Agrivoltaics

Nearly 30 years ago, we attended a sustainability-themed symposium. One of the sessions featured a presentation by academics from the local university who had been studying how much land area would be needed if North America were to have all its electricity supplied by wind and photovoltaic (PV) sources. The specific number they calculated is lost to our failing memory, but at the time it seemed shockingly large.

Given that much of the land in question was farmland, due to the unequal geographic distribution of suitable renewable resources, the academics concluded that renewables would never be a viable large scale alternative to fossil fuels.

The conclusion the academics reached rested on three assumptions. The first was the land required for large wind turbines was calculated by the diameter of the vertical swept area of the blades times a full horizontal circle, plus access roads. The second assumption was the land required for PV was calculated by the projected area of the panels plus their maintenance access roads. The third assumption was that using the land for renewables infrastructure excluded any other use.

Even at the time of the symposium, those assumptions were questionable. Wind-power utilities were already leasing land from farmers in an arrangement that proved beneficial to both. Since the actual footprint of the base of the turbine towers was small, the land taken out of production was minimal, while the lease payments to the farmers more than made up for any loss of agricultural income. This type of business arrangement has since become common in the United States, facilitating, in part, the growth of the installed wind generating capacity there from about five GW in 2002 to over 69 GW in 2015.¹

Notwithstanding the subsequent proliferation of wind power, the view that renewably-generated electricity infrastructure excludes other land uses was still prevalent among some researchers² as recently as 2017. While that may largely be true for hydroelectricity reservoirs and biomass, it no longer need be true for PV.

Now, electricity producers and farmers are cooperating to combine various forms of agricultural production with PV installations. The practise was documented as early as 1981,³ and is now known by various names: “agrophotovoltaics” in Germany, in India “solar sharing”, in China “PV agriculture”, and “agrivoltaics” in North America.⁴ A variety of types of agriculture fall under the agrivoltaic umbrella, but broadly speaking, most of the agricultural benefits accrue from the partial shade the PV panels provide, which lowers the temperature, retains moisture, increases yield and can provide pollinator habitat.⁵ However, agrivoltaics does not work well with crops where sunlight is a limiting growth factor.

For those plants that thrive in partial shade, the benefits to crop production from PV arrays are synergistic. While the panels reduce the sunlight on the crops below them, compared to open fields, they lower the air and ground temperature during the day and raise the temperature at night, thereby retaining more soil moisture and reducing the need for irrigation. The reduced temperature also cools the PV panels, which increases their efficiency, and therefore their electricity production. If the land under the arrays is used to graze livestock, the animals control vegetation, which reduces maintenance costs by eliminating herbicides and mowing. Grazing animals also benefit directly from the shade under the panels.⁶

The PV arrays also generate additional income for the farmers.
There may be further unexpected benefits to agrivoltaics. One example is Australian farmer Tony Inder, who grazes his 1700 Merino sheep under the panels of the 174 MW Wellington Solar Farm in New South Wales. Tony reports improved quality of the wool from his sheep.⁷ He says that the wool, when measured by growth, weight and fibre diameter, is about 20% superior to normal wool. He attributes the improvement to less variable soil moisture resulting from the panels, which makes for more consistent quality forage for the sheep.

A combined PV-plus-sheep project in Perry, Georgia, USA, provides another example of multiple benefits. It turns out that the hot, humid climate there is not ideal for sheep, who are vulnerable to the region’s parasites. Local farmer Roxanne Newton, who spent 20 years creating a heat- and parasite-resistant breed, has partnered with a solar development company in a 282 hectare, 68 MW tracking panel project.⁸

By rotational grazing, sheep do all the landscape work under the panels, so that in 2024, the only mowing that was required was at the edges. Sheep droppings fertilize the land under the panels, which not only eliminates chemical fertilizer, but enhances soil health through increased microbial activity, further increasing diversity and numbers of wild plants, insects and local wildlife.

Improved conditions for wildlife is not only anecdotal. A study of farmland in East Anglia, UK, found that mixed-habitat solar farms hosted up to three times the number of birds compared to high-yielding pure cropland nearby.⁹

How widespread is agrivoltaics and what are the most common agriculture practises involved? Getting a handle on the size of the phenomenon is difficult, hampered by several problems. Definitions of what exactly constitutes an agrivoltaic project are variable — should a greenhouse with some PV panels on it being considered an agrivoltaic installation? Do you measure the size of an agrivoltaic project by land area covered or by peak PV production capacity?

