Agrivoltaics in California: Solar Panels Paired with Farming, Vineyards, and Ranches

This guide explains what agrivoltaics actually means in California, the three main models that work in our climate, how the Williamson Act and Solar Use Easement rules apply, what landowners should expect from a developer lease versus owning the system, and how to evaluate whether your specific parcel in Temecula Wine Country, De Luz, Anza, Aguanga, or anywhere else in inland Riverside County is a fit.

What Agrivoltaics Actually Means

Agrivoltaics, sometimes written as agri-PV or dual-use solar, refers to any system where the same parcel of land simultaneously produces solar electricity and supports active agriculture. The agricultural activity is not a token cover crop. It is a real production system that contributes to farm income, livestock operations, or ecological services like pollinator support.

The distinction matters because a conventional utility-scale solar farm covers the ground in gravel or sterile soil and produces zero agricultural output. Once that land is contracted to a solar lease for 25 to 30 years, the productive ag use is effectively suspended. Agrivoltaics is the design philosophy that keeps both uses live on the same dirt.

In California, agrivoltaics is increasingly treated as a separate policy category from utility-scale solar, with different permitting paths, different incentive eligibility, and different treatment under agricultural land protection laws.

Why Agrivoltaics Matters in 2026

California has set some of the most aggressive renewable generation targets in the country, with SB 100 calling for 100 percent zero-carbon electricity by 2045 and intermediate targets pulling forward billions of dollars of new solar build through the late 2020s. The state needs land. Lots of it.

At the same time, agricultural land economics have shifted hard. Inland farmland in Riverside, Imperial, and Kern counties trades anywhere from a few thousand to $20,000 per acre depending on water rights, soil, and zoning, while suburban land within commuting distance of Los Angeles, San Diego, or Orange County easily exceeds $100,000 per acre and rises into seven figures near urban cores.

That price gap is the structural reason solar developers target ag land for new generation. It is also the reason ag landowners now have real leverage to negotiate dual-use designs rather than sign land over for single-use solar farms.

Layer in California's groundwater restrictions under the Sustainable Groundwater Management Act, which is forcing thousands of acres in the southern San Joaquin Valley out of irrigated production, and you have a perfect storm. Land that can no longer support intensive irrigated row crops can sometimes still support dryland grazing, pollinator habitat, or low-water specialty crops, all of which pair naturally with solar.

The Three Main Agrivoltaic Models

Three approaches dominate California agrivoltaic projects in 2026. Each one has a different structural cost, a different match to specific crops or livestock, and a different revenue profile.

Model 1: Elevated panels over row crops

Panels are mounted on tall racking, typically 8 to 14 feet of clearance, over rows of vegetables, lettuce, leafy greens, or other shade-tolerant specialty crops. The elevated structure allows tractors, harvesters, and irrigation equipment to operate underneath. Crop selection is driven by partial shade tolerance, because rows directly under the panels can receive 30 to 50 percent less direct sunlight depending on panel spacing.

UC Davis, Jacks Solar Garden in Colorado, and the InSPIRE research network funded by the U.S. Department of Energy have documented strong results with lettuces, chard, kale, peppers, tomatoes, and many herbs under elevated solar. Hot-climate research from the University of Arizona at Biosphere 2 has shown some crops actually produce more biomass under partial shade than in full sun, because the shade reduces heat stress and evapotranspiration.

Model 2: Sheep grazing under fixed-tilt solar

This is the most common agrivoltaic model in California by acreage. Standard fixed-tilt or single-axis tracking solar is installed at conventional residential or utility heights, typically 3 to 6 feet of clearance to the lower edge of the panel. Sheep graze the vegetation between and under the panels, controlling weeds and reducing fire risk while producing wool and lamb income for the grazing operator.

The American Solar Grazing Association maintains a registry of solar grazing contractors. In California, established flocks operate across the San Joaquin Valley, Sacramento Valley, and Central Coast. For inland Southern California ranchers, sheep grazing under panels is a natural extension of existing dryland grazing operations.

Model 3: Pollinator habitat and bee corridors

Native wildflower and pollinator-friendly seed mixes are planted under and around the array. The land produces zero direct agricultural revenue but supports honeybee colonies, native bees, and other pollinators that benefit adjacent farms. Many California developers now offer a pollinator option as part of their environmental mitigation package, and a growing number of corporate offtake buyers prefer pollinator-friendly solar in their ESG reporting.

