Tag Archive for: Agrivoltaics

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Agrivoltaic Engineering and Layout Optimization Approaches
in the Transition to Renewable Energy Technologies: A Review

This resource shows that agrivoltaics have the potential to benefit both crop yield and photovoltaic efficiencies. Innovative engineering technologies related to photovoltaic tracking along with new generation photovoltaic cells were reviewed to determine the factors that influence optimization in agrivoltaic systems. The review also investigates the last five years of research in agrivoltaic optimization and implications of future AV developments.

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AgriSolar News Roundup: Vermont Agrisolar Study, Agrisolar Research in Maine, Wisconsin Dairy Farm Goes Agrisolar 

Vermont Agrisolar Study Shows that Saffron Grows Well Under Solar Panels 

“A study released earlier this year summarized the results of a three-year experiment conducted by the University of Vermont. The research concluded that, given the right soil conditions, saffron grows well in the aisles and at the edges of a solar array, which could boost bottom lines for farmers by allowing them to draw dual revenue streams from a single section of land. 

‘We could see diversified vegetable growers growing lots of spinach and kale, but they weren’t making any money at it because everybody was growing the same thing. We felt saffron offered an opportunity for these growers to add a high-value crop,’ said Margaret Skinner, a researcher at the University of Vermont.  

According to the study, “when soil conditions are suitable, saffron can be grown successfully within a conventional tilted solar array, generating between $7,500 – 130,000 per acre.” – Energy News Network 

University of Maine Studies Agrisolar Blueberry Yield  

“A farmer in Maine has teamed up with a solar developer and university researchers to find out how his (blue)berries fare when partially shaded by solar panels. The University of Maine is studying this example of dual-use agrivoltaics.  

The solar installation was developed by the Boston-based solar developer BlueWave, and it is owned by the company Navisun, which makes lease payments to the landowner. Sweetland tends, harvests, and sells the blueberries, and shares profits with the landowner. 

The university (Maine) received grant funding to continue the study for three more years from the Northeast Sustainable Agriculture Research Education program, which is supported by the U.S. Department of Agriculture’s National Institute of Food and Agriculture. The research team will compare the blueberry yield among the plants fully shaded by panels, plants partially shaded by panels and plants with full sun. The panels are 8 feet tall in rows spaced 8 feet apart.” – Canary Media 

 Wisconsin Dairy Farmer Finds Financial Safety in Agrisolar  

“Brent Sinkula, president of the Manitowoc County Farm Bureau, understands the challenges Wisconsin dairies are facing. The changing dairy market has made it more difficult for small and mid-sized farms to continue. Without plans to expand the dairy, Sinkula was looking for another way to maintain the family farm. In 2018, an energy company approached him interested in renting 500 acres, about a third of his land, to install solar energy panels.  

For Sinkula, hosting solar panels on his land provides a financial safety net for the farm. He’s not the only farmer to make similar arrangements. Farmers have what solar energy companies need: land. Across the state, partnerships between dairy farms and energy companies are increasing, changing the landscape and providing farmers extra revenue in a sometimes unpredictable market.” – WPR 

AgriSolar News Roundup: Solar Sheep, Five C’s of Agrivoltaics, Illinois Team Developing AgriSolar Game  

The Solar Industry’s Mower of Choice: Sheep 

“The panels blanket nearly 1,500 acres of a solar farm in Deport, a town near the Oklahoma border. Ely Valdez, the boss, makes sure prairie grasses don’t block sunshine from the panels. His sheep do most of the work. Sheep, the surprise workhorse of renewable energy, are generating several million dollars in annual revenue tidying up solar farms nationwide. 

‘It’s changing all of our lives,’ said Mr. Valdez. He expects the flocks he oversees to soon generate several hundred thousand dollars in annual revenue. The number of acres of solar fields employing sheep in the U.S. has grown to tens of thousands from 5,000 in 2018, according to estimates by people in the business. Flock owners charge as much as $500 an acre a year. 

