Canada’s pastures and cropland are prime sites for the mass deployment of solar energy infrastructure, according to advocates of agrivoltaics – a term used to describe the simultaneous use of land for solar energy and food production.
The use of solar panels on buildings, in pastures and in other areas of working farms is not new. Solar farms tightly pack panels together in some fields in the province, and solar trackers move their face to follow the sun in farmyards and on the edges of fields.
Why it matters: Earlier solar technology replaced the growing of crops on farmland. A new generation aims to mix both and improve farmland productivity.
What sets the concept of agrivoltaics apart is the scale at which solar energy can be harvested, and how doing so can increase farm productivity.
The high cost of solar infrastructure has been a limiting factor to more widespread use among landowners. Some think the right policies, and the right solar structure designs, could allow farmers to generate significant amounts of green energy while improving crop yields.
That’s the theory, anyway, and one that proponents hope to test in Ontario next summer.
According to Joshua Pearce, an engineer and chair of Information Technology and Innovation at Western University’s Ivey Business School, the idea behind agrivoltaic systems is to first generate green power for the farm and then for the wider grid, while simultaneously using the solar infrastructure to improve crop production.
Pearce cites three construction styles as options: a general one where horizontal panels sit just above the production area, the “French” design where panels are clustered to specific areas and higher off the ground, and vertical, fence-like modules.
He says the third design style is likely the best fit for many Ontario fields because the panel racks would be cheaper and the design would be less of a hindrance to machinery operations.
He says such systems are used in parts of Europe, Asia and Arizona. But in Canada, agrivoltaics have been held back by lack of investment, less-than-ideal energy policies and few practical examples of how large-scale solar energy infrastructure can work in an active agricultural landscape.
Pearce, academic colleagues and others within the renewable energy sector are in the early stages of researching how agrivoltaics could work in the Canadian landscape and conditions.
Part of the process will involve identifying policy changes that would encourage more widespread solar technology proliferation.
This could include policies that lower the costs of building solar energy projects. That would give companies more opportunities to lease land from farmers (similar to what is common for windmills), and allow landowners to more economically build and then benefit from their own larger-scale solar projects.
Another objective is identifying the structural designs best suited to different crops and production methods.
Different crops could benefit in different ways. For example, partial shade provided by overhead panels could reduce evaporation of irrigation water in high-value crops. However, in unirrigated corn fields, the same setup would create field obstacles for no production benefit.
In the latter case, strategically placed rows of vertical panels could prove more effective. For crops requiring full sun, panels using nearly transparent energy collection cells might be the answer.
“Europe and the United States are ahead of us. I think it behooves us to do some of the research now,” says Pearce, referencing the case of an Arizona pepper farm where solar panel shade spurred yield increases.
“We’re trying to move agrivoltaics forward. The idea is to add solar to farms without taking anything away.”
Pearce and his colleagues hope to establish 10 Ontario field research plots spanning a variety of agricultural commodities and landscapes in summer 2023. That would be the first step toward determining what systems could work in Ontario, and filling the agrivoltaics information vacuum.
Pearce says urban and industrial areas – new home developments and parking lots, for example – also have a role to play in solar capture. He believes a perfect world would include solar panel mandates for all new housing and industrial development.
But even if every new house and parking lot had solar panels, more energy would be required. Determining how to generate that power in the countryside, without adversely affecting food production, is ideal.