Improving Productivity of Cropland through Agrivoltaics

The concept of combining photovoltaics (PV) with agriculture (agrivoltaics or APV) is being explored across the globe and has established field trials in countries including, but not limited to, Germany, Vietnam, Italy, France, Japan and Chile. An agrivoltaic system involves positioning solar panels directly above or near active agricultural land to provide some form of shading to the crops and to generate electricity from the solar array. The usefulness of this concept is seen when considering the abundance of land that becomes available to the PV market if that land can be shared with the agricultural sector. For instance, consider that in 2016 Australia used 372 million hectares of land for agriculture, of which 8.3% was designated cropland. Therefore, even if some proportion of this cropland (say an 8th) are retrofitted with overhanging PV systems, Australia’s effective solar generation area would increase by roughly four million hectares. This would greatly enhance the renewable energy sectors ability to satisfy baseload energy requirements of the national grid. At first glance the concept of shading plants seems counterintuitive to the perception that cropland should be without obstructions. However, agrivoltaics recognises that crops do not require every hour of sunlight to photosynthesise. Consequently, the solar energy resource can effectively be shared with photovoltaic technology to increase the productivity of the land without greatly decreasing the yield of the crop, and in some cases, increasing crop yield. This is achieved by spacing the rows of solar panels in such a way that the shadows caused by the panels still permit crops to photosynthesise sufficiently in addition to reducing heat related stress caused by the environment. As such, this study aims to review existing literature about agrivoltaics and use experimentation to explore if the advantages they provide are great enough to justify their introduction into Australian agriculture. A key parameter for this study is land productivity that is measured using “land equivalent ratio” (LER) which is a combination of crop yield (measured in kilograms) and energy production (measured in watt-hours).