The solar industry auditioned several methods for the job, but requirements weeded out expected contenders. Power mowers, which can’t maneuver easily enough under panels to avoid the risk of damaging equipment, are of limited use. “Sheep truly are the appropriate technology for this,” said Michael Baute, vice president of regenerative energy and carbon removal at solar developer Silicon Ranch Corp., based in Nashville, Tenn.” – The Wall Street Journal 

The “Five C’s” of Agrivoltaics 

“These are among the most important findings of an ongoing agrivoltaics research project called Innovative Solar Practices Integrated with Rural Economies and Ecosystems (InSPIRE). Led by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy’s Solar Energy Technologies Office, InSPIRE has just completed its second, three-year phase of research into the synergies between solar energy and agriculture.  

In its first phase, InSPIRE tried to quantify the benefits of agrivoltaics and record some early best practices in the emerging field. The project adopts a big-tent approach to agrivoltaics, welcoming any dual use of solar-occupied land that provides ecological or agricultural benefits. That could mean grazing cattle or sheep, growing crops, cultivating pollinator-friendly native plants, or providing ecosystem services and restoring degraded soil.  

The InSPIRE project found five central elements that lead to agrivoltaics success, summarized as ‘the five C’s’: 

  • Climate, Soil, and Environmental Conditions — The ambient conditions of a location must be appropriate for both solar generation and the desired crops or ground cover.  
  • Configurations, Solar Technologies, and Designs — The choice of solar technology, the site layout, and other infrastructure can affect everything from how much light reaches the solar panels to whether a tractor, if needed, can drive under the panels. “This infrastructure will be in the ground for the next 25 years, so you need to get it right for your planned use. It will determine whether the project succeeds,” said James McCall, an NREL researcher working on InSPIRE.  
  • Crop Selection and Cultivation Methods, Seed and Vegetation Designs, and Management Approaches— Agrivoltaic projects should select crops or ground covers that will thrive under panels in their local climate and that are profitable in local markets.  
  • Compatibility and Flexibility — Agrivoltaics should be designed to accommodate the competing needs of solar owners, solar operators, and farmers or landowners to allow for efficient agricultural activities.  
  • Collaboration and Partnerships — For any project to succeed, communication and understanding between groups is crucial.” –  NREL 
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Illinois University Team Developing Interactive Agrisolar Game  

“A team led by University of Illinois, Urbana-Champaign researchers is developing an educational game it hopes can inspire future farmers to think differently about solar power. The app aims to teach kids the emerging concept of agrivoltaics, in which agricultural production is combined with solar photovoltaics. The game will be backed by science from the growing niche of research looking into how solar panel placement affects the growth of various crops.  

‘Dual-use land is really a great idea, intuitively, so why not build an app that lets kids explore these really interesting ideas while they’re playing a game?’ said H. Chad Lane, associate chair for educational psychology at the University of Illinois, Urbana-Champaign. 

Think Farmville, but instead of gamifying every aspect of running a farm, it will focus on the interaction between crops and solar panels. Researchers are discovering that several plant types can perform better when partially shaded by panels; for others, the reduced production can be offset by extra revenue from selling solar power to the electric grid.” – Energy News Network 

Community AgriSolar: Merging Agrisolar and Community Solar 

Merging community solar and agrisolar could aid the Department of Energy’s (DOE) goal of saving $1 billion in energy costs through community solar by 2025. Not only would merging community solar and agrisolar help DOE reach that goal, but would also provide other opportunities and benefits such as the regeneration of soil on solar sites, reducing fuel-operated maintenance demands, and increasing the likelihood of future solar development(s). 

What is community solar? 

Community solar could be an ideal method for low-income households who might be looking to use solar energy and use Low-Income Home Energy Assistance Program (LIHEAP) assistance to pay for their energy bills. LIHEAP funds cannot be used for things like up-front installation costs of typical solar participation methods (non-community solar) or the household ultimately owning the solar equipment. Community solar participation eliminates these issues due to the solar farm and panels not being developed, owned or operated by the LIHEAP recipient.  

LIHEAP Participants Would Lead to More Energy Savings 

Community solar often includes what is known as subscription-based community solar programs (SBCSPs), where a household “rents” solar panels and uses solar energy without the associated conditions and costs of installing solar panels, operating them, or owning them. These conditions of using solar energy typically would not qualify a low-income household to use LIHEAP funds for solar fuel. However, SBCSPs could provide a way for low-income households to be able to use LIHEAP benefit payments for solar fuel through subscription-based community solar programs because the household would not ultimately own the equipment or have to pay for its installation or maintenance costs. 