The land area of agrivoltaic projects varies widely — from farms about the size of a couple of North American suburban lots¹⁰ to projects covering about 2500 hectares.¹¹ Peak PV capacity of individual projects range from a few kilowatts to nearly a gigawatt(GW). In addition, there is no consistency in reporting among organizations tracking the industry - some do not distinguish between overall PV capacity in a region and agrivoltaics.

It might be more instructive to look at some individual regions.

In the United States, the National Renewable Energy Laboratory, in March 2023, identified 314 agrivoltaic projects there, with a total solar capacity of 2.8 GW of power. Most of these projects integrated PV and grazing, with relatively few growing crops directly.¹² The American Solar Grazing Association puts the number of PV grazing operations at over 500 as of 2025.¹³ The US Department of Agriculture estimates that only about 5% of agrivoltaic projects consist of crops (mostly fruits and vegetables) grown directly under PV arrays.¹⁴ The department also suggests that what is grown under the rest are grasses and native vegetation, presumably for grazing animals.

In India, a 2023 study¹⁵ of the state of agrophotovoltaics found 22 operational projects, with more planned. They are comprised of R&D pilots, direct government-supported projects, and commercial projects. Most of the projects, unlike in North America where grazing predominates, combine PV with crops, growing vegetables, herbs, fruit, flowers, and cotton. One small project in Rajasthan combines PV with fish farming.

Definitive government numbers for Europe are hard to come by, but SolarPower Europe launched a digital map in 2024 showing about 200 installations.¹⁶ About a quarter of them are in France. From a PV capacity perspective, most are under 20 MW with only about 10% larger, and none are larger than 100 MW.

China currently has over 500 documented¹⁷ agrivoltaic projects. In addition to grazing and crop production, installations include tea plantations and shrimp-farming ponds. PV for the latter provides power to run the operation and the shade cools the water, increasing shrimp productivity.

Japan had 3,474 agrivoltaic projects as of 2023,¹⁸ but most were very small scale, being on farms of less than 0.1 Ha.[19]

What of the future? Agrivoltaics seems to have a lot of promise because it addresses both the growing need for food production and energy in one solution. Growth rates are impossible to predict at this point.

The agrivoltaics industry faces a number of challenges to growth. The challenges are many and varied, with the detail beyond the scope of this article, but there are broad categories[20]:

• Lack of standardised definitions that lead to confusion in tracking, reporting, and regulating for policy makers and investors.
• Lack of policy and/or restrictive regulations, including zoning of land use and energy production separately.
• Uncertainty among investors, due to the field’s relative immaturity, around capital costs and rates of return.
• Evolving technology obscures which combination of PV types and agriculture is optimum for any specific situation.

One small example illustrates both the opportunity for the industry and the difficulty of keeping up with changing technology in the field. A company in Europe recently introduced a new, bi-facial (active PV on both sides of the panel), translucent PV module, specifically designed for agrivoltaics. Each module measures about 1 m by 2 m, has a peak output of 320 W (our rough calculation puts its efficiency at about 16%), and is 45% transparent, significantly higher than most previous designs.[21]

Perhaps industry-specific innovations, like these panels, will accelerate the nascent agrivoltaics industry.