A fourth emerging model worth flagging is solar over greenhouse and shade-house structures, in which the solar array becomes the shade element for protected cultivation. Strawberry, ornamental, and nursery operations across coastal California are starting to test this configuration. The capital cost is higher than ground-mount solar but the agricultural return per acre is also far higher, which makes the combined ROI competitive for high-value specialty crops.

Vineyard Solar and Temecula Wine Country

Temecula Valley AVA growers ask about solar more than almost any other ag question, and the honest answer has nuance. Direct overhead canopies on premium wine grape blocks are still considered experimental, and the consensus from research at Washington State University in the Snake River AVA and at trials in southern France is that full shading reduces ripening, sugar accumulation, and color development for varietals that depend on heat units.

That said, Temecula vineyards have multiple non-vine surfaces that pair beautifully with solar:

• Winery production buildings and barrel storage roofs
• Tasting room and event pavilion roofs
• Pump houses and well infrastructure
• Equipment yards and crush pad shade structures
• Employee parking and visitor parking solar carports
• Irrigation reservoir floating solar in limited cases

Several Temecula wineries have already installed substantial rooftop solar on their production facilities, offsetting refrigeration, crush, and bottling loads. The ROI is strong because winery electrical loads peak in late summer and early fall, exactly when solar production is at its highest.

Targeted experimental blocks with partial shade structures are being trialed at a handful of California wineries, particularly for white varietals and for emerging climate-adaptation varietals being tested as our growing season shifts. If you want to experiment, designate a single block, instrument it for sugar and pH tracking, and treat it as a research investment rather than a production decision.

Williamson Act, Solar Use Easements, and SB 618

California's Williamson Act, formally the California Land Conservation Act of 1965, gives landowners a substantial property tax reduction in exchange for a 10-year rolling contract to keep their land in agricultural use. Roughly half of California's farmland is enrolled. The intersection with solar has been a source of confusion for two decades.

The short version for landowners:

• On-site solar that powers the farm operation itself is generally treated as a compatible use under the Williamson Act and does not trigger non-renewal.
• A solar lease to a third-party developer for utility-scale generation on prime productive farmland can trigger a finding that the land is no longer in qualifying agricultural use, which leads to non-renewal and eventual loss of the tax benefit.
• SB 618, signed into law in 2011 and refined in subsequent legislation, created the Solar Use Easement under Government Code section 51191. This allows marginally productive or impaired farmland to be rescinded from Williamson Act status and converted to solar use without the standard non-renewal penalty, provided the land meets defined impairment criteria.
• Agrivoltaic projects that keep the land in genuine agricultural production typically maintain Williamson Act eligibility, though each county has its own assessor practice and you should always confirm in writing.

Riverside County's Agricultural Commissioner and Assessor have published guidance on solar and Williamson Act compliance. Anyone considering a solar lease on Williamson Act contracted land should request a pre-application determination in writing before signing any developer agreement.

Federal IRA Bonus Credits and Tax Incentives

The federal Inflation Reduction Act of 2022 expanded the Investment Tax Credit for solar to a base of 30 percent through 2032, with several stacking bonus credits that apply specifically to agricultural and rural projects:

• Domestic content bonus: An additional 10 percent if the project uses qualifying domestic-manufactured panels, racking, and steel.
• Energy community bonus: An additional 10 percent for projects in qualifying energy communities, which include census tracts with retired coal or fossil generation and high unemployment in the energy sector.
• Low-income community bonus: Up to an additional 10 to 20 percent for projects that serve qualifying low-income communities or tribal lands.
• Prevailing wage and apprenticeship requirements: Projects above 1 megawatt that do not meet prevailing wage and registered apprenticeship requirements drop from a 30 percent base to a 6 percent base. For ag-scale projects this is a major consideration that often pushes landowners to use developers who specialize in these compliance programs.

USDA's Rural Energy for America Program (REAP) provides grants and loan guarantees specifically for agricultural producers and rural small businesses installing renewable energy. Many California family farms have used REAP grants to cover 25 to 50 percent of solar project costs on their own land.