If LIHEAP participants are eligible for SBCSPs, then more people can participate in saving energy by using community agrisolar, which ultimately assists in the identified goal of the Department of Energy (DOE) in reaching $1 billion in energy savings through community solar by 2025. 

Why merge agrisolar with community solar? 

Community solar has been identified by DOE as a method of reaching energy savings goals by 2025, which includes saving $1 billion in energy costs. Merging agrisolar with community solar developments would not only aid in significant energy savings but would also make future solar developments more likely to be approved—expanding energy savings even further. 

Agrisolar operations like the Cabriejo Ranch in Missouri has shown that agrisolar provides a variety of energy saving methods as well as regenerating the land used by solar farms. The ranch uses Dorper sheep to manage the vegetation on solar operations, which drastically reduces the use of fuel-operated maintenance equipment typically used to manage vegetation. The sheep not only reduce these energy costs, but dramatically increase the health of the soil .  

The likelihood of a solar farm being approved for development is higher when Agrisolar is incorporated into the operations. This was seen in the Garnet Mesa project that was denied due to concerns about losing valuable farmland to the solar-farm development. The project was approved after changes were made to include 1,000 grazing sheep on the solar farm. 

The Possibilities of Merging Agrisolar and Community Solar   

 More participants saving more energy would be a win-win for reaching energy-and-cost savings goals.  

Not only do energy savings goals have a higher likelihood of being achieved through merging community solar and agrisolar, but other benefits of using agrisolar would also be made possible, such as regenerating soil health through grazing practices and supporting  job creations in local communities such as grazing management and farm operations jobs created in Missouri. These benefits of using agrisolar in solar development increases the likelihood of future solar developments by proving the land can be effectively utilized while occupied by solar equipment and operations.  

Follow the Sun Tour: Massachusetts

By Stacie Peterson, PhD

See more photos from the tour in the AgriSolar Flickr album here: Follow the Sun Tour: Massachusetts | Flickr

The farmlands of Massachusetts are cherished landscapes, steeped in cultural significance and family connections. Coming from the drought-ridden western United States, I was struck first by the lack of irrigation pivots and the lushness of the landscape, even after a heatwave uncommon to the area. I then scanned the rolling hills for solar, excited to see the Massachusetts SMART program in action. I wasn’t disappointed. The solar array at the University of Massachusetts South Deerfield Research Farm presented a picture-perfect site to start our tour.

Follow the Sun Tour Attendees at the UMass South Deerfield Agrivoltaic Research Site

The tour attendees matched my enthusiasm by showing up early and leaning over the fence to better view the solar farm. We were welcomed by Dr. Dwayne Berger from University of Massachusetts, who gave a presentation on the DOE SETO-funded research at the farm. This project involves the study of crop productivity on crops planted under a solar array installed by Hyperion Solar.

Next, Gerry Palano gave a presentation on Massachusetts Agricultural Solar Tariff Generation Units and their relation to agrivoltaics in the Massachusetts Solar Massachusetts Renewable Target (SMART) Program, which provides financial incentives for solar projects. From there, we went out to the farm, where Jake Marley from Hyperion Systems described the solar array design, and Dr. Stephen Herbert discussed the current crops and research at the array.After a quick lunch, we boarded the bus and started our mobile conference of speakers. Dr. Zach Goff-Eldredge kicked off the bus tour with a discussion of DOE SETO’s programs and their support of agrivoltaics. 

Dr. Zach Goff-Eldredge Manager of DOE SETO Agrivoltaic Programs

AgriSolar Clearinghouse consultant Alexis Pascaris of AgriSolar Consulting then gave an inspiring talk, envisioning the future of agrisolar from the perspective of farmers, landowners, solar developers, and community members.    

Candace Rossi from the New York State Energy Research and Development Authority (NYSERDA) then spoke to the group about the impactful programs in New York State and their relevance to AgriSolar around the country. We arrived at Nate Tassinari’s family farm in Monson with the sun high overhead. Nate welcomed the group to his home and talked about the Million Little Sunbeams project he developed  to preserve his family’s farmlands. The farm includes co-located solar and hay, an apiary, and an orchard. As shown in the photo, the 250-kW solar array, installed by Sunbug Solar, has an elevated racking system that accommodates haying equipment. The panels are bifacial, and Nate described the increased solar energy production from the bifacial panels as a result of both hay and snow reflections.

