Agricultural solar in California, built around your pumps — not a brochure.
Well pumps, boosters, frost protection, cold storage and processing loads run on a schedule set by the crop and the weather — not by PG&E's rate calendar. Solar doesn't erase that tension, but sized against your real interval data it changes the math. Here's what's actually true for California ag solar right now: the tariffs, the multi-meter aggregation rules, the Williamson Act, and a property-tax clock most growers haven't heard about.
Three numbers that shape every ag solar decision.
PG&E's restructured Schedule AG bills you on measured demand with a peak window that no longer matches the sun. The state's aggregation rules still let one array serve all your meters — under different economics than the ones your neighbor locked in years ago. And the property-tax exclusion that keeps a new array from raising your assessment is on a statutory clock.
PG&E's agricultural peak window — 365 days a year. No seasonal exemption, no partial-peak. It sits mostly after solar hours, which is why honest ag proposals talk about self-consumption and load-shifting, not "free daytime pumping."
The Section 73 property-tax exclusion deadline. Systems completed before this date don't trigger a new-construction reassessment. The legislature has not renewed it further — this is the most time-sensitive fact on this page.
Per-project cap on CDFA's SWEEP grant, which explicitly funds converting irrigation pumps to solar. The 2026 round has closed; the next one routes through your local Resource Conservation District.
PG&E's agricultural rate structure, honestly explained.
Since March 2021, agricultural customers bill under a restructured Schedule AG — most operations land on AG-A1, AG-A2, AG-B or AG-C depending on load size. The legacy AG-1/AG-4/AG-5 schedules longtime customers remember are gone. Two changes matter most for solar planning:
- Peak pricing runs 5pm–8pm every day of the year — not just summer afternoons. There is no partial-peak period and no seasonal exemption.
- Billing is based on actual measured demand, not a flat estimate tied to connected horsepower. A short, hard start on a large pump can set your demand charge for the month.
- AG-C carries a demand-charge limiter — the only tier with spike protection — worth reviewing if your operation has large motor starts.
Here's the nuance most ag solar pitches skip: because the 5–8pm peak window falls mostly after strong production hours, solar alone will not fully dodge the peak-period penalty. What it does well is offset the bulk of your daytime kWh, and — if pumping can shift into mid-day production hours — reduce the demand charge that peak measured load creates. Whether a battery to carry load into the evening window pencils is a site-specific question your interval data answers, not a checkbox on a proposal.
One array, all your meters: aggregation still works — differently.
Many operations run several PG&E meters across one property or adjacent parcels — a home meter, a shop meter, two or three pump meters. Since 2012, Net Energy Metering Aggregation has let one array's credits offset load across all of them, provided the meters sit on the same, adjacent, or contiguous property.
That mechanism still exists for new applicants in 2026 — but the compensation underneath it changed. Since February 2024, new applications are processed under Solar Billing Plan Aggregation: exported energy is credited at the state's avoided-cost rate rather than the older retail-rate credit, and industry estimates put current export value at roughly a quarter of what NEM 2.0 paid.
What that means in practice: aggregation across your pump meters is still worth using, but the strategy shifted. Instead of oversizing an array to bank surplus export value, the better approach today is sizing close to your combined on-site consumption — self-consuming what you generate rather than counting on export credits. If you hold a legacy NEM 1.0/2.0 aggregation agreement, you keep those terms for the balance of the 20-year contract; only new applications fall under the new economics.
Which incentives are genuinely open right now.
The federal 30% credit (Section 48E, December 31, 2027 placed-in-service deadline for new projects) and permanent 100% bonus depreciation apply to farm-owned systems like any other business — covered in full here, along with the REAP grant pause (guaranteed loans remain open). Beyond those, here's the ag-specific picture:
- SGIP storage incentives: effectively closed to ag. The General Market budget — the category a commercial or agricultural battery would use — closed to new applications December 31, 2025, and the only category still taking waitlisted applications is residential and income-qualified. Budgets do periodically get reauthorized, so we re-check before every proposal — but nobody should be selling you a battery on promised SGIP dollars today.
- SWEEP: real, solar-eligible, and between rounds. CDFA's State Water Efficiency and Enhancement Program explicitly funds pump conversion to solar — plus variable-frequency drives, drip conversion, and irrigation scheduling — reimbursing up to $200,000 per project. The 2026 concept-proposal window closed in mid-May, and applications now route through regional Resource Conservation Districts rather than the state directly. If SWEEP fits your project, the move is getting on your local RCD's list for the next round.
- REAP guaranteed loans: open. The USDA guarantee improves the terms a lender will offer, and it stacks with the federal credit and depreciation. Rural eligibility reaches more of the Central Valley, Sacramento Valley and foothills than most owners assume.
Williamson Act land: possible, but it's a formal process.
If some of your acreage is enrolled under the Land Conservation Act, solar on that ground isn't automatically off the table — and it isn't a simple permit either. Since 2011, state law has allowed solar-use easements on Williamson Act land: a landowner can carve out an easement for solar, subject to Department of Conservation eligibility review, without necessarily terminating the agricultural preserve contract on the rest of the parcel.
A bill in the legislature — AB 1156 — would make this considerably easier, letting the contract be suspended for the easement's term rather than rescinded, and adding battery storage to the authorized uses. As of this writing it has not passed; it was moved to the inactive file in September 2025 and remains pending. Don't plan around rules that don't exist yet — today's process is the existing framework, and it runs on its own timeline through your county and the Department of Conservation, separate from interconnection and financing.
