Agrivoltaics for small ruminants: A review

The mitigation of climate change will require the large-scale uptake of renewable energy generation, in particular wind and solar. Utility-scale solar photovoltaics (PVs), or solar farms, will necessitate the transformation of agricultural land. Agrivoltaics is the dual land-usage solution with the integration of solar PV arrays with ongoing agricultural production.

The farming of ruminants, especially sheep, is particularly suited for agrivoltaics in that little modification of the infrastructure is required to accommodate sheep grazing beneath and between the PV arrays. However, many uncertainties remain and this review paper provides more insights into the technology, the role of small ruminants, the potential impacts on agriculture productivity and the land, as well as other sustainability aspects of agrivoltaics.

Previous and ongoing research suggests there are (potentially) mutual benefits for both operations to occur on the same land – if the integration is designed well. The sheep aid solar farm operators with maintenance aspects, specifically vegetation management and associated costs. The PV arrays influence the microclimate conditions on the farm in terms of wind speed (and direction), temperature and humidity, including rain distribution, providing for better animal welfare in terms of heat stress and protection against harsh weather – especially in the face of climate change.

The construction process does have a negative impact on the soil, but the land can be restored in a short period of time. Once operational, the soil is positively impacted with better moisture retention and vegetation growth improves in hotter months. The widespread shading also means (potentially) a better distribution of urination events with less overloading on the land and lower leachate, although more field trials are required.

Overall, the available evidence suggests that the environmental performance of agrivoltaics is positive. Apart from the impact on the land, the life cycle of the systems have low material and carbon footprints, with short carbon and energy payback periods, emphasising the role of agrivoltaics in the energy transition. Further quantifications of many aspects are needed with longitudinal data from different climate contexts around the world.