Solar panels in Ontario
Ontario owns a utility company, which confuses people every time. It does not sell you electricity. Power in Ontario comes from Southern California Edison, and that one fact sets the economics of every solar panel system in the city: Edison customers fall under the state's Net Billing Tariff, the rules most people call NEM 3.0. A system designed for those rules looks different from one designed for a city-run program. Collective Solar has designed and serviced solar since 2010, from our office in Northridge, and we work across the Inland Empire.
Why Ontario is a net billing city, not a municipal one
The Ontario Municipal Utilities Company is real and it is city-owned, but it delivers water and wastewater. It does not deliver power. Electric service in Ontario is Southern California Edison, and gas is SoCalGas. Because Edison is an investor-owned utility, it answers to the California Public Utilities Commission — so the municipal solar programs you may have read about in cities like Burbank or Glendale have nothing to do with your bill here.
What applies instead is the Net Billing Tariff. The CPUC adopted it in December 2022 under Decision 22-12-056, and it covers every customer who submitted an interconnection application on or after April 15, 2023. Under net billing, the power you send back to the grid is credited at the grid's avoided cost — a value that changes by hour and by month — rather than at the retail rate you pay. It is not one number, so nobody should quote you one. We will show you how your own usage lines up against those export values before you sign anything.
So the sizing question in Ontario is not how many panels fit on the roof. It is how much of its own production the house can absorb while the sun is still on it. A kilowatt-hour used the moment your array makes it offsets the full retail rate. The same kilowatt-hour handed to Edison earns whatever that particular hour is worth to the grid, which is normally a good deal less. Timing is what makes this bite here. Edison's residential time-of-use plans price the late-afternoon and evening block above every other hour of the day, and on the common plan that block runs 4 p.m. to 9 p.m. on weekdays — which in Ontario is exactly when the house is still working against a hot inland afternoon and the array has already started to fade. Storage is what bridges those hours. It does not bridge them profitably in every home, so we run your usage with a battery and without one and hand you both sets of numbers.
Before you take a quote from anyone, check how it treats the federal credit. Section 25D — the 30% credit a homeowner claimed on a system they bought outright — expired December 31, 2025 and cannot be claimed on a residential project in 2026. A quote that still shows it is either out of date or padding the savings. Third-party ownership sits on different footing, because the incentive follows whoever owns the equipment rather than the person on the roof. Our guide to the solar tax credit in 2026 and our lease-vs-buy comparison set out what that changes about repairs, monitoring and selling the house later.
Three Ontarios, three different solar jobs
Old Ontario runs along Euclid Avenue and the streets around downtown — the double boulevard with the planted center parkway that George and William Chaffey laid out as the spine of the colony, and which now carries a National Register listing. The housing beside it is Craftsman bungalow, Victorian, Mission and Period Revival. On stock that age the roof sets the schedule, not the array: composition shingle with eight years left in it has no business carrying panels warranted for twenty-five, so the roof gets assessed first and we will tell you to reroof before we will sell you a system. Where the panels are already up and the roof underneath has run out, our panel removal and reinstall service lifts the array, lets the roofers work, and sets it back.
Then there is the postwar tract stock. Ontario went from about 23,000 people in 1950 to roughly 47,000 in 1960 and 64,000 by 1970, and the ranch homes from that build-out are straightforward solar territory: simple gable roofs, open sun, almost no shade. The catch is underneath. Main service panels from that era were sized for a house with one air conditioner and nothing plugged into the garage wall, so on plenty of these addresses the panel, not the roof, is the limit. When it is, an electrical panel upgrade belongs in the same scope and the same permit, priced up front — not raised as a change order once the array is already on the roof.
Ontario Ranch — south of Riverside Drive, between Euclid and Milliken, running down to the Eastvale line — is a different problem entirely. It is roughly 8,000 acres building out toward something near 47,000 homes, and anything completed after January 1, 2020 arrived with panels on it, because the 2019 Title 24 energy code made photovoltaics standard on new low-rise housing. Two things follow from that. The array was sized for the house as the builder handed it over, so an EV, a pool pump, a converted garage office or two more people in the household can outgrow it fast. And the system may not be yours: builder solar is sometimes bought outright, sometimes carried on a lease or a power purchase agreement, and only the paperwork tells you which. Bring it. We add capacity to builder systems, retrofit storage, and diagnose underperformance through our solar repair service — the equipment does not have to be something we sold you.
Every new solar installation in Ontario permits through the city's own building division inside Community Development — not San Bernardino County. Since August 4, 2025 the city has run an automated permitting platform through Symbium for residential roof-mounted solar and storage under 38.4 kW, plus detached single-family re-roofs, and it issues plan-review approval on the spot for projects that qualify. That part is genuinely fast. The on-site inspection still has to happen, and the permit is only half the job: interconnection is a separate application to Edison under the CPUC's Rule 21, and the system stays switched off until Edison grants permission to operate. We prepare and file the city package and the interconnection package, and we chase both.
