Farming Meets Solar: The Rise of Agrivoltaics in the Quest for Net-Zero

As industries around the globe work towards achieving net-zero emissions, there is a pressing requirement to reduce emissions across every sector. Agriculture is particularly significant since it contributes to approximately 22% of global greenhouse gas emissions.

One approach to decarbonizing agriculture is by deploying solar panels, known as photovoltaics (PVs), within fields that cultivate crops, in greenhouses, and on livestock farms. This method, commonly termed agrivoltaics, allows farmers to decrease their carbon emissions while continuing to produce food.

Agrivoltaics also tackle a significant critique often aimed at solar energy, which is the belief that solar farms “consume” extensive areas of farmland suitable for agricultural use. In truth, solar farms currently cover only 0.15% of the total land in the UK, which is minimal compared to the 70% of land designated for agriculture.

The simplest form of an agrivoltaic system consists of placing conventional crystalline silicon PVs (the predominant type of solar panel) in fields alongside livestock. This diversification method has gained traction in recent years for three main reasons.

First, it enhances biodiversity since fields are not limited to a mono-crop but benefit from crop rotation and are not exclusively harvested for silage. Second, it increases productivity as livestock can utilize shade and the resulting healthier pasture growth.

Lastly, the solar farm reduces maintenance costs since livestock can naturally manage grass height. This occurs while the solar panels produce clean, local energy.

Nonetheless, improper arrangement of agrivoltaics can lead to complications. A primary concern in crop-growing fields is balancing the sunlight needs of crops with those of solar panels. Crops need light for growth, and if solar panels block excessive light, it may negatively impact crop yields.

An agrivoltaic canopy installed in France. Image: Shutterstock

This challenge differs by location. In areas with fewer sunny days, like the UK, solar panels should allow more light to pass through. In sunnier regions such as Spain or Italy, some shade can actually benefit crops by alleviating heat stress during scorching summer months. Achieving the right balance is critical and depends on local conditions, crop types, and the requirements of pollinators like bees.

The complexity increases with the selection of PV materials. Traditional solar panels may not always be the best fit as they often filter out light wavelengths essential for plant growth.

Innovative options, such as organic semiconductors and perovskites, offer potential benefits as they can be customized to let through the required light for crops while simultaneously capturing energy. Unlike traditional inorganic semiconductors, which are primarily metallic crystal structures, organic semiconductors mainly consist of carbon and hydrogen. Perovskites, conversely, provide a blend of organic and inorganic semiconductor traits.

There exists a multitude of material combinations to consider, with extensive scientific literature investigating various possibilities. Identifying the optimal fit can be quite challenging.

This is where computational tools come in. Instead of testing each material in practical scenarios – which could be time-consuming and costly – researchers can use simulations to estimate their performance. These models help identify the best materials for specific crops and climates, conserving both time and resources.

The tool

We have developed an open-source tool designed to compare various PV materials, streamlining the identification of the best options for agrivoltaics. This tool leverages geographical data alongside realistic simulations of the performance of different PV materials.

It assesses how light interacts with the materials in terms of penetration and reflection, along with other essential performance indicators such as voltage and power output. The tool can also incorporate laboratory measurements of PV materials and correlate them with real-world conditions.

By utilizing this tool, we modeled the energy generation capacity of different PV materials per square meter throughout the year across various regions and evaluated how much light could pass through these materials to ensure adequate crop growth.

An agrivoltaic installation over raspberry crops in the Netherlands. Image: Shutterstock

By employing these simulations across multiple materials, we identified the most suitable choices for diverse crops and climates.