California also maintains the Solar Property Tax Exclusion, which exempts the added value of qualifying solar improvements from property tax reassessment if installed before January 1, 2027. Legislation has been introduced multiple times to extend this exemption further, but the current sunset is real and matters for project timing decisions.

WDAT vs NEMA: Choosing the Right Interconnection Path

One of the most consequential decisions for a farm-scale solar project is which interconnection tariff it uses. The two relevant categories for most California agricultural landowners are WDAT and NEMA.

WDAT, Wholesale Distribution Access Tariff

This is the path for systems that produce more power than the farm consumes on-site, where the surplus is sold into the wholesale market through the local utility distribution system. WDAT is typically used by projects of 1 megawatt or larger that have a power purchase agreement with the utility or a third-party offtaker. The interconnection study process is multi-year, the queue position can take 24 to 48 months to advance, and grid upgrade costs can range from negligible to deal-killing depending on the distribution feeder.

NEMA, Net Energy Metering Aggregation

NEMA is the retail-side option that suits the vast majority of working family farms in California. A single solar system, ground-mount or rooftop, can offset the bills of multiple service meters on contiguous parcels owned by the same agricultural operator. The well pump on the back pasture, the residence, the barn, and the irrigation pivots all aggregate under one NEMA account. Under the current NEM 3.0 successor tariff rules, NEMA still preserves meaningful value for agricultural operations that consume most of their solar output on-site, especially when combined with battery storage to time-shift production to evening pump cycles.

Sheep Grazing Economics Under California Solar

Sheep grazing has emerged as the workhorse of California agrivoltaics for one straightforward reason: the math favors it over mechanical vegetation management on almost every site.

Standard mechanical mowing under a fixed-tilt solar array runs $25 to $50 per acre per visit in California, and most sites need three to five visits per year to maintain fire clearance and prevent vegetation from shading panels. Add string trimming around posts, herbicide costs, and the fire ignition risk from any internal combustion engine operating in dry California vegetation, and the total annual cost easily reaches $150 to $300 per acre.

Contract sheep grazing typically runs $1 to $3 per acre per year in net cost to the solar site owner, because the grazing contractor captures revenue from wool, lamb, and the value of the forage itself. Some grazing contracts have the solar site owner pay the grazier, some are revenue-neutral with the grazier paying a small lease fee, and some are net-positive for the site owner depending on forage quality and stocking density.

For the rancher with an existing flock, agrivoltaic grazing is a way to extend the grazing season, reduce truck miles between pastures, and lock in a stable forage base. Several Central Valley and Central Coast sheep operations have built their business model entirely around solar grazing contracts.

The agronomic side of solar grazing is also more sophisticated than it looks from the road. Stocking rates have to match available forage and panel geometry, water access has to be planned around the array layout, and lambing schedules have to avoid the months when site work or panel washing is planned. Experienced graziers use rotational paddock systems within the solar site, moving sheep between sections of the array on a 7 to 21 day cycle to give vegetation time to regrow.

Cattle and goats are sometimes proposed as alternatives to sheep, but neither has caught on at scale in California. Cattle are too tall and too heavy, and they bump and lean on racking in ways that damage panels and create maintenance costs. Goats will climb anything climbable, including panels, racking, and inverter pads, and they strip bark from any tree or shrub used for screening. Sheep stay below panel height, ignore the structure, and prefer grass to woody vegetation.

For inland Riverside County ranchers running dryland sheep on parcels in Anza, Aguanga, or the rolling country east of Temecula, solar grazing is the most natural ag-energy pairing available. The forage species, the climate, and the existing operational model all line up.

Pollinator Solar Economics

Pollinator solar produces no direct agricultural revenue from the seeded habitat itself, but it carries three other forms of value. First, native wildflower seed mixes can dramatically reduce long-term vegetation management costs once established, because deep-rooted native perennials suppress invasive weeds and require less mowing than annual grass cover.

Second, pollinator habitat near orchard or row crop operations measurably benefits adjacent agriculture. UC Davis and Xerces Society research has shown yield increases of 5 to 30 percent on pollinator-dependent crops within a half-mile of high-quality habitat. For a solar developer leasing land adjacent to an almond or stone-fruit orchard, the pollinator option becomes a real selling point with the neighbor.