Warehouse roofs are Ontario's biggest solar opportunity
The city publishes the numbers on its own logistics and distribution page: roughly 120 million square feet of industrial space, some 240 logistics establishments, a 4.6% industrial vacancy rate, and more than 750,000 tons of air cargo a year through Ontario International Airport. The density clusters around The HUB at the airport, LogistiCenter at Ontario Ranch, and the Safari Business Center off Vineyard.
A distribution building is close to an ideal solar host. The roof is flat, unshaded, and measured in acres. More to the point, the load in a building like that generally runs in daylight — packaged rooftop HVAC and evaporative cooling, refrigeration wherever there is cold storage, conveyor and sortation lines, air compressors, and increasingly forklift and yard-truck charging. Net billing rewards exactly that shape. When a building consumes most of what its roof makes in real time, the low export credit barely matters: you are offsetting retail power rather than selling into the grid. Your own interval data is what settles it, and Edison can release that for your meter.
The federal picture splits by property type, and the calendar now matters as much as the credit. The residential purchase credit is gone. The commercial 48E investment tax credit is still available to business-owned systems in 2026 — but under the 2025 tax law, a solar project that did not begin construction by July 4, 2026 has to be placed in service by December 31, 2027 to claim it. On a roof this size that is a schedule, not a formality, so sequencing belongs at the front of the conversation and the credit itself belongs in front of your tax advisor. The other questions worth asking early: who owns the roof, how much roof warranty is left, and whether the structure takes the added load. Start with our commercial solar page or our commercial solar breakdown for the Los Angeles market, then request a building assessment.
We cover the neighboring Inland Empire cities too, and the first thing we check at each address is who bills it. Most of Rancho Cucamonga to the north is Edison, but the city runs its own utility over a pocket in the southeast. Fontana to the east is Edison throughout. Corona, across the Riverside County line, is mostly Edison with a few areas on the city's own department. Ontario is the simple case — Edison citywide — but we never assume a neighboring address inherits it.
Ontario solar questions
Who provides electricity in Ontario, CA?
Southern California Edison. The Ontario Municipal Utilities Company is city-owned but provides water and wastewater service only, not power. Because Edison is an investor-owned utility regulated by the California Public Utilities Commission, new solar in Ontario goes on the state's Net Billing Tariff rather than a city-run solar program like the ones in Burbank or Glendale.
Does NEM 3.0 apply to solar in Ontario?
Yes. The program's formal name is the Net Billing Tariff. The CPUC adopted it in December 2022 under Decision 22-12-056, and it applies to customers who submitted an interconnection application on or after April 15, 2023. Exported power is credited at the grid's avoided cost, which varies by hour and month, instead of the retail rate. That is why we design Ontario systems around what you use on site rather than around maximum export.
My Ontario Ranch home already came with solar. Can you still help?
Yes, and it is a common call. Homes completed after January 1, 2020 came with photovoltaics because the 2019 Title 24 energy code required them, sized for the house as the builder delivered it. Some of those systems were bought with the home and some are on a builder lease or a power purchase agreement, and the paperwork is the only reliable way to tell. We add capacity, retrofit batteries, and diagnose underperforming builder systems. Bring the original agreement to the consultation and we will read it with you before recommending anything.
Who issues solar permits in Ontario?
The City of Ontario's building division, inside Community Development — not San Bernardino County. Since August 4, 2025 the city has used an automated Symbium portal that issues plan-review approval on the spot for qualifying residential roof-mounted solar and storage under 38.4 kW, along with detached single-family re-roofs. Physical inspection still applies. Interconnection is separate: Edison reviews it under the CPUC's Rule 21, and the system has to stay off until Edison grants permission to operate. We prepare and file the permit and the interconnection paperwork and follow both through.
Is there still a federal tax credit for solar on an Ontario warehouse?
For a business-owned system, yes, and the timing is the part to watch. The 48E investment tax credit is still available in 2026, but under the 2025 federal tax law a solar project that did not begin construction by July 4, 2026 has to be placed in service by December 31, 2027 to claim it. That is a real constraint on a large roof, so the schedule needs planning early. The residential side is different: the homeowner credit under Section 25D expired December 31, 2025 and cannot be claimed on a 2026 home project. We are not tax advisors, so confirm how either rule applies to your situation with yours.
Get a free solar estimate for your Ontario property
A Euclid Avenue bungalow, an Ontario Ranch builder array, or a distribution roof near the airport. We size it around what Edison actually credits, and we show you the arithmetic.