One outcome of the drawn-out, tawdry affair that was the UK’s Conservative leadership run-off this summer was a complete leadership vacuum at the top of government for two months. While the rest of Europe squirrelled away gas supplies for the bleak winter ahead, the UK sat on its hands. As a result, the country has just nine terawatt-hours (TWh) of gas stored – compared with 217TWh in Germany, 122TWh in France and 162TWh in Italy – heading into the worst energy crisis since the 1970s.
In the Tory leadership contest, one strange source of consensus between rivals Rishi Sunak and Liz Truss was a shared distaste for solar panels – particularly those parked on British farmland. “I am somebody who wants to see farmers producing food… not filling fields with paraphernalia like solar farms,” Truss told party members in Darlington. Sunak meanwhile promised Telegraph readers that, under his leadership, Britain would “not lose swathes of our best farmland to solar farms” and that he was committed to “making sure our fields are used for food production and not solar panels”.
However, if either of the candidates’ army of researchers had typed “solar” and “farming” into Google, they would have come across a handy solution that could combat the food and energy crises simultaneously: agrivoltaic farming.
The global economy continues to suffer from a series of destabilising shocks. The two-plus years of the Covid-19 pandemic and the subsequent crisis in Ukraine, with global effects on commodity markets, supply chains and inflation, have resulted in soaring food and energy prices. Coupled with the devastating effects of climate change, and the resultant diminishing yields of upcoming harvests, all this means that food and energy insecurity is fast increasing around the world.
“[But] with the right investment, innovation and robust collaboration, agri-food systems could become one of the world’s most hopeful solutions to climate change, as well as reduce poverty and provide nourishment for all,” says Sean de Cleene, head of the Food Systems Initiative at the World Economic Forum (WEF).
According to de Cleene, there are several agri-food technologies – including digital and data advances, off-grid renewable energy solutions and alternate proteins – that could, when scaled, “support a more positive food future and improve food system efficiency, especially during a time of crisis”. For instance, the WEF estimates precision agriculture could reduce water use by more than 5% and off-grid renewable energy production could generate up to $100bn in additional farmer income by 2030.
There is, however, an estimated $15.2bn financing gap for food systems innovation, according to the final report from the Commission on Sustainable Agriculture Intensification. This brought together Global South scientists, policymakers and experts to solve global agri-food systems challenges. “Investing in and financing [the roll-out of] agri-food technologies will support the scale and adoption of appropriate innovation and drive progress in the food systems,” says de Cleene.
Agrivoltaic farming is a “win-win”
One agtech solution, agrivoltaic farming, could bring huge benefits to the energy and food sectors. Essentially, agrivoltaic farming integrates solar photovoltaic (PV) projects within an agricultural activity so the same land area can be used for both. Combining renewables and agriculture holds substantial potential to reduce global greenhouse gas emissions, protect biodiversity, lower dependence on imported fossil fuels as well as improve farming productivity.
“The hallmark characteristic of agrivoltaics is the sharing of sunlight between the two energy conversion systems: photovoltaics and photosynthesis,” says Jordan Macknick, lead energy-water-land analyst at the US National Renewable Energy Laboratory. “It essentially mimics what humans have been doing for hundreds of years with agroforestry – think shade-grown coffee – intentionally creating partial shade to create multiple layers of agricultural productivity on the same piece of land.”
Solar shading can protect crops from adverse weather effects and reduces evapotranspiration, keeping the soil moisturised. This can prevent desertification or help revegetate desertified land. According to the trade association SolarPower Europe solar shading could save 14–29% of water depending on the level of shading. The approach could provide a much needed shot in the arm for food production in a future of longer and harsher droughts.
“We don’t have to ‘struggle for land’ anymore and we can increase renewable energy generation and agricultural production at the same time: it’s a win-win,” says Kristian Ruby, secretary-general of European electricity trade association Eurelectric.
There are various types of agrivoltaics, including ground-mounted PV panels, elevated PV panels and solar greenhouses, which combine with different types of crops. The best approach depends on the area’s climate and land-use patterns.
Elevated PV panels, for instance, can be coupled with larger crops and harvests such as fruit trees or vineyards. Ground-mounted large-scale PV arrays, on the other hand, can be matched with low-height crops and livestock. The panels can increase animal welfare by providing easy access to shade while enabling permanent vegetation to be planted between and below them for grazing.
Agrivoltaics also offer the opportunity to intentionally provide a variety of ecosystem services such as habitat creation, support for beneficial insects such as bees, natural vegetation restoration, and cover cropping for soil health benefits and carbon sequestration.
