Solar Panel Installation in Rohnert Park

The billing rule that decides how your system should be designed

The compensation rule is the part that changes what we should build for you, and it changed for everyone who has gone solar since spring of 2023.

The California Public Utilities Commission adopted the Net Billing Tariff in December 2022, applying to customers who submitted an interconnection application on or after April 15, 2023. The CPUC states that under net billing, "compensation for excess generation exported to the electric grid is applied to a customer's bill at a rate reflecting the value of this generation to the grid," using Avoided Cost Calculator values the commission itself notes are "usually lower than import rates." Under the older NEM 2.0 arrangement, exports were credited at retail import rates instead.

Rohnert Park sits in Sonoma Clean Power territory, so the local expression is SCP's Solar Billing Plan. It covers systems whose PG&E Permission to Operate was completed after April 14, 2023, plus former net metering customers whose twenty-year plans have ended. SCP's description of how credits work is the sentence to read twice: "The credit amount changes depending on the day of the year, time of day, and season." Credits run highest during high-demand periods, and SCP points at the window from 4 p.m. to 9 p.m. as the stretch where exported energy is worth most. Surplus is cashed out each spring at the Net Surplus Compensation rate, subject to an annual cap. SCP's older NetGreen net metering program is closed to new customers.

Now put that against the local climate. This is inland Sonoma County, west of the coastal fog and hot through summer afternoons, and cooling carries real load here in a way it does not in Sausalito or Bolinas. A Rohnert Park house draws hardest on air conditioning through late afternoon and early evening, the same window in which exported energy is worth the most and imported energy costs the most.

That collision is the design argument on this side of the county. An array with no storage produces its bulk at midday, when the house is often empty and the export credit is weakest, then contributes nothing at 6 p.m. when the condenser is running and the rate peaks. This is not a claim that batteries are universally correct. It is a statement that in a hot inland city on a time-differentiated tariff, the array and the battery are one design question rather than two purchases.

Size for the house you are going to have

A system sized to last year's bill is sized for a house that is about to change, and in Rohnert Park the direction of that change is already written into regulation.

Rohnert Park sits fully inside the Bay Area Air Quality Management District. Sonoma County publishes the district boundaries, and they matter: northern county towns like Cloverdale and Healdsburg fall under a different district entirely, while Rohnert Park, Cotati, and Penngrove are fully inside BAAQMD. Its Rule 9-6 is a point of sale rule, phasing standards in by appliance across 2027 and 2031. In practice that means an electric heat pump unit. Nobody's gas water heater is being confiscated, and we confirm the requirement in force at the time of your project.

The relevance to solar is arithmetic. A heat pump water heater adds a 240-volt load. So does an electric vehicle, and so does a heat pump replacing a gas furnace, which comes up constantly here because the original ducted systems from the build era are aging out together. If two or three of those are likely within the life of the array, size for that house and plan the panel work once instead of three times.

What a defensible production estimate contains

Production numbers are the easiest part of a solar proposal to inflate.

Orientation and tilt set the ceiling. South-facing planes produce the most annual energy; west-facing planes produce less annually but produce it later in the day, which under a time-differentiated tariff is worth more per unit than it used to be. That is a genuine shift from how arrays were laid out under old net metering, when a kilowatt-hour was a kilowatt-hour whenever it arrived.

Shading is measured, not eyeballed. Rohnert Park's street trees are decades into their growth, and a tree that clears a roof today may not in five years. A real model accounts for what shades the roof in December at 3 p.m., not only in June at noon. Where shading is unavoidable, module-level electronics keep one shaded module from dragging a whole string; on a clean tract roof that case is weaker and the money may go further toward capacity.

Fire code roof access pathways and setbacks consume usable area, so a proposal that fills the roof plane edge to edge has not been through plan check. Ask any installer, including us, which planes the model used and what it assumed about shading. If the answer is a regional average, the number is decoration.

What drives the cost of a solar project in Rohnert Park

We do not publish flat prices, because the same array on two houses in the same section can be two different jobs. What moves the number:

System size, driven by usage, usable roof area after access pathways, and whether you are sizing for present load or an electrified house.

Roof condition, material, and complexity. Composition shingle in good condition is the straightforward case. Tile, a roof needing work first, multiple planes, and heavy vent penetrations all mean more labor and less usable area.

The electrical work. Existing panel, supply-side connection, or new equipment. This is the largest single swing on a build-era house.

Storage. Usable capacity, how many circuits are backed up, and whether backup covers essentials or most of the house.

Anything outside the automated lane. Ground mounts and carports carry structural and trenching work and take the conventional permit path.

Permit fees, which state law constrains in your favor. Under Government Code section 65850.55, a jurisdiction may not "base the calculation of the fee on the valuation of the solar energy system, or any other factor not directly associated with the cost to issue the permit," and it "shall separately identify each fee assessed." Your fee is tied to the cost of issuing the permit, not the size of your investment.