The Million Little Sunbeams project created a financial pathway for Nate and his family to own the land and the solar system; this project does not involve a lease to a solar developer.  Nate graciously fielded questions about his process and Gerry Palano fielded questions about the SMART funding piece of the project. Nick d’Arbeloff from Sunbug Solar fielded technical questions about the solar array and site design.

Nate Tassinari at Million Little Sunbeams Solar and Hay Site

We then travelled to a late-breaking and welcome addition to our tour with Dan Finnegan from Solar Shepherd in Brookfield. On the way, Lexie Hain, former president of the American Solar Grazing Association and current Director of Agrivoltaics and Land Management at Lightsource BP, gave the group a background on solar grazing.When we arrived at Solar Shepherd, Dan’s assistant, Reggie the Wonder Dog, herded the sheep toward the gate to greet us and then herded them to the solar array, so we could witness solar grazing first- hand. Dan described his solar grazing work in Massachusetts and talked with tour members about the practicalities of solar grazing, such as sheep transportation, water needs, leasing, and solar grazing contracts.

Solar Grazing with Solar Shepherd

After Solar Shepherd, we boarded the bus to travel to our last agrisolar site: Grafton Solar at Knowlton Farms. On the way, we heard from AgriSolar Clearinghouse stakeholder Ethan Winter from American Farmland Trust (AFT) about AFT work on smart solar siting, agrivoltaics, and at  

Grafton Solar at Knowlton Farms provided the tour group with the opportunity to see a large-scale agrisolar site. The 334-acre hay farm includes solar developed in several phases on 75 acres. In addition to Paul Knowlton, fourth-generation family owner of Knowlton Farms, the project includes a slew of agrivoltaic advocates, solar developers, researchers, and the State of Massachusetts. 

The agrisolar portion of Knowlton Farms, known as Grafton Solar, is owned and operated by AES Corporation, which pays Knowlton Farms lease payments and a stipend for the cost of farming. The Massachusetts SMART program provided incentives for the project and the University of Massachusetts and American Farmland Trust study the impact of the solar array on crop yields and soil conditions.

Paul Knowlton, at Grafton Solar at Knowlton Farms

Paul Knowlton talked with the group about his decision to enter into a lease agreement for solar at his farm, its positive financial impact to his family business, and his hopes that the project will help keep the farm in the family well into the future. Dr. Sam Glaze-Corcoran from University of Massachusetts Amherst described soil and crop studies and, along with Gerry Palano and Swayne Berger, fielded questions about how those studies inform University of Massachusetts recommendations to the SMART program.  Ian Ward, of Solar Agricultural Services, discussed the site design, plantings, and the potential for this project to serve as an example for other farmers in New England. Ian’s advocacy centers on keeping farmlands in the hands of farmers and in preserving farmlands for the future. Julie Fine, AFT’s Climate and agriculture specialist then led the group crop co-location potion of the site and described her work assessing impacts to crops, soil, and ecosystem services.

The group then boarded the bus for the ride back to Amherst, full of ideas, connections, and energy. Charles Gould, from Michigan State University Extension, talked about his impressions of the day, his work in agrivoltaics, and his thoughts on the future. Judy Anderson, of Community Consultants, led the tour group in a roundtable discussion of the tour, ways to engage policy makers, and how to move forward in a way that supports agrisolar throughout the country. 

Million Little Sunbeams AgriSolar Site

Tours like this are months in the making. From scouting potential sites and tour routes to meetings with farms, solar developers, local governments, and potential speakers. They have the complexity and logistics of a mobile conference. This tour couldn’t have happened without the help of Alexis Pascaris of AgriSolar Consulting and Jake Marley of Hyperion Systems. They were at the heart of this tour and worked with me for months as we planned, connected, and revised. They were flexible with last-minute changes, and I deeply appreciate their contributions to the tour.

