Os agrovoltaics represent a sign of hope in terms of sustainability process in this era of climate changes. They refer to the simultaneous use of an area for Agricultural production e electricity generation from Photovoltaic systems.
Until recently, agricultural land and ground-based photovoltaic systems existed separately. Now, anyone who purposefully combines the two forms of land use can benefit from positive effects of this practice.
Favorable math: agrovoltaics make extremely efficient use of land
First, let's assume that the assembly of photovoltaic panels takes up a maximum of 15% of an agrovoltaic area, or that they generate a lot of shade for crops.
Secondly, the electricity yield will be around 20% lower due to the greater spacing between the lines, compared to a conventional ground-mounted photovoltaic system.
With this, the agrovoltaics improve by up to 85% plus 80%, that is, by up to 165% overall productivity. The extremely efficient use of land is the main argument in favor of agrovoltaics.
Around the world, agriculture is facing extreme weather events, such as heavy rain, increased heat and hail.
“In these cases, we can even use a photovoltaic system to protect plantations”, explained the Dr. Kerstin Wydra, Professor of Plant Production and Climate Change at the Erfurt University of Applied Sciences.
“Thus, agrovoltaics offer a great opportunity as agriculture adaptation strategy climate extremes that are already occurring and those that are likely to occur in the future. Ultimately, all of this affects soil and biodiversity.”
In a study, she and her colleagues investigated the potential of agrovoltaics for the German state of Thuringia. The result was that “the dual use of arable land for food and solar energy can give a significant contribution to stop the warming from our planet and guarantee the food supply.”
Solar biodiversity
Conventional photovoltaic systems installed in the field are best suited for low-quality soils, paved surfaces or surfaces that are difficult to access. The most important thing to consider when assembling the modules is optimizing solar orientation.
In the agrovoltaic model, the photovoltaic system can help with the crop and have a very different appearance, explained Dr. Kerstin Wydra. The possible applications are as broad as the technology.
Photovoltaic systems are available as rigid sun-tilted or vertical structures (as in solar facades), in the form of flexible thin-film photovoltaic modules or organic photovoltaic cells, in more or less transparent designs, and as tracking systems that automatically follow the position of the sun.
For example, for an apple orchard where trees have existed for many years, a fixed structure three meters high is a good solution. On a poultry farm, where photovoltaic modules are intended to protect animals from the sun and birds of prey, they can be mounted between 70 cm and 100 cm in height.
For greenhouse crops, the conventional glass structure can be replaced totally or partially by photovoltaic elements. The same applies to anti-hail nets and tarpaulins for growing fruit and vegetables.
Vertical photovoltaic elements between rows or as crop or pasture boundaries are typically bifacial, meaning they absorb sunlight from both sides, thus providing solar energy at different times of the day.
Controllable panels are ideal for optimizing harvest power and yield. If the apples need a few days of sun to ripen, the covers can be folded up to get out of the way.
And it's not too big a leap for smart solar farming, where photovoltaics adjust to oncoming hailstorms with the help of Internet weather data.
Agrovoltaics as a complete solution
Agrovoltaics (or agrophotovoltaics) refers to the simultaneous use of agricultural land for food production and energy generation using photovoltaic systems.
The Fraunhofer Institute for Solar Energy Systems has been researching agrovoltaic systems for decades and uses the term to define systems in pastures, arable agriculture and horticulture, but not for closed installations or aquaculture.
In addition to energy generation, agrovoltaic solutions offer additional benefits for practically all forms of agricultural production, such as:
- Protection against seasonal phenomena, such as frost or drought;
- Protection against extreme weather conditions: drought, hail, frost;
- Less irrigation due to shading;
- Better growth in case of shade-tolerant plant types;
- Protection against birds of prey where birds are raised outdoors;
- Protection against heat and solar radiation for workers.
In 1981, the trade magazine Sonnenstrom published an article titled “Potatoes under the collector”. The article was written by the founder of the Fraunhofer Institute for Solar Energy Systems, which since 2014 has been researching the viability of agrovoltaics in several studies and pilot projects in the Rhineland, as well as in Algeria, Chile and Mali.
When the cost of photovoltaic modules started to fall a few years ago, there was new space to experiment with ideas previously considered “crazy”, explained Sophia Judith Bächle from Fraunhofer ISE.
And of course, the political will to promote such projects also contributed to the agrovoltaic scenario finally becoming a reality.
Daniel Rosende Völker, managing director of SMA AG for Latin America, sees a growth trend. “Our clients are increasingly interested in mixed-use land. This is an important approach. After all, we need large areas for the production of renewable energy for the energy transition to be successful. And if we use these areas in multiple ways, we will be on the right track.”
Pioneering in agrovoltaics
When hay and forage production was no longer sufficient to ensure the survival of Jack's farm in Boulder County, Colorado, his grandson Byron Kominek went in search of a new source of income.
Thus, in 2019, the Jack's Solar Garden, a collaborative project with researchers from DONATE (United States Department of Energy), NREL (National Renewable Energy Laboratory), Colorado State University and the University of Arizona.
Today, Jack's Solar Garden is not only the largest agrivoltaics research facility in the United States, but also a community project. A portion of the electricity generated is reserved for low-income families.
The environmental organization National Audubon Society is planting its largest pollinator protection zone around the photovoltaic system. And the Agrivoltaic Learning Center educates students, citizens and political decision-makers about the dual use of land to produce clean energy and local food. know more about Byron's vision for Sonnenallee.
On the rise all over the world
It will likely be some time before nurseries, vineyards and potato fields are covered with enough photovoltaic panels.
Countries where the consequences of climate change are already clearly felt, and politicians are defining other sustainability priorities, are further along in this sense.
“China has the largest plant capacity, with 12 gigawatts of nominal power. Worldwide, it’s 14 gigawatts,” said Dr. Kerstin Wydra.
In Japan, with its scarce arable land, government support measures have been in place since 2013 and there are already around 2.000 agrovoltaic systems with 120 different crops being grown and thriving, such as berries, grains, mushrooms, tea, coffee, vegetables and herbs.
Daniel Rosende Völker is impressed. “In principle, the potential for agrovoltaics in Latin America and in any other region with a relevant agroindustry is enormous. There are clear technical solutions to industry challenges that are now also commercially attractive.”
Pilot and research plants currently predominate in Central Europe, but commercial operation is becoming increasingly realistic. And the droughts that wreaked havoc in the summer of 2022 make agrivoltaics an attractive option for farms looking to combat the effects of climate change.
The opinions and information expressed are the sole responsibility of the author and do not necessarily represent the official position of the author. Canal Solar.
