DOI: 10.6071/m32h30
title: Energy and water co-benefits from covering canals with solar panels

description: In the manuscript entitled, "Energy and water co-benefits from
 covering canals with solar panels", we quantified the evaporation
 savings and financial performance of over-canal solar in comparison to
 over-ground solar on land adjacent to canals, using regional-scale
 hydrologic and cost simulations. We conducted regional hydrologic
 and techno-economic simulations of solar PV panels covering California’s
 6350 km canal network. We examined the net effect on the
 financial performance of three different solar PV structures at
 eight different sites along the California network of canals. The three
 solar PV structures included a ground-mounted system, a steel-truss
 canal-spanning design that has been deployed in Gujarat, India, and a
 suspension-cable canal-spanning design that has been deployed in Punjab,
 India. Our financial performance includes the net present value (NPV) and
 the levelized costs of energy (LCOE) comparisons of over-canal to
 ground-mounted designs considered enhanced PV performance due to
 evaporative cooling, and avoided costs for water and aquatic weed
 mitigation. Here, we provide the additional supporting
 information (Appendices A, B, and C) and the data we used to
 generate Figures 1, 3, and 4 in the main manuscript.
description: <em>Appendix A</em> We used the
 National Renewable Energy Laboratory's System Advisor Model (SAM)
 software (v. 2017.9.5) to conduct a techno-economic comparison of
 ground-mounted and over-canal solar PV systems. Here, we include the
 inputs to and the outputs from SAM as supplementary datasets. Appendix
 A1 includes screenshots of the inputs to SAM including location and
 resource, module selection, inverter selection, system design, shading and
 snow, losses, lifetime, battery storage, system costs, financial
 parameters, time of delivery factors, incentives, and depreciation.
 Appendix A2 includes the NPV and LCOE outputs. Appendix A3 includes the
 SAM outputs used in the sensitivity analysis. The workbook entitled
 "Edmonston_Sensitivity_Analysis.xlsx" includes the sensitivity
 analysis of the NPV of the suspension-cable design at the Edmonston
 Pumping Plant location. Here, we considered the parameters that
 contributed most to the variance in the standard deviations of our main
 results and the impact of alternative parameters that were not included in
 our main results. The workbook entitled
 "Edmonston_Alternative_SAM_Financial_Models.xlsx" compares the
 results of the ground-mounted system to the tensioned-cable system for the
 Edmonston Pumping Plant considering alternative financing approaches available in
 SAM and two
 federal subsidy rates (ITC of 22% and 10%). The alternative financing
 approaches include commercial, utility-scale
 PPA partnership flip with debt, utility-scale PPA
 partnership flip without debt, and utility-scale PPA
 sale-leaseback. <em>Appendix
 B</em> We fitted the distributions of our outputs
 from SAM with EasyFit Professional software (v. 5.6). Using the best fit
 distribution, determined with Kolmogorov-Smirnoff statistics, we%  ran
 Monte Carlo simulations of 10000 samples. Here, we include the inputs to
 and outputs from EasyFit as supplementary datasets. Appendix B includes
 the screenshots of the distributions of the NPV and LCOE as inputs,
 screenshots of the probability distribution functions, the goodness of fit
 summaries, summaries of the fitting results (e.g. fitting parameters), and
 the output of the random number generator (Monte-Carlo
 simulation). <em>Appendix C</em>
 We ran a percentile bootstrap analysis of 1000 replicates of the
 sample medians to estimate the 95% confidence intervals using the
 <i>boot</i> package in RStudio (v. 1.2.5033). Here, we include
 the inputs to and outputs from RStudio as supplementary datasets. Appendix
 C1 includes the Monte Carlo samples as inputs. Appendix C2 includes
 RStudio used to conduct the bootstrap analysis and the results (median and
 95% confidence interval).  
description: The attached appendices and supporting data for the figures in
 the main manuscript are provided to ensure the reproducibility of our
 study. There are no missing values in the input files.