I’d like to thank University of Massachusetts for hosting the event at the South Deerfield farm and for allowing us to gather in their meeting space. Thank you, too, to Nate Tassinari for hosting us at his home in Monson; I appreciate his flexibility with last-minute schedule changes and his warm and insightful tour of his farm. Dan Finnegan and Reggie the Wonder Dog deserve a huge round of applause for treating the group to a demonstration of solar grazing in Brookfield. And thank you to Paul Knowlton, The AES Corporation, Ian Ward, Glaze-Corcoran, Julie Fine, Dwayne Berger, and Gerry Palano for the excellent tour of Knowlton Farms. It is a model agrisolar site with impressive research and support.

I’d like to thank the Solar Energy Technology Office of the U.S. Department of Energy for funding this work and Dr. Zach Goff-Eldredge for attending the tour. His support of agrivoltaics is evident around the country and the work the SETO team is doing in this space is creating a pathway for co-located agriculture and solar that works for farmers, community members, and solar developers.

NCAT’s Sustainable Energy and Sustainable Agriculture Teams Joining Forces for AgriSolar

I’d like to thank Danielle Miska, Andy Pressman, and Chris Lent from NCAT for their work on this project and for the AgriSolar Clearinghouse team at NCAT, around the country who cheered us on. I’d also like to thank Nicole Karr, our photographer. It is her beautiful photos throughout this blog. Finally, I’d like to express my gratitude to the tour attendees. The Follow the Sun Tour is one way the AgriSolar Clearinghouse works to build community, relationships, and trusted, practical information and I thank you all for joining us. It was a marathon tour of presentations, site tours, bus speakers, roundtables, networking, honey sticks, and fun. Your energy and enthusiasm are inspiring, and I can’t wait to see you on the road again.

See more photos from the tour in the AgriSolar Flickr album here: Follow the Sun Tour: Massachusetts | Flickr.

AgriSolar News Roundup: Colorado Solar Grazing, Delaware Agrisolar, Plattsburgh Solar Grazing 

1,000 Sheep Will Graze Colorado Solar Farm  

“Solar developer Guzman Energy achieved regulatory approval from the Delta County Board of Commissioners for a limited use permit to install and operate an 80 MW project on land in Southern Delta County, Colorado. The site that will house the array is currently irrigated and utilized for grazing, and will continue to be used in that manner, said Guzman Energy. About 1,000 sheep will remain on the site to manage vegetation and graze on native plants.” – PV Magazine 

Delaware Solar Farm Grows Perennials  

“There’s nothing particularly remarkable about a farm growing common decorative flowers, but the Remelts aren’t growing them in the traditional way, which would be in a greenhouse or outdoors at a nursery. Instead, they’re raising mums in a row between two banks of solar panels—making agricultural use of idle land that so many farmers who have reserved acreage for lucrative solar farms might have written off as unusable. 

Parker explained how he and his father, when considering how to use the land occupied by the solar panels, settled on planting mums. They needed a crop that wouldn’t interfere with the operation of the panels, a qualification the mums met. As a bonus, the perennial flower also tends to be hardier when grown outdoors.” – Rochester City Newspaper 

Sheep Grazing New Solar Farm in New York 

“The solar array sits on 23 acres with a strict grass height limit. ‘The main goal here is we don’t want the grass or any vegetation growing above the panels blocking sunlight, basically a loss of power,’ said the farm’s Josh Pierce. He says it would take a lot of effort to cut and trim all that vegetation. ‘Underneath the panels— the grass also grows up there— that’s the challenge of getting a mower in.’ 

Their 75 sheep live at the solar farm from May until October. Their job is to graze the grass and weeds to make sure the solar panels are clear to soak in the sun. ‘A lot of this is great forage. It’s a mix of orchard grass and alfalfa, which is like candy for them,’ Josh explained.” – WCAX 

Solar Farm Gets Green Light After Including Agrisolar

Delta County, Colorado, commissioners have given approval to the Garnet Mesa solar farm to proceed with developing a 475-acre, 80-megawatt solar farming facility that was previously rejected due to concerns about losing farmland. After developers modified their plan by added 1,000 sheep to occupy the farm, commissioners voted to grant the land-use permit, satisfied that concerns about losing farmland had been resolved due to the conversion to agrisolar.  

“All negative comments were addressed by the applicant except for use of other desert lands for a solar energy facility. Those in favor of bringing a solar energy system to Delta mentioned helping the environment, additional tax revenue for the city, cheaper rates for customers and having a local energy source as reasons to support the proposal,” according to the Delta County Independent. 

