A generic “cost of solar” number is hard to use when you’re trying to plan an actual budget. A specific system size is easier to work with, and 10 kilowatts happens to be a common target for a mid-size Central Valley home — roughly the range that fits a 2,500 to 3,500 square foot house with a typical PG&E bill. Here’s what a system this size actually costs to install, and what determines whether 10kW is the right fit for your situation in the first place.
What a 10kW System Actually Includes
Ten kilowatts refers to the system’s DC capacity — roughly 24 to 30 panels, depending on the wattage of the specific panels used (modern residential panels typically run 400 to 440 watts each). That capacity number doesn’t include the inverter, mounting hardware, wiring, or labor, which is why “per panel” pricing is a less useful way to think about total cost than price per watt.
A 10kW system is sized to offset a meaningful share of electricity use for a household running a typical mix of HVAC, appliances, and — increasingly — EV charging, but the right size for any specific home depends on actual usage, not a generic square-footage rule.
What a 10kW System Costs Before Any Incentives
The U.S. Department of Energy’s published cost benchmarks put residential solar in a range that generally runs higher per watt than commercial systems, due to smaller project scale and higher relative soft costs (permitting, customer acquisition, and installation labor spread across a smaller system). For a 10,000-watt system, that translates to a wide range depending on your specific roof, electrical panel, and equipment selection — a straightforward installation on a newer roof with adequate electrical capacity will land toward the lower end of the range; a system requiring a roof tear-off, an electrical panel upgrade, or premium equipment (all-black panels, microinverters, integrated battery-ready wiring) will land higher.
Rather than quote a single number that won’t match your specific situation, the more useful exercise is understanding what moves the price: panel brand and efficiency, inverter type (string inverter versus microinverters), roof complexity, and whether your existing electrical panel can handle the added capacity without an upgrade. A written, itemized quote should break out each of these rather than presenting a single lump sum.
Is 10kW the Right Size for Your Home?
Sizing a system correctly matters more than most homeowners realize going in. An undersized system leaves you still paying a meaningful utility bill every month; an oversized system means paying for capacity you’re not using efficiently, especially since California’s net billing tariff pays less for exported excess power than older net metering structures did. The right approach is sizing against your actual annual usage — found on twelve months of utility bills — rather than a square-footage estimate, which is a rough proxy at best.
If you want a rough independent estimate before talking to anyone, the Department of Energy’s PVWatts calculator lets you enter your address and get a production estimate based on your specific roof orientation and local sun hours. It won’t replace an actual site assessment, but it’s a reasonable sanity check on any quote you receive.
What Changed: No Federal Credit for a Purchased System in 2026
Worth stating plainly here, since it changes the math significantly from what older cost guides assume: if you purchase a 10kW system with cash or a loan in 2026, there’s no federal tax credit reducing that cost. The federal Residential Clean Energy Credit ended for any system installed after December 31, 2025.
That doesn’t mean there’s nothing left on the table. California’s property tax exclusion still protects your home’s assessed value from increasing because of the system, and the Self-Generation Incentive Program still offers rebates if you’re pairing the system with battery storage. We’ve broken down what’s actually still available in a separate post on California solar incentives — worth reading before you finalize a budget, since it changes the real out-of-pocket number more than most homeowners expect.
What Still Affects Your Final Number
A few things move a 10kW quote up or down that a generic estimate can’t account for:
- Roof condition and age. If your roof needs replacing within the next several years, it’s worth sequencing that work before installation rather than after.
- Electrical panel capacity. Older homes sometimes need a panel upgrade to safely accommodate the added capacity, which adds cost outside the core solar quote.
- Equipment selection. Premium panels and microinverters cost more upfront but may come with longer warranties or better performance in partial-shade conditions.
- Battery add-on. Pairing the system with storage adds cost but may qualify for SGIP rebates and improves your economics under the current net billing structure.
The only way to get a number you can actually budget against is a site-specific quote that accounts for your roof, your panel, and your actual usage — not a size-based average. Pacific Solar can walk through what a system sized for your home would look like, itemized rather than bundled into one number.
Want a number sized to your actual roof and usage? Get an itemized quote from Pacific Solar instead of a generic estimate.
Frequently Asked Questions
How many panels are actually in a 10kW system? Roughly 24 to 30, depending on the wattage of the specific panels used — most residential panels now run 400 to 440 watts each.
Will a 10kW system cover my whole electric bill? It depends entirely on your actual usage, not the system size in isolation. Sizing against 12 months of utility bills is a far better predictor than a square-footage rule of thumb.
Do I get a tax credit on a 10kW system in 2026? Not for a purchased residential system — the federal credit ended for any system installed after December 31, 2025.
Is it worth adding a battery to a 10kW system? Often, yes, for two reasons: it may qualify for SGIP rebates, and it improves your financial outcome under the current net billing structure compared to exporting excess power for a lower credit.