The boundless potential of solar panels over farmland

Two years of testing in a pear orchard resulted in the following knowledge: 16 percent loss in yield but no quality loss. “The pears were slightly smaller in size but that’s acceptable. This is because the loss in weight yield is more than compensated by the extra energy yield of the solar panels. This is beneficial for the pear grower because selling electricity is more lucrative these days than selling fruit and vegetables.”

A major challenge is finding the ideal positioning of the solar panels. This is easier with permanent crops, such as pear trees or other orchard trees. “This enables you to find a setup that is little invasive. In our trial project we replaced the hail nets that protect the pear trees with semi-transparent solar panels.” On fields with crop rotation it’s a different story because every crop will react differently to the solar panels. For crop rotation vertical solar panels are currently being tested as a potential elegant solution.

Together with Jan Cappelle’s research group

Bram Van de Poel and his team looked for solutions. “Computer models enable us to use 3D simulations to find different solar panel configurations: with minimum yield loss, maximum crop protection and an interesting financial return from the solar panels Those configurations are currently being tested on two trial fields with wheat and fodder beets.”

Solar panels create a favourable microclimate

So for the pears there is a slight yield loss but on the other hand the researchers noticed the solar panels also had beneficial effects.

Bram Van de Poel: “Pear trees under solar panels are more resistant to drought and the fruit is less prone to sunburn. With springtime frost, temperatures under the solar panels are half a degree higher: that can mean the difference between crop loss due to frost damage or no crop loss. With our research and computer simulations we are looking for synergies that bolster these beneficial effects.”

A great deal of interest from the field

These positive results have been generating a great deal of interest: from farmers but also from other interested parties. “Businesses are often located next to farmland. They have a high energy requirement but maybe their roof area is already covered in solar panels. In such cases a partnership with their neighbouring farmer is an interesting option to make their energy use more sustainable. We also work with energy and civic cooperatives that invest in green energy together. Thanks to the new legislation on sharing power you can now invest in a solar park together.”

Legislative framework is lagging behind

For the time being this is limited to research because there is an important obstacle standing in the way of dual land use: the legislative framework. “Some farmers want to invest in agrivoltaics today but right now we have to disappoint them. The legislative framework is not fully in place. But we’re getting there. More and more policy makers are catching on to the benefits of agrivoltaics. We are a strong advocate of a guideline framework that provides clarity so farmers and companies can get started on agrivoltaics.”

Immense potential

But would agrivoltaics really make that much of a difference? Bram Van de Poel has no doubt. “This has been confirmed by our calculations. Using just one percent of Flanders’ farming area for agrivoltaics would be enough to make the entire agricultural sector energy neutral. And that would still leave 99 percent. So the potential is boundless.”