“Interior fencing will be added to facilitate safe containment for the sheep and to prevent overgrazing. Sheep will also be provided with watering sites and other facilities necessary for safety and well-being, according to project plans presented during an open house,” said the article. 

“The two commissioners opposing the plan said they were concerned about the loss of agricultural land in the county. Guzman Energy has revised its Garnet Mesa project to ‘specifically address the agricultural and irrigation concerns raised by the community and commissioners,’ Amy Messenger, a company spokeswoman, said in an email,” according to The Colorado Sun.  

Garnet Mesa is expected to produce enough power for 18,000 homes each year and to create an estimated 350 to 400 employment opportunities, including sheep and farm management. 

New Reports Highlight Best Practices of Combining Solar Energy and Agriculture

Two new reports funded by the U.S. Department of Energy Solar Energy Technologies Office highlight the potential for successfully and synergistically combining agriculture and solar photovoltaics technologies on the same land, a practice known as agrivoltaics. One report details the five central elements that lead to agrivoltaic success, while the other addresses emerging questions for researchers related to scaling up agrivoltaic deployment, identifying barriers, and supporting improved decision-making about agrivoltaic investments. Learn more about the reports’ findings.

The first report, The 5 Cs of Agrivoltaic Success Factors in the United States: Lessons From the InSPIRE Research Study, examines the Innovative Solar Practices Integrated with Rural Economies and Ecosystems (InSPIRE) project, which was funded by the U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) starting in 2015. Over the past seven years, the project’s multiple phases have studied the co-location of solar with crops, grazing cattle or sheep, and/or pollinator-friendly native plants, and the resulting ecological and agricultural benefits.

According to InSPIRE research, there are five central elements that lead to agrivoltaic success:

  • Climate, Soil, and Environmental Conditions – The location must be appropriate for both solar generation and the desired crops or ground cover. Generally, land that is suitable for solar is suitable for agriculture, as long as the soil can sustain growth.
  • Configurations, Technologies, and Designs – The choice of solar technology, the site layout, and other infrastructure can affect everything from how much light reaches the solar panels to whether a tractor, if needed, can drive under the panels.
  • Crop Selection and Cultivation Methods, Seed and Vegetation Designs, and Management Approaches – Agrivoltaic projects should select crops or ground covers that will thrive in the local climate and under solar panels, and that are profitable in local markets.
  • Compatibility and Flexibility – Agrivoltaics should be designed to accommodate the competing needs of solar owners, solar operators, and farmers or landowners to allow for efficient agricultural activities.
  • Collaboration and Partnerships – For any project to succeed, communication and understanding between groups is crucial.

The 5 Cs of Agrivoltaic Success Factors in the United States: Lessons From the InSPIRE Research Study

This report examines the NREL Innovative Solar Practices Integrated with Rural Economies and Ecosystems (InSPIRE) project, which was funded by the U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) starting in 2015. Over the past seven years, the project’s multiple phases have studied the colocation of solar with crops, grazing cattle or sheep, and/or pollinator-friendly native plants, and the resulting ecological and agricultural benefits.

According to InSPIRE research, there are five central elements that lead to agrivoltaic success:

  • Climate, Soil, and Environmental Conditions – The location must be appropriate for both solar generation and the desired crops or ground cover. Generally, land that is suitable for solar is suitable for agriculture, as long as the soil can sustain growth.
  • Configurations, Technologies, and Designs – The choice of solar technology, the site layout, and other infrastructure can affect everything from how much light reaches the solar panels to whether a tractor, if needed, can drive under the panels.
  • Crop Selection and Cultivation Methods, Seed and Vegetation Designs, and Management Approaches – Agrivoltaic projects should select crops or ground covers that will thrive in the local climate and under solar panels, and that are profitable in local markets.
  • Compatibility and Flexibility – Agrivoltaics should be designed to accommodate the competing needs of solar owners, solar operators, and farmers or landowners to allow for efficient agricultural activities.
  • Collaboration and Partnerships – For any project to succeed, communication and understanding between groups is crucial.