Third, ESG-driven corporate offtakers and renewable energy buyers now actively prefer pollinator-friendly solar in their procurement scoring. Several major California utilities and corporate buyers have published preferred-supplier criteria that include pollinator habitat. For a developer, that translates into stronger offtake terms and easier permitting.

California Case Studies and Research Sites

Several active California sites are producing real-world data that landowners can reference when evaluating their own options:

• UC Davis agrivoltaic research site: Multi-year trials on row crops, forages, and pollinator habitat under elevated panels. Publicly available datasets and annual research reports.
• San Joaquin Valley sheep grazing operations: Several hundred megawatts of fixed-tilt solar across Fresno, Tulare, Kern, and Kings counties are actively grazed by contract flocks.
• Jacks Solar Garden, Colorado: Out of state, but the most thoroughly documented commercial agrivoltaic site in the western United States, with publicly available production data on vegetables under elevated panels.
• Washington State University Snake River AVA vineyard solar trials: Multi-year wine grape research under partial shade structures, with results that California vintners watch closely.
• Biosphere 2, University of Arizona: Hot-arid climate research showing crop yield benefits under partial solar shade for several specialty vegetables in conditions similar to inland Southern California.

The American Solar Grazing Association, the AG Solar Coalition, and the InSPIRE network funded by NREL all publish California-relevant resources and connect landowners with experienced practitioners.

Water Savings Under Solar Panels

One of the more striking findings from agrivoltaic research is the consistent reduction in crop water demand under elevated solar arrays. Across multiple sites in Arizona, Colorado, Oregon, and California, researchers have measured reductions in evapotranspiration of 14 to 30 percent on crops grown in partial shade under panels.

The mechanism is straightforward. Direct sunlight on bare soil and leaf surfaces drives evaporation and transpiration. Partial shade reduces leaf temperature, reduces vapor pressure deficit, and reduces total water loss. In hot inland California conditions, the effect is most pronounced during the July through September period when irrigation demand peaks.

For a farm under SGMA water allocation pressure, that 14 to 30 percent water savings on a portion of the crop area can be the difference between staying in production and fallowing acreage. The effect is well documented for lettuces, leafy greens, peppers, tomatoes, and herbs. Tree crops such as avocado and citrus, the dominant ag products in De Luz and the foothills, have less published research on in-canopy water effects under panels.

Riverside County Permit Pathway

Permitting agrivoltaics in Riverside County depends heavily on parcel zoning, system size, and the level of agricultural co-use. A few key checkpoints for landowners:

• Zoning: Most working farms and ranches sit in A-1, A-2, or W-2 zones. Solar is generally a conditionally permitted use, meaning a Conditional Use Permit is required above certain size thresholds.
• Size thresholds: Small on-farm systems sized to meet on-site load and interconnected under NEMA are typically reviewed ministerially. Systems above 1 megawatt or that exceed a defined percentage of the parcel typically require a CUP and CEQA review.
• Setbacks and screening: Riverside County requires specific setbacks from property lines, public roads, and adjacent residences. Visual screening with vegetation or fencing is often required at parcel edges visible from public roads.
• Williamson Act: If the parcel is under contract, the assessor must determine compatibility. For genuine agrivoltaic dual-use designs, compatibility is usually findable, but it has to be documented.
• Area Plans: Riverside County is divided into multiple Area Plans with different policies. The Temecula Valley Area Plan, the Southwest Area Plan, and the Eastern Coachella Valley Area Plan each have different language on solar.

The single most important step is a pre-application meeting with the Riverside County Planning Department before commissioning engineering. A 30-minute pre-app meeting can save six months of redesign work later.

Lease the Land or Own the System

The fundamental financial structuring choice for landowners is whether to lease land to a developer or to own the solar system directly.

Leasing to a developer

The developer designs, finances, builds, and operates the system. The landowner receives a fixed annual lease payment per acre, typically $800 to $2,000 per acre per year in inland Southern California, with annual escalators of 1.5 to 2.5 percent. The lease term is usually 20 to 30 years with extension options. The developer handles interconnection, permitting, insurance, and decommissioning. The landowner takes no construction risk and no operational risk.

The trade-off is loss of control. The developer chooses the design, sets the panel layout, and determines the level of agricultural co-use. Negotiating genuine agrivoltaic terms into the lease, rather than accepting a standard utility-scale single-use design, requires legal support and strong upfront leverage.