“As agrivoltaics involve strategic shading of the ground, it can often make the most sense in areas where you have an excess of sunlight and not enough water – in the US south-west, for example,” says Macknick. “We have particularly noticed improvements in agrivoltaic settings for peppers and tomatoes in the US south-west, and for leafy greens everywhere.”
There are a number of agrivoltaic projects dotted across the US. In Rockport, Maine, University of Maine researchers are studying the impact of solar panels installed over 11 acres of blueberry farmland. In Grafton, Massachusetts, farmers are working with University of Massachusetts academics to figure out which crops perform best under solar panels' shade. In Longmont, Colorado, Jack's Solar Garden has established itself as the country's largest commercially active site for agrivoltaics research, and researchers at Oregon State University are experimenting with growing crops between traditional utility-scale solar PV panels that are not elevated.
In Europe, one of the leading examples of the approach is an agriphotovoltaic demo project designed by Italian utility Enel Green Power. Enel has identified different types of land for arable and pastoral farming across Italy, Greece and Spain that can coexist with solar power plants without having to significantly modify plant layout – thereby containing costs and boosting competitiveness. Nine PV installations were built in different climate regions together with a network of remote and nearby sensors. The testing under way is evaluating the impacts of different agricultural activities with a variety of solar technologies (fixed and trackers, which orientate towards the sun), panels (monofacial and bifacial) and layouts. The crops include aromatic, medicinal and medical herbs, food plants such as vegetables and pulses, cosmetic plants like aloe, fodder plants and flowering plants to attract pollinators.
“The data gathered from these experimental installations will tremendously help future integrated projects improve local farming competitiveness by modernising and integrating it with solar tech, so that we can improve local agriculture resilience while decarbonising the sector by increasing the renewable energy capacity,” says Ruby.
In Germany, installing agrivoltaics on 10% of farms with particularly beneficial conditions could provide around 9% of the country’s electricity demand, according to a recent study by the University of Hohenheim (Stuttgart) and the Thünen Institute (Braunschweig). That would consitute just 0.7% of German arable land – around 85,000 hectares.
Still in its infancy
The road ahead for agrivoltaics is not without its obstacles, however. Many of the promising projects are still in their experimental phase; the main challenge will be coming up with an optimal model of integrated management for the farming activities and PV plants' operation and maintenance, that can easily be reproduced and scaled up.
Public incentives will be required to attract commercial interest and scale up the sector. “[And] it goes without saying that faster permitting should be a must to enable agrivoltaic implementation,” adds Ruby.
For Macknick, one of the major barriers is cost, as it can be increasingly expensive to elevate PV panels due to the rising prices of steel and installation labour.
A second major issue he sees is the compatibility of the agrivoltaic system with existing farming practices. Agrivoltaics will only be successful if the farmer is both motivated (typically financially) and has a practical ability to farm the plot without major inconveniences. Most solar installations today are not designed to be farmer-friendly, and Macknick points out that even many existing agrivoltaic installations have not incorporated as many farmer-friendly aspects as farmers would like.
“Getting farmers more involved in the design phase of agrivoltaics and having them contribute to modifications could be really useful for overcoming that barrier,” he says.
Essential to net zero
By enabling even broader development of solar power, agrivoltaics are destined to play “an essential role in the net-zero transition”, according to Macknick. They allow for solar power to be developed in areas where there would otherwise be pushback against renewable energy development, such as the rural British communities Truss and Sunak tried to court with their shortsighted attacks on solar farms. Agrivoltaics actually offer the opportunity to support both agriculture and energy on the same piece of land, benefitting multiple stakeholders at once.
The different types of agrivoltaics will likely end up suiting particular niches. According to Macknick, projects with pollinator habitats and sheep grazing would be better suited to larger installations of more than 300MW, whereas crop production agrivoltaics would be best applied to installations no larger than 5MW, “unless there are innovations in how agrivoltaics crop production can be implemented at scale without drastically increasing the costs of solar construction”, says Macknick. Nonetheless, he foresees these crop production sites becoming increasingly important near urban centres where the produce can readily enter high-end food distribution markets such as farmers markets, restaurants and community-supported agriculture programmes.
In short, the future looks bright for agrivoltaic farming. According to SolarPower Europe, if agrisolar was deployed on just 1% of Europe’s arable land, its technical capacity would amount to more than 900GW, more than six times the current installed PV capacity in the whole of the EU. “There is a huge opportunity here and the market is really starting to develop,” says Ruby.