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The Golden State Solar Guide

How solar actually works

Watch it, don't just read it. Animated explainers for homeowners and field engineers — from a single photon to a utility power plant.

1

A solar cell turns light into electricity

Sunlight is made of photons. