Energy and water co-benefits from covering canals with solar panels

Abstract

System (CIMIS). While the modified Penman-Monteith approach estimates evaporation from an open water body directly, parameter conversions are required to convert pan evaporation and CIMIS landsurface evaporation into open-water-body evaporation. We examined the net effect on financial performance using the System Advisor Model (SAM) and a sensitivity analysis that included estimates of three different solar PV structures at eight different sites along the California network of canals (Fig. 1). In our main results we considered CdTe semiconductor technology but also considered multicrystalline silicon in the sensitivity analysis. The three solar PV structures included a ground-mounted system (Fig. 2a), a steel-truss canal-spanning design that has been deployed in Gujarat, India 26 (Fig. 2b), and a suspension-cable canal-spanning design 27 that has been deployed in Punjab, India 28 (Fig. 2c). Our financial performance analysis includes NPV and levelized cost of energy (LCOE) comparisons of over-canal to ground-mounted designs. Our design comparisons considered enhanced PV performance due to evaporative cooling, and avoided costs for water and aquatic weed mitigation (Fig. 2d and 2e). ResultsHere, we present the results of our water savings, financial performance, and diesel engine retirement analysis. Water savingsEvaporation rates extracted to the locations of the canals and averaged annually are 1716, 1497, and 1570 mm y -1 for the modified Penman, pan evaporation, and CIMIS approaches, respectively. As expected, these estimates of evaporation from canal water surfaces are higher than estimates of evaporation from land surfaces due to the availability of water and surface energy balance. Our surface water evaporation estimates are 11% to 59% higher than California statewide potential evaporation from land surfaces 29,30 . Similarly, previous estimates of evaporation from water surfaces on lakes are generally larger than potential evaporation from land surfaces 31 .

A Review of Current Activities and Future Trends in Agrivoltaics

“…The collected rainwater from AV can be used both for cleaning PV and irrigation [21]. 110 foot-wide PV shades will be mounted over irrigation canals in California (Project Nexus in Turlock Irrigation District), which is similar to an earlier project in Gujarat, India [42].…”

Environmental and Circular Economy Implications of Solar Energy in a Decarbonized U.S. Grid

“…Another recent study estimated the potential for use of the 6,350-km California canal network for generating electricity using PV mounted over the canals. 186 The authors estimated that the net present value of this system would exceed the value of conventional overground solar by 20%-50%, and that the system would reduce annual evaporation by an average of 39,000 m 3 per km of canal. Such systems show particular promise for water-constrained areas such as California.…”

Floating photovoltaics performance simulation approach

“…So far in literature, FPVs performance assessments were based on conventional ground PV modelling and simulation tools/software, where several modifications are required. For instance, the System Advisory Model (SAM) was used by McKuin et al [ 17 ] to understand the techno-economic analysis of water-based PV systems in California to power pumping systems. Song and Choi [ 18 ] analysed the potential of FPV systems on a mine pit lake in Korea using SAM to conduct energy simulations based on local weather data and the system design.…”