We live in Concord. Most of the systems we design are within a fifteen-minute drive of our own roof. So when someone asks what solar costs here, we can answer with the number we actually use — not a national average scraped off an aggregator site.
This post gives you the price, the arithmetic behind it, and the parts of a quote that are easy to get wrong. There is no federal residential tax credit in that arithmetic, because there isn’t one any more.
What does a typical Concord solar system cost in 2026?
We plan at $2,800 per kW installed. That is the figure in our own savings calculator, and it is the figure we quote from. It covers panels, inverters, racking, electrical work, permitting and inspection for a standard composition-shingle roof.
| System size | Installed price at $2,800/kW |
|—|—|
| 4 kW | $11,200 |
| 5 kW | $14,000 |
| 6 kW | $16,800 |
| 7 kW | $19,600 |
| 8 kW | $22,400 |
| 10 kW | $28,000 |
A battery adds roughly $15,000 on top. That is a real adder, not a rounding error, and it is why we ask what a battery is for before we price one in.
Here is what that turns into for a specific household. A Concord home on a $220-a-month PG&E bill needs about 4.5 kW — around $12,600 installed. Our calculator puts that at roughly $1,105 a year saved, about 42% of the bill, an 11.4-year payback, and about $19,760 net over 25 years after allowing for a $3,000 mid-life inverter replacement.
Forty-two percent. Not ninety. Not “eliminate your bill.” Two things cap it:
- Contra Costa roofs produce about 1,500 kWh per kW per year. That is good — it is not Arizona.
- PG&E’s $24-a-month Base Services Charge cannot be offset by solar generation credits. PG&E says so in plain English on its own billing page. On a $220 bill the arithmetic ceiling for any system, of any size, is `(220 − 24) / 220` — about 89%. On a $150 bill it is 84%. We wrote up what the base charge does to solar savings separately.
Across the homes we design in Contra Costa, a solar-only system typically lands at 40–55% of the bill, and 55–75% with a battery. If someone shows you a proposal promising more than that in PG&E territory in 2026, ask them to show you the base charge line.
Why is the average system in Concord smaller than in Walnut Creek?
Third-party solar aggregator pages that publish per-city market averages list roughly 6.96 kW for Concord against roughly 9.91 kW for Walnut Creek. We can’t independently audit either number — they’re someone else’s data — but the direction matches exactly what we see on the ground, and the reasons are worth understanding because they apply to your house too.
Housing stock. A lot of Concord is 1950s–70s single-storey ranch: modest square footage, composition-shingle roofs, generous south-facing planes. Easy to work on, and the house doesn’t demand much. Walnut Creek runs to larger, later, better-insulated homes — bigger footprint, bigger load, bigger system.
Load, not roof area. System size follows consumption, not available roof. A 1,400-square-foot Concord ranch with a gas furnace and no pool simply does not use what a 3,200-square-foot Northgate home with air conditioning, a pool pump and two EVs uses.
Shading. Walnut Creek has heavy tree cover in parts, so shading studies matter more there and per-panel optimisers or micro-inverters earn their place. Concord’s flatter, more open lots need less of that.
The practical point: a bigger system is not a better system. Under net billing, exported power earns a fraction of what you pay for imported power, so kilowatts you build and don’t use yourself are close to wasted money. We size to your usage. If your neighbour’s system is bigger than the one we propose, that is usually because their bill is bigger.
What’s included in the price, and what gets quoted separately?
Included at $2,800/kW:
- Panels, inverters or micro-inverters, and racking
- Electrical work up to and including the interconnection
- Structural and electrical engineering, and the plan set
- Permit application and fees, and the inspection
- The PG&E interconnection application
Quoted separately, every time:
- Battery storage — about $15,000, and only if there’s a reason for it.
- Roof work. If your roof has under about ten years left, it should be replaced before an array goes on it. Taking a system down and re-mounting it later costs more than doing the roof first. We will tell you this even when it delays the job.
- Main panel upgrade. Older Concord homes on 100-amp service often need one. It is a real electrical job with its own permit.
- Tile or shake roofing. Different mounting hardware and a slower install. More common in Danville and Blackhawk than here, but Concord has some.
- Ground mount, trenching, tree removal, structural reinforcement. All site-specific.
