Aquavoltaics: Synergies for dual use of water area for solar photovoltaic electricity generation and aquaculture

Bodies of water provide essentials for both human society as well as natural ecosystems. To expand the services this water provides, hybrid food-energy-water systems can be designed. This paper reviews the fields of floatovoltaic (FV) technology (water deployed solar photovoltaic systems) and aquaculture (farming of aquatic organisms) to investigate the potential of hybrid floatovoltaic-aquaculture synergistic applications for improving food-energy-water nexus sustainability. The primary motivation for combining electrical energy generation with aquaculture is to promote the dual use of water, which has historically high unused potential. Recent advances in FV technology using both pontoon and thin film structures provides significant flexibility in deployment in a range of water systems. Solar generated electricity provides off-grid aquaculture potential. In addition, several other symbiotic relationships are considered including an increase in power conversion efficiency due to the cooling and cleaning of module surfaces, a reduction in water surface evaporation rates, ecosystem redevelopment, and improved fish growth rates through integrated designs using FV-powered pumps to control oxygenation levels as well as LED lighting. The potential for a solar photovoltaic-aquaculture or aquavoltaic ecology was found to be promising. If a U.S. national average value of solar flux is used then current aquaculture surface areas in use, if incorporated with appropriate solar technology could account for 10.3% of total U.S. energy consumption as of 2016.