Nothing is open-ended: the cost is fixed first, and financing is available.

The sequence, from design to Permission to Operate

Design and site assessment come first: roof condition, shading, usage history, panel capacity. The permit follows, through the city's automated platform for a qualifying rooftop system or through eTRAKiT for everything else. Properties in the unincorporated county surrounding the city permit through Permit Sonoma instead. Installation on a straightforward tract roof is typically a short stretch of days, then the single inspection state law allows.

Then comes the part nobody controls: PG&E interconnection and Permission to Operate. Your system is not authorized to produce for the grid until PTO is granted, and that date matters beyond paperwork, because SCP's Solar Billing Plan keys to it. Interconnection queues stretch through spring and summer as the season's projects stack up, so an off-season start is the easiest way to shorten your calendar. We handle the permit, the inspection, and the interconnection filing as part of the job.

Rebates, incentives, and what is on the table

The incentive picture for solar in Sonoma County is thinner than the internet suggests, and being clear about that is more useful than a list of expired programs.

The compensation mechanism, not a rebate. Your ongoing economics come from SCP's Solar Billing Plan, which sets what exports are worth by hour and season. Design the system to fit it.

Sonoma Clean Power's remaining rebates sit on the appliance side, mainly heat pump water heating, rather than on the array itself.

We confirm what your project qualifies for when we quote it rather than promising a credit that may not survive to your install date.

Maintenance and what goes wrong

Rooftop solar is low-maintenance, not no-maintenance, and the failures are predictable.

Monitoring is the whole maintenance program in one habit. Check production monthly against the same month last year. A gradual decline is usually soiling or a tree that has grown. A sudden drop is usually a tripped inverter, a failed optimizer, or a communications fault. Modules rarely fail; electronics and connections do.

Cleaning is mostly the rain's job here, and the return on routine washing is small. If you do rinse, do it early or late so water does not dry on hot glass, and never walk an array. Trim encroaching branches before they reach the array, not after production has dropped.

Batteries need exercising. Test backup twice a year so an actual outage is not the first time you learn which circuits are on it and how long they last. Roof penetrations deserve a look whenever the roof is inspected, since the flashing at each mount is the interface between your array and your building envelope.

Where we work in Rohnert Park

We serve all of Rohnert Park from our Petaluma headquarters, straight up 101. That covers the planned sections on both sides of the freeway, the neighborhoods around Sonoma State University, and surrounding unincorporated properties that permit through Permit Sonoma rather than the city. Neighboring Cotati and Penngrove sit in the same air district and the same Sonoma Clean Power territory, so the design logic here applies there too. Petaluma is our home rather than a satellite branch, and our crews know Rohnert Park's housing stock the way they know Petaluma's east side.

How to choose a solar company in Rohnert Park

California gives homeowners more protection on solar contracts than on almost any other home improvement, and most people never use it. Use it.

Check the contract's cover page. Business and Professions Code section 7169 requires the state's solar energy system disclosure document to be "printed on the front page or cover page of every solar energy contract," in boldface 16-point type, covering total cost, payment terms, complaint procedures, and cancellation rights. It also requires that the contract and disclosure be "written in the same language as was principally used in the oral sales presentation made to the consumer." If that document is not on the front of the contract, the contract does not comply with California law, and that tells you something before you read a single technical spec.

Check the license classification. The Contractors State License Board maintains both a C-46 Solar and a C-10 Electrical classification, and its license lookup will show what a company holds and whether it is in good standing. Ask, then verify it yourself. Ongaro & Sons holds a C-10 electrical license along with C-20 HVAC and C-36 plumbing, and carries a BBB A+ rating and Diamond Certified status.

Ask whether your project fits the automated permit lane. A company working here regularly should know immediately whether your system qualifies or has to go through eTRAKiT, and what that does to your timeline.

Ask what the production model assumed, and whether it came from your usage history or a regional average. If nobody has looked at your roof, nobody has modeled your roof.

Ask about the panel before you sign. If a proposal has not addressed your service capacity and interconnection method, the price is provisional and you have not been told so. And get in writing who owns the roof penetrations, and for how long.

None of that has changed since 1932: see the house, describe the finding plainly, put the number in writing first, and build it to code.

Solar, electrical, and home services across Rohnert Park and Sonoma County

One company, all trades: solar across Sonoma County, Rohnert Park home services, Rohnert Park electrical, Rohnert Park heating and cooling, and Rohnert Park plumbing. Related Rohnert Park services that pair with a solar project: electrical panel upgrades, EV charger installation, heat pump systems, and water heater replacement. Nearby solar work: Petaluma and Santa Rosa.