OOS 21-9 - Agrivoltaics in drylands: Co-location has food, water, and renewable energy benefits

Thursday, August 15, 2019: 10:50 AM
M107, Kentucky International Convention Center
Greg Barron-Gafford1, Mitchell Pavao-Zuckerman2, Rebecca L. Minor1, Isaiah Barnett-Moreno1, Kirk Dimond3, Andrea Gerlak4, Patrick Murphy5, Moses Thompson6, Christina Winkler7, Sallie Marston8 and Jordan Macknick9, (1)School of Geography & Development; Biosphere 2, University of Arizona, Tucson, AZ, (2)University of Maryland, College Park, MD, (3)School of Landscape Architecture and Planning, University of Arizona, Tucson, AZ, (4)University of Arizona, (5)Department of Geosciences, University of Arizona, Tucson, AZ, (6)Tucson Unified School District, Tucson, AZ, (7)Ecology & Evolutionary Biology; Biosphere 2here 2, University of Arizona, Tucson, AZ, (8)School of Geography & Development, University of Arizona, Tucson, AZ, (9)National Renewable Energy Laboratory
Background/Question/Methods

The vulnerabilities of our food, energy, and water systems to projected climatic change make building resilience in renewable energy and food production under an increasing stressful climate a fundamental challenge. We investigate a novel approach to solve this problem by creating a hybrid of co-located agriculture and solar photovoltaic (PV) infrastructure - agrivoltaics - to maximize agricultural production and improve renewable energy production, all while reducing demand for water for irrigation. We take an integrative approach - monitoring microclimatic conditions, PV panel temperature, soil moisture and irrigation water use, plant ecophysiological function, phenology, and plant biomass production within this novel agrivoltaics ecosystem and in traditional PV installations and agricultural settings (control plots) to quantify trade-offs associated with this system.

Results/Conclusions

We find that shading by the PV panels provides multiple additive and synergistic benefits. In terms of water, levels of soil moisture remained higher after each irrigation event within the soils under the agrivoltaics installation than the traditional agricultural setting, indicating that less irrigation was required to maintain adequate moisture conditions. As a result, we find reduced drought stresses on photosynthetic capacity, extended growing seasons, and water use efficiency and greater food production in the agrivoltaic installation relative to the control plants. Combined with localized cooling of the PV panels resulting from the transpiration from the vegetative “understory”, which reduces heat stress on the panels and boosts their performance, we are discovering a win-win-win at the food-water-energy nexus. The results presented here provide a foundation and motivation for future explorations towards resilience of food and energy systems under the future projected increased environmental stress involving heat and drought.