A collaborative report involving The Nature Conservancy, American Farmland Trust, Washington State University, and the Spatial Climate Solutions Lab at UC Santa Barbara has highlighted the significant potential for agrivoltaics within Washington State's extensive apple orchards. The findings underscore substantial acreage synergies and economic benefits, positioning apple orchards as particularly suitable candidates for co-located solar energy generation and crop production.

The in-depth analysis revealed that elevated single-axis tracking solar arrays in apple orchards can dramatically reduce sunburn risk, with reported reductions ranging from 34% to an impressive 95%. This performance often surpassed that of conventional shade cloths. While denser tracking arrays proved more effective in mitigating sunburn, researchers noted a slight corresponding yield loss due to increased shading. Crucially, the economic benefit derived from the reduction in sunburnt apples outweighed the yield reduction, leading to an overall increase in the percentage of marketable fruit.

Despite requiring more expensive elevated structures to position panels above tree canopies, the levelized cost of electricity (LCOE) for apple agrivoltaic systems was estimated between $70/MWh and $85/MWh. This range remains competitive with, and comparable to, utility-scale solar projects elsewhere in the United States, particularly those at similar latitudes and solar radiation levels. The report emphasized that single-axis tracking panels are generally more appropriate for apple orchards due to their typical north-south orientation, though perpendicularly racked fixed-tilt panels can also be effective. The most cost-effective deployments were identified in key apple-growing regions such as Yakima, Benton, Grant, and Chelan counties.

For cider apple orchards, where fruit quantity often takes precedence over blemish-free quality, the shading benefits of agrivoltaics are less of a primary driver. However, the report identified significant economic opportunities for cideries through onsite solar generation, which can meet their substantial energy demands for apple pressing, cold storage heating, and pasteurization. Additionally, dual-use land opportunities, such as integrating solar with hedgerows or windbreaks, can provide economic value without negatively impacting fruit yield.

High-value table and dessert apple varieties, including Honeycrisp and Cosmic Crisp, as well as cherries, stand to gain considerable economic advantages from agrivoltaics due to their susceptibility to sunburn and late frost damage. The capital costs associated with traditional trellising systems ($4,000 per acre for poles) and shade cloth installation ($2,000 to $13,000 per acre) could be partially offset by the investment in elevated solar panels, which also provide insulation against frost. Overall, the authors concluded that well-designed agrivoltaic systems significantly improve land use efficiency, demonstrating that one acre of agrivoltaics can produce as much combined lettuce and solar energy as 1.7 to 1.9 acres dedicated to each use separately. While agrivoltaic projects are typically costlier than standard ground-mounted solar, they remain more economical than rooftop solar installations. The report concludes that widespread adoption in Washington will necessitate sustained investment in research and demonstration, robust cross-sector collaboration, targeted financial incentives, and innovative policy solutions.