- De-rate or re-work on an unusual service entrance.
If a quote gives you one number and no line items, ask for the breakdown. A price that can’t be decomposed usually can’t be defended.
One more line to expect: California’s active solar property tax exclusion sunsets on 1 January 2027. AB 2389, which would have extended it, died on the Assembly Appropriations suspense file in May 2026. We are not going to predict whether the Legislature revives it. We are telling you the sunset date because it is a real date on the calendar and it belongs in your decision.
How do cash, loan, lease and PPA compare now the 25D credit is gone?
The federal Section 25D residential credit expired on 31 December 2025. If you buy a system for your own home with cash or a loan in 2026, there is no 30% federal credit. Any installer’s website still showing one is out of date — check the dates on their page.
Cash. Lowest lifetime cost, full ownership, no interest, no lien, nothing to transfer when you sell. On the 4.5 kW example above, our calculator’s 11.4-year payback and ~$19,760 net over 25 years are cash figures.
Loan. You keep ownership, and you spread the cost. The thing to watch is the dealer fee — the amount a lender charges the installer to offer a low advertised rate, which is then built into the system price. It is real, it is often large, and it is rarely labelled. The way to see it: ask for the cash price and the financed price side by side, in writing. The gap is the fee. Then judge the loan on that gap, not on the headline APR.
Lease and PPA. You do not own the system; a third party does. Because the provider owns it, the provider — not you — may be able to claim a federal credit under the commercial regime, and that is generally reflected in the rate you’re offered. What you take on in exchange is a long contract, usually with an annual price escalator, that has to be dealt with when you sell the house. Read the escalator clause and the transfer clause before anything else. We don’t say leases are wrong; we say most people sign them without reading those two clauses.
Whichever route you take, two documents are legally required with a residential solar contract in California: the CPUC’s California Solar Consumer Protection Guide and the CSLB’s Solar Energy System Disclosure Document. If you didn’t get both, something is off. And under Business & Professions Code §7159 you have three business days to cancel a home improvement contract — five business days if the buyer is 65 or older.
What makes one quote cheaper than another — and when should that worry you?
Sometimes a lower price is just a leaner business. Sometimes it is a cost that hasn’t been priced yet. These are the differences worth chasing:
Legitimate reasons a quote is cheaper
- Smaller system, correctly sized to your actual usage
- Simpler roof — one plane, one orientation, easy access
- No main panel upgrade needed
- String inverter instead of micro-inverters, on a roof with no shading
- Lower-tier panels with shorter warranty terms — a real trade-off, honestly made
Reasons to slow down
- The roof isn’t in the price. The cheapest quote on a 22-year-old roof is the most expensive one.
- The main panel upgrade isn’t in the price. Ask directly whether your service can carry the system.
- The offset claim is above the arithmetic ceiling. Anything near 100% in PG&E territory ignores the $24 base charge.
- Production assumptions above about 1,500 kWh/kW/year for Contra Costa without a site-specific shading study to justify them.
- A cash price you can’t get in writing alongside the financed price.
- A price that expires today. Solar equipment pricing does not move hourly. A deadline on a quote is a sales tactic, not a market condition.
- No CSLB licence number on the paperwork. Check it at cslb.ca.gov before you sign anything.
To be clear about how we work: we design the system and project-manage the job — engineering, permitting, interconnection, inspection, scheduling. Licensed contractor partners do the physical installation. Between us, Navjot and Nam bring over a decade of California solar experience to that design and management work. We would rather say that plainly than let you assume something else.
Nearby, the pattern holds. In Richmond the Chauhan family’s 4.44 kW rooftop system went from paperwork to finished in 63 days. In Hercules, the Khawaja family’s system was 7.65 kW. Different houses, different sizes, because different bills.
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Want your own number rather than an average?
Put your actual PG&E bill into our savings calculator. It uses every figure in this post — $24 base charge, 36¢/kWh, 1,500 kWh/kW/year, $2,800/kW, no federal credit — so what it shows you is what we’d show you.
If you’d like a person to look at it with you, book a free consultation. No pressure, no same-day discount, and if the numbers don’t work for your house we will say so. You can also read more about how we approach residential systems or whether solar is still worth it in Contra Costa in 2026.
Rates and rules verified 30 August 2026.