Reading

1. https://www.usda.gov/sites/default/files/documents/FINAL-Wind_Energy_Land_Distribution_in_the_United_States_of_America_7282017.pdf.
2. Iñigo Capellán-Pérez, C. Castro and I. Arto. "Assessing vulnerabilities and limits in the transition to renewable energies: Land requirements under 100% solar energy scenarios." Renewable & Sustainable Energy Reviews, 77 (2017): 760-782. https://doi.org/10.1016/J.RSER.2017.03.137.
3. GOETZBERGER, A., and A. and ZASTROW. “On the Coexistence of Solar-Energy Conversion and Plant Cultivation.” International Journal of Solar Energy 1, no. 1 (January 1, 1982): 55–69. https://doi.org/10.1080/01425918208909875.
4. Mamun, Mohammad Abdullah Al, Paul Dargusch, David Wadley, Noor Azwa Zulkarnain, and Ammar Abdul Aziz. “A Review of Research on Agrivoltaic Systems.” Renewable and Sustainable Energy Reviews 161 (June 1, 2022): 112351. https://doi.org/10.1016/j.rser.2022.112351.
5. “(PDF) Agrivoltaics Provide Mutual Benefits across the Food–Energy–Water Nexus in Drylands.” ResearchGate, December 9, 2024. https://doi.org/10.1038/s41893-019-0364-5.
6. “Agrivoltaics.” Accessed April 2, 2025. https://www.nrel.gov/solar/market-research-analysis/agrivoltaics.html.
7. Hunter, Pamela. “Study Shows Sheep Grazing under Solar Panels Produces Higher-Quality Wool.” pv magazine International, November 6, 2024. https://www.pv-magazine.com/2024/11/06/study-shows-sheep-grazing-under-solar-panels-produces-higher-quality-wool/.
8. Ludt, Billy. “Permanent Sheep Flock Leaves Georgia Solar Project’s Land Healthier than before.” Solar Power World, February 20, 2025. https://www.solarpowerworldonline.com/2025/02/permanent-sheep-flock-leaves-georgia-solar-projects-land-healthier-than-before/.
9. Waite, Catherine, and Joshua Copping. “Solar Farms Can Host up to Three Times as Many Birds as Crop Fields – New Research.” The Conversation, March 4, 2025. http://theconversation.com/solar-farms-can-host-up-to-three-times-as-many-birds-as-crop-fields-new-research-249551.
10. Tajima, Makoto, and Tetsunari Iida. “Evolution of Agrivoltaic Farms in Japan.” AIP Conference Proceedings 2361, no. 1 (June 28, 2021): 030002. https://doi.org/10.1063/5.0054674.
11. Lewis, Michelle. “Ohio’s Largest Solar Farm Will Also Be the US’s Largest Agrivoltaics Project.” Electrek, March 25, 2024. https://electrek.co/2024/03/25/ohios-largest-solar-farm-us-largest-agrivoltaics-project/.
12. Agrivoltaics, NREL, op cit.
13. “Solar Grazing Census - American Solar Grazing Association,” August 18, 2024. https://solargrazing.org/census/.
14. “Common Ground for Agriculture and Solar Energy: Federal Funding Supports Research and Development in Agrivoltaics | Economic Research Service.” Accessed April 2, 2025. https://www.ers.usda.gov/amber-waves/2024/april/common-ground-for-agriculture-and-solar-energy-federal-funding-supports-research-and-development-in-agrivoltaics.
15. Pulipaka ,Subrahmanyam; Peparthy, Murali; Vorast, Maximilian; Y.V.K., Rahul, National Solar Energy Federation of India, July 2023, https://indiaagripv.org/assets/publications/NSEFI_on_AgriPV_in_India.pdf.
16. “New Agrisolar Digital Map Presents over 200 Projects across Europe - SolarPower Europe.” Accessed April 3, 2025. https://www.solarpowereurope.org/press-releases/new-agrisolar-digital-map-presents-over-200-projects-across-europe.
17. Silan, Jose Gabriel, Shengnian Xu, and Marlon Joseph Apanada. “Dual Harvest: Agrivoltaics Boost Food and Energy Production in Asia,” May 23, 2024. https://www.wri.org/insights/agrivoltaics-energy-food-production-asia.
18. Shulman Advisory. “Overview of the Agrivoltaic Industry in Japan,” September 20, 2022. https://shulman-advisory.com/overview-of-the-agrivoltaic-industry-in-japan/.
19. Tajima, et al, op cit.
20. “Overcoming Challenges in AgriVoltaics: From Policy Barriers to Technological Innovation.” Accessed April 3, 2025. https://www.leadventgrp.com/blog/overcoming-challenges-in-agrivoltaics-from-policy-barriers-to-technological-innovation-1.
21. pv magazine International. “Grid Parity Unveils New Glass-Glass Module for Agrivoltaic Systems,” March 4, 2025. https://www.pv-magazine.com/2025/03/04/grid-parity-unveils-new-glass-glass-module-for-agrivoltaic-systems/.