How solar actually works on a California home

Key takeaways

Solar panels convert sunlight to DC electricity. An inverter converts it to AC for your house, and excess production feeds back to the grid through your utility meter.

A typical California residential system has five parts: panels, inverter(s), racking, a monitoring system, and the utility interconnection.

In 2026, new solar systems on SCE, PG&E, and SDG&E run under NEM 3.0. LADWP still uses 1:1 net metering. The rules change the math, not the physics.

Most California installs take 8 to 14 weeks from contract to power-on. Actual timelines vary by utility and jurisdiction.

Solar panels typically produce for 30+ years, though the performance warranty floor is usually 25 years at 80 to 92% of original output depending on brand.

If you're thinking about going solar and you've been Googling "how do solar panels work," most of the articles you'll find explain photons knocking electrons loose in a silicon cell and then stop there. That's the physics. It's not the part that actually matters when you're deciding whether to put panels on your roof. What matters is how the whole system runs on your house, how it talks to SCE or LADWP, what happens during an outage, and what it takes to go from "interested" to "powered on." We're a licensed California contractor and we install these systems every week. This guide walks through solar the way we'd explain it if you called us for a free estimate and asked "OK, but how does this actually work?"

The short version: sun goes in, AC power comes out

A residential solar system has one job. Capture sunlight on your roof, convert it to electricity your house can use, and sell anything you don't use back to your utility. That's it. The complexity is in how each of those three jobs gets done and what hardware makes it happen. Once you understand the five main components, the rest of the conversation — cost, payback, batteries, interconnection — gets a lot easier.

The five parts of a home solar system

Every residential solar installation in California has these five components. Different installers use different brands, but the architecture is the same.

1. Solar panels

The big rectangles on your roof. Each panel contains silicon photovoltaic (PV) cells that convert sunlight into direct-current (DC) electricity. A typical 2026 residential panel is rated at 400 to 460 watts. Most California homes need 12 to 28 panels depending on your annual energy use. Panel brands commonly used in California include REC, JA Solar, Silfab, Qcells, and Hyundai. Panel efficiency typically runs 20 to 22.5%, which means that percentage of sunlight hitting the panel gets converted to electricity. The rest becomes heat.

2. Inverter(s)

Your house runs on alternating current (AC). Panels produce DC. Something has to convert between the two, and that's the inverter. There are three styles. String/Central inverters (one box handling all panels on a shared circuit — "string" and "central" refer to the same basic concept at residential scale, sometimes used interchangeably). Microinverters (Enphase) sit behind each panel and convert DC to AC right there on the roof. Power optimizers (SolarEdge) sit behind each panel but send the DC to a central inverter. Most new California installs in 2026 use Enphase IQ8X microinverters because one shaded or underperforming panel doesn't drag down the whole system.

3. Racking and mounting

The aluminum rails that bolt to your roof and hold the panels up. Most residential systems use flush-mount racking that keeps panels a few inches off the roof surface for cooling. On tile roofs we use tile replacement hooks; on shingle roofs, flashed mounting feet. This is where roofing expertise matters. If a solar company doesn't understand your roof, the racking either leaks in five years or doesn't meet wind load engineering.

4. Monitoring system

A small device (Enphase IQ Gateway, SolarEdge monitoring module, Tesla Gateway) connects your inverter to the internet so you can see production data through an app. Panel-level monitoring lets you spot a dead panel at year 6 before it drags down production. System-level monitoring just shows total output. We always recommend panel-level when it's available.

5. The utility interconnection

This is the part most articles skip. Your solar has to be formally connected to the grid with utility approval ("Permission to Operate," or PTO). That involves a new bidirectional meter that reads both what you pull from the grid and what you push back. It involves the utility approving your plans, your installed system, and your net-metering enrollment. This is the step that takes weeks, not minutes.

How solar connects to your house and the grid

Here's the actual path electricity takes when your solar is running. Understanding this makes NEM 3.0 and LADWP net metering make sense.

During the day, when your panels are producing

Sunlight hits your panels. Panels produce DC electricity. The inverter converts it to 240-volt AC that matches your household wiring. That AC power feeds into your main electrical panel (the one in your garage with the breakers). From there, it powers everything in your house that's currently drawing: refrigerator, TV, lights, AC, whatever. If your panels are producing more than your house is using, the excess flows backward through your electric meter to the grid. Your meter spins backward (on mechanical meters) or records exports (on digital smart meters).

At night and on cloudy days

Panels don't produce at night. Your house still needs power. So you pull AC electricity from the grid through the same meter that was exporting earlier. The meter records what you buy. Net metering is the accounting layer that compares what you sent vs. what you bought and decides what you owe.

The bill-accounting layer: NEM 3.0 vs NEM 2.0 vs LADWP 1:1

This is where the utility makes a huge difference. Under the old NEM 2.0 (pre-April 2023), your exports credited at roughly retail rate. Sell at 35 cents, buy at 35 cents. Under NEM 3.0 (current rules for SCE, PG&E, SDG&E), exports credit at the avoided-cost rate of about 5 to 8 cents. You still buy at 35 to 45 cents. That's why batteries matter under NEM 3.0. On LADWP, 1:1 net metering still applies in 2026, so the math is closer to the old NEM 2.0 world. Same physics, different accounting.

