When we talk about agrivoltaics, the coexistence of photovoltaics, agriculture and animal husbandry on the same land, there is no shortage of astonishment and even perplexity: how is this coexistence possible? What are the benefits? And are they quantifiable? And so, in order to find answers to the most frequently asked questions, we tried to put ourselves in the shoes of those directly affected, farmers and animal breeders, and we did so with numbers at the ready. The increase in yield for the farmer In order to understand the benefits are for a farmer, we conducted several tests, in various climate zones. We began in the United States, then in Italy, Spain and Greece, and also in Australia. Furthermore, in Italy, with Agrivoltaico Open Labs, we are working on innovation together with universities, startups and research institutes. These tests have shown that, by combining photovoltaic technology with agricultural activity, a higher yield per unit of cultivated area is achieved, with values that are between 20 and 60% higher, depending on the type of crop. The use of herbs, flowers, and mixtures of floral and tree species that can attract pollinator species has also been tested, giving rise at the Las Corchas solar plant in Spain and at the Pezouliotika solar plant in Greece to new domestic bee farms where the highest quality honey is produced, thereby bringing new life to the local economy. But back to the land and the farmer: the first secure income comes from renting or selling part of the land for the installation of solar panels. This is a risk-free yield. It is independent of crop market prices and seasonality, and without associated costs. Cultivation is in fact possible between the rows of panels, and also, depending on the species chosen, under the panels. And so there is, at least in part, a possible dual use of the rented land. The increase in yield due to the protective effect of the panels isn’t just a question of theory: for forage between the rows of panels there is a 40% increase, for strawberries an 18% increase between the panels, a 14% increase under the panels, and it goes up to +36% using LED backlighting. For thyme there’s a +20% yield, oregano +15%, eggplant +30%, aloe +30%, and peppers +60%. Furthermore, the presence of electrical infrastructure in agriculture has another beneficial aspect: it enables the development of Agriculture 4.0 techniques, which can be a source of additional benefits for the farmer in terms of costs, water consumption and the sustainability of the agricultural process. All the questions (and answers) about agrivoltaics With agrivoltaics, the increase in yield for the farmer for the same area under cultivation is therefore shown by the tests and the data, but there are still a few issues to be addressed. Why does the yield increase? While it is true that the panels partially shade, it is also true that a little shade isn’t bad for the plants, and the soil, considering that the summer period is often subject to high temperatures and heat shock. The soil is thus able to retain more moisture, thereby creating a favorable microclimate; therefore, it also needs less irrigation (reduction of up to 20%), reducing costs and risks, as periods of drought are increasingly frequent. Which plants should be grown between panels while producing renewable energy? The list is varied: for example, broccoli, peppers and onions, but also herbs and medicinal herbs. Or eggplant, zucchini and cilantro; nor should we forget strawberries and aloe. We can also add many other leguminous and forage plants. It is clear that each type of soil and climatic area has its own specificity that needs to be considered. Not all crops are possible everywhere, in some cases the choice will be forage and in others horticulture, or even aromatics: the type of cultivation always depends on the soil, climatic conditions and the interests of local farmers. And how does the environment respond? The answer is immediate: reduced water consumption with increased production, reduced CO2 emissions (for photovoltaic production), increased biodiversity and pollinating insects. But has anyone in Italy really tried this? The answer is yes. We are seeing plenty of experimentation and innovative business model approaches with our open labs, while many people are introducing agrivoltaics, on their own land. For example, in Tarquinia, in the Piani della Marina locality, where part of the land has been leased for an approximately 170 MW photovoltaic plant, the largest solar plant in Italy. And soon, site openings are already planned for two more agrivoltaic plants, for 13 and 55 MW respectively.