Successes and failures of prior agrivoltaic projects will inform new innovations as agrivoltaic projects continue to be deployed globally. This report represents a synthesis of lessons learned from agrivoltaic research field sites located across the United States as part of the InSPIRE project. The projects considered represent a diverse mix of geographies, agrivoltaic activities, and technology configurations. In this report, we have provided a list of features that contribute to the success of agrivoltaic installations and research projects, with partnerships playing a crucial role in both. The researchers suggest future research activities that align with these core principles as well as other approaches to grow agrivoltaic research efforts globally.

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Case Study: Jack’s Solar Garden

An aerial view of Jack’s Solar Garden

Jack’s Solar Garden is a  community solar garden in Boulder County, Colorado. With its 1.2-MW, single-axis tracking solar system, it is the largest commercial agrivoltaics research site in the United States. Covering over four acres of land on a 24-acre farm, Jack’s Solar Garden enables researchers from the National Renewable Energy Laboratory (NREL), Colorado State University (CSU), and the University of Arizona (UA) to study the microclimates created by its solar panels and how they impact vegetation growth. Additional partners include the Audubon Rockies, which planted over 3,000 perennials around the perimeter of the solar array, Sprout City Farms (SCF), the main cultivator of crops beneath the solar panels, and the Colorado Agrivoltaic Learning Center (CALC), which provides on-site educational opportunities for community groups to learn more about agrivoltaics. Jack’s Solar Garden also offers an annual stipend to an Artist on the Farm to engage the community on-site through their preferred art form. 

Electricity generated by Jack’s Solar Garden — enough to power about 300 average homes in Colorado annually — is sold to various subscribers via Xcel Energy’s Solar*Rewards Community program, where subscribers recieve a percentage of the net metered production as credits against their monthly electricity bills. Over 50 residents, five commercial entities (Terrapin Care Station, In The Flow: Boutique Cannabis, Western Disposal, Premiera Members Credit Union, and Meati), and two local governments (Boulder County and the City of Boulder) subscribe to Jack’s Solar Garden to support local, clean energy production, along with all the social and environmental benefits this development provides. Jack’s Solar Garden also donates 2% of its power production to low-income households through the Boulder County Housing Authority.  

Byron Kominek tilling under the panels at Jack’s Solar Garden

The solar array is designed to optimize electricity production while enabling researchers and agricultural workers to operate within the system. Torque tubes were elevated to 6-6.5 feet and 8 feet for two-thirds and one-third of the property, respectively, allowing researchers to study the difference these heights have on the microclimates and growing conditions of various crops within the solar array. During construction, land disturbance was minimized, leaving the long-standing brome and alfalfa forage relatively unharmed. Further, metal mesh was attached beneath the solar panels to help protect people within the solar array from electrical wires. 

Lettuce, Clary Sage, Grassland, and Raspberries all grown under the panels at Jack’s Solar Garden

Research at Jack’s Solar Garden includes: 

  • Crop Production and Irrigation Study to determine crop yields at different locations within the solar array with varying amounts of sunlight, shade, and allotted irrigation. 
  • Pollinator Habitat Research to measure the growth and performance of pollinator habitat seed mixes and evaluate different cost-effective vegetation-establishment techniques. 
  • Pasture Grass Research measuring the growth and performance of dryland pasture grass seed mixes with different cost-effective seeding methods. 
  • Grassland Ecology & Physiology Research seeking to understand the health and functions of grassland ecosystems within a solar array by studying light patterns, soil moisture retention, plant production and physiology, forage quality, and grassland resilience. 
  • Ecosystem Services Research evaluating multiple ecosystem services, such as carbon sequestration, erosion control, pollinator habitat, weed suppression, and microclimate moderation, provided by native vegetation and introduced pasture species within a solar array. 

These research projects were made possible through the dedication of the Kominek family, owners of Jack’s Solar Garden, to improve the economics of their hay farm while benefiting their local community. Local and State regulations supported the Kominek family’s ability to build Jack’s Solar Garden, including:  Colorado State legislation allowing for locally owned and interconnected community solar gardens as well as a Renewable Portfolio Standard that enables locally owned community solar gardens to generate 1.5x RECs per MWh; City of Boulder and Boulder County building codes requiring net zero for new homes  over 5,000 sq. Ft. and energy conservation codes that require either cannabis grow houses to pay taxes on energy consumed or to subscribe to local community solar gardens; and Boulder County’s Land Use Code update that provides solar array construction on prime farmland with a special land-use review process.