What happens during a power outage

This is one of the most common misunderstandings. A standard grid-tied solar system, without a battery, shuts down the moment the utility grid goes down. This is for the safety of utility line workers, who can't have your panels energizing the wires they're repairing. Solar alone is not backup power.

To have power during an outage, you need a battery

A battery storage system adds two things: a battery (Tesla Powerwall 3, Enphase IQ Battery 10C) and a gateway or system controller. The gateway detects when the grid drops, isolates your house from the grid (for line-worker safety), and lets your solar keep running to power your house and recharge the battery during daylight. During the night of an outage, the battery carries you.

What to expect from installation: the 8 to 14-week journey

From signed contract to powered-on solar, most California residential installs land between 8 and 14 weeks. Utility timelines vary — some process interconnection faster than others, but each has its own quirks and potential holdups. Here's the phase-by-phase walkthrough of how we run these projects, which is very similar to how most licensed California installers do it.

Phase	Timeline	What happens
Site visit	Week 1	We walk your roof, look at your electrical panel, pull your last 12 months of utility data, and quote the system.
Design & contract	Weeks 1–2	Final system design, panel layout, equipment selection, contract signing. Permit package gets drafted.
Permitting	Weeks 2–6	City plan check. Most jurisdictions take 2–6 weeks. Timeline varies — check with your installer on your specific city's current pace.
Installation	Weeks 5–7	Physical install: mounting, panels, inverter, wiring. Typically 1–3 days on site for residential.
Inspection	Weeks 6–8	City inspector signs off. Sometimes a revisit if something isn't flush to code.
Interconnection & power-on	Weeks 7–14	Utility reviews the signed-off system and issues Permission to Operate (PTO). Then you turn it on. Green Conception splits this process to save time: the first half of the interconnection application is submitted with your permit plans, and the second half goes in after we pass inspection. Most installers wait until after inspection to submit anything — our approach cuts weeks off the total timeline.

We've documented the specifics of our process on the from site inspection to installation page. Most of the 8 to 14 week window isn't waiting on us. It's waiting on permits, inspections, and the utility.

What solar costs in California in 2026

A fully installed residential solar system in California in 2026 runs about $3.00 to $4.50 per watt before financing. For a typical 7 kW system (the most common size), that's $21,000 to $31,500.

On financing: in 2026, California homeowners have three main paths — cash purchase, a solar loan, or a lease. Cash gives you the best long-term return. A loan lets you own the system from day one and pay over time. A lease means the installer owns the panels — you pay a monthly rate with zero upfront, but you won't own the system, which matters when you sell the home. For a full breakdown of the finance math on each option, see our 

solar economics page.

Frequently asked questions

Do solar panels work on cloudy days?

Yes, but at reduced output. On a heavily overcast day you might see 10 to 25% of your typical clear-sky production; on a lightly overcast or hazy day the output can stay as high as 50%. On a rainy day, even less. California's climate is favorable for solar specifically because we have a lot of clear sunny days and relatively few stretches of dense overcast.

Do solar panels work when it's hot?

They work, but they lose efficiency as they heat up. Every panel has a temperature coefficient, typically -0.25% to -0.35% per degree Celsius above 25°C. On a 100°F California summer day, panel surface temperatures can hit 150°F, which drops output by 10 to 15%. When selecting panels, ask your installer about the temperature coefficient for the specific brand being proposed — it's one of the more meaningful real-world performance specs for Southern California conditions.

Do I need to clean my solar panels?

Not usually. Rain does most of the work. In low-rainfall areas like the Antelope Valley or dusty foothills, an annual hose-down helps. We don't recommend walking on your roof to do it; if you want panels cleaned, hire a professional solar cleaner. Panel cleaning in SoCal runs $15 to $25 per panel.

How long do solar panels last?

Physically, 30 to 40 years is typical. Performance warranty is usually 25 years at 80 to 92% of original output depending on brand. Most panels keep producing usefully into year 30 and beyond. The inverter is usually the first component that needs replacing, typically at year 10 to 15 for string inverters and year 20+ for microinverters.

Does solar increase my home value?

Studies consistently show yes. The Lawrence Berkeley National Laboratory has tracked solar home sales for years and found solar adds roughly $15,000 to $20,000 in appraised value to a typical California home, though this varies by region and system size. Buyers also tend to prefer owned systems over leased ones when deciding what to offer.

What if I sell my house?

If you own the system outright, it transfers with the house. Under NEM 2.0 grandfathering, the tariff transfers to the new owner (what's left of the 20-year term). Leased systems are more complicated; they either transfer to a qualified buyer, get bought out, or get removed. If you're planning to sell within 5 years of install, talk to us about ownership structure before you sign anything.

The bottom line on how solar works

Solar on a California home isn't complicated in theory. Panels make DC, inverters make AC, your house uses some, the grid buys the rest. The complications are in the details: which inverter, which utility, which net metering rules, which permitting jurisdiction, which roof condition. That's why licensed California solar installers earn the contract. If you want us to walk your roof and show you exactly how this would look on your specific house, we'll come out for free, pull your utility data, and write you a quote that explains every line. No upsell games, no pushy calls.

Ready to see what solar would look like on your California home?

We'll walk your roof, pull your last 12 months of utility data, and show you exactly how solar would fit your house, bills, and timeline. No pressure, no commission-driven pitch.

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