Owning the system

The landowner is the project owner. Higher per-acre economics, full control over design and agricultural integration, full claim on ITC and any USDA REAP grants, and full ownership of long-term revenue. The cost is capital, operational complexity, interconnection risk, and direct exposure to equipment degradation and curtailment.

For most working family farms with reasonable on-site electrical load, a NEMA-interconnected self-owned system in the 100 kilowatt to 1 megawatt range usually beats a developer lease on an apples-to-apples NPV basis, and keeps the landowner in operational control. For idle marginal land that the farm cannot productively use, a developer lease can be the more practical choice.

A third middle path is the joint venture or revenue-share structure, where the landowner contributes the land and the developer contributes the system, financing, and operating expertise, and the two parties split production revenue or net cash flow on an agreed schedule. These structures are more complex to document and they require an experienced solar attorney, but they let landowners participate in the upside of higher energy prices without taking on construction risk.

Whichever path a landowner chooses, three contract terms deserve careful attention: the decommissioning bond or surety to ensure the system is removed at end of life, the surface-use protections that govern the agricultural co-use throughout the lease, and the assignment clause that controls who the developer can transfer the lease to. Many landowners have signed leases with a familiar local developer only to see the lease assigned to a distant private equity owner within five years, with very different priorities around agricultural co-use.

How to Evaluate Your Property

Before any conversation with a developer or installer, a landowner can do a quick self-assessment using six criteria:

1. Slope. Flat to gently sloped parcels under 10 percent grade are ideal. Steeper terrain requires terracing or specialized racking and quickly becomes uneconomic.
2. Sun exposure. Unobstructed southern exposure is best. Heavy tree canopy, ridgelines that cast morning or evening shade, and east-facing slopes all reduce yield.
3. Soil and drainage. Soils that support pier or post foundations without major remediation are preferred. Expansive clays, heavy rock, and high groundwater all add cost.
4. Distance to interconnection. The closer the parcel is to a 3-phase distribution line or a substation, the lower the interconnection cost. Long line extensions can add hundreds of thousands of dollars to project cost.
5. Current and planned ag use. What crop or livestock operation runs on the parcel today? Which agrivoltaic model is the natural fit? Sheep grazing fits dryland pasture, elevated panels fit row crops, pollinator habitat fits land transitioning out of intensive use.
6. Zoning and contract status. What zone is the parcel in? Is it under a Williamson Act contract, a Solar Use Easement, or a conservation easement? What does the county Area Plan say about solar?

A parcel that scores well on five or six of these criteria is a strong agrivoltaic candidate. A parcel that scores well on two or three is worth a more careful look. A parcel that scores well on zero or one is probably better suited to other uses than solar.

For specific Riverside County parcels in Temecula Wine Country, De Luz, Anza, Aguanga, and the Murrieta horse country, local terrain and adjacency to existing distribution infrastructure both matter. A De Luz avocado grove sitting on a south-facing slope with a 3-phase line at the road is a very different proposition than a north-facing Anza parcel three miles from the nearest power pole.

Murrieta horse properties present a distinct subset of the local agrivoltaic question. Many of these parcels are between 2.5 and 20 acres, zoned for limited equestrian use, with significant existing infrastructure for arenas, barns, and pastures. Rooftop solar on barns and shade structures over outdoor arenas can offset substantial electrical load from well pumps, lighting, and ventilation, while leaving the pasture surface untouched. Ground-mount solar on unused acreage at the back of the parcel is also a viable option for owners who want to support the operation with on-site generation.

De Luz parcels are dominated by avocado and citrus on steep terrain, and the agrivoltaic question there is almost always about the support buildings, packing sheds, and well infrastructure rather than the orchard canopy itself. Anza and Aguanga properties tend toward larger acreages, lower land values, and dryland or limited-irrigation use, which makes them well suited to sheep grazing under fixed-tilt solar if interconnection capacity is reachable.

Across all of these submarkets, the single biggest determinant of project feasibility is interconnection. SCE's hosting capacity maps, available on the utility website, show real-time available distribution capacity at the feeder level. Parcels near constrained feeders face long interconnection studies and large upgrade costs. Parcels near healthy feeders move quickly. Anyone serious about an agrivoltaic project should pull the hosting capacity map early in the evaluation process.

Frequently Asked Questions