The center, IGNITE Pathways, continues to leverage the container for learning opportunities and “a reliable supply of fresh local produce.”
MRES is a joint action agency made up of 61 member municipalities in Iowa, Minnesota, North Dakota, and South Dakota. MRES generation resources include hydropower, wind, nuclear, solar, coal, natural gas, fuel oil and market purchases. Brookings Municipal Utilities (BMU) was the member utility that provided electrical services to this project.
Founded in Palo Alto, Calif., in 1972, EPRI is an independent non-profit energy research, development, and deployment organization, with three specialized labs. EPRI also maintains an employee presence in more than a dozen countries in Europe/Middle East/Africa, as well as Asia, and the Americas through its subsidiary EPRI International Inc. and its Ireland-based research arm, EPRI Europe DAC.
APPA’s DEED program funds research, pilot projects, and education to improve the operations and services of public power utilities, with particular emphasis placed on the scalability and transferability of projects for other utilities. For more information on the DEED program, to become a DEED member, or to apply for a DEED grant, see the APPA website.