Roof, ground, or carport — and what's real about the exotic options.
| Roof / barn-mount | Ground-mount | Carport over equipment yard | |
|---|---|---|---|
| Best for | Packing sheds, barns, shops with sound roofs | Open acreage, marginal or non-cropped ground | Equipment yards, truck staging, employee parking |
| Typical size | Small–medium | Medium–large | Medium |
| Land-use tradeoff | None — uses existing structure | Takes acreage out of production, or needs non-crop ground; Williamson Act review if on preserve land | None — dual-use of already-graded area |
| Structural checks | Roof age, load capacity, orientation | Soil and foundation work | Foundations, clearance for vehicles |
| Section 73 exclusion | Applies — deadline-sensitive | Applies — deadline-sensitive | Applies — deadline-sensitive |
| Added site value | — | Grazing/dual-use worth discussing | Shade and weather protection for equipment |
Solar over canals is real — and not for sale yet. California's Project Nexus pilot on Turlock Irrigation District canals is complete and operating, with early monitoring showing meaningful reductions in evaporation and weed growth under the panels. But it's a state-funded research pilot on the district's own infrastructure, not a product an individual grower can order. Worth watching; not something anyone can build for you today, and we won't pretend otherwise.
Agrivoltaics — grazing or cropping around panels — is documented mostly at utility scale in California (sheep under Central Valley solar farms). At farm scale, sheep for vegetation management under your own ground-mount is a reasonable option to discuss during design; it's a site decision, not a packaged program.
The property-tax exclusion sunsets January 1, 2027.
Revenue and Taxation Code Section 73 excludes a new active solar energy system from triggering a property-tax reassessment as new construction. Without it, a new ground-mount array could raise your assessed value. The legislature has not renewed the exclusion further: it currently applies only to systems completed before January 1, 2027. Systems already under construction before January 1, 2026 have some additional room to finish during 2026; projects that haven't broken ground face a tight runway.
Once qualified, the exclusion generally isn't tied to who owns the system and stays in place until the property itself changes hands. Given typical timelines — design, permitting, interconnection, construction — a farm that wants this treatment locked in should be moving now, not next spring. We also recommend confirming specifics with your county assessor, since Williamson Act-restricted parcels already carry non-standard valuation.
Agricultural solar FAQ.
Does solar actually reduce my PG&E demand charges, or just my energy usage?
Both are possible, but it depends on your load profile. Solar directly offsets the kilowatt-hours you consume during daylight hours. Demand charges are driven by your peak measured load in a billing interval, so solar only reduces them if your peak demand overlaps with solar production — which is why we review your actual interval data before sizing a system, rather than assuming solar will flatten every demand spike.
Can one solar array serve multiple meters on my property?
Often yes, through Net Energy Metering Aggregation — one system's credits offsetting load across meters on the same, adjacent, or contiguous property. The common case: a home meter plus one or more irrigation pump meters. New applications run under the current Solar Billing Plan Aggregation framework, which pays exported energy at avoided-cost rates rather than NEM 2.0's retail credit — so sizing for self-consumption matters more than it used to. Details above.
Is REAP still funding agricultural solar projects?
USDA REAP grants are paused for new applications as of this writing; REAP guaranteed loans remain open, and the guarantee genuinely improves lender terms. Federal status changes periodically — we check it as part of every ag proposal. More on our commercial solar page.
Will putting solar on my land affect my Williamson Act contract?
It can, but a legal pathway exists: a solar-use easement, available since 2011, lets solar sit on enrolled land without necessarily terminating the underlying contract, subject to Department of Conservation review. A bill to ease this (AB 1156) is pending but has not passed — today's more involved framework is what applies. Start with your county and likely legal counsel before finalizing any design on preserve land.
Is there a deadline to avoid a property tax increase from installing solar?
Yes — the Section 73 exclusion currently applies only to systems completed before January 1, 2027, and the legislature has not renewed it further. Given typical project timelines, a farm that wants this protection should be moving on a project now. See the property-tax section.
Can I graze animals or farm around my solar panels?
It's a documented practice — most visibly sheep grazing for vegetation management at utility-scale Central Valley solar farms. At farm scale it's a site-specific design decision rather than an off-the-shelf program; happy to discuss it during design if it fits your operation.
What about solar over my irrigation canals?
California's Project Nexus pilot on Turlock Irrigation District canals proved the concept — real reductions in evaporation and weed growth under the panels — but it's a state-funded research project on the district's own infrastructure, not a product an individual grower can order today. We'll tell you if and when that changes.
Are there state grants that specifically fund solar for irrigation pumps?
CDFA's SWEEP program is the closest fit — it explicitly funds pump conversion to solar, plus variable-frequency drives, drip conversion and irrigation scheduling, reimbursing up to $200,000 per project. The 2026 round has closed, and applications now route through local Resource Conservation Districts — get on your RCD's list for the next round.
Talk to someone who reads interval data, not brochures.
Get an agricultural assessmentEvery farm's power bill tells a different story — crop, pump count, meter layout, and whether any ground is under Williamson Act contract. We'll review your actual PG&E interval data and rate schedule, walk the aggregation options across your meters, and give you a straight answer on what's achievable — including which incentives are genuinely open versus paused or closed. Want the broader picture first? See our commercial solar overview or how the financing structures compare. Or call 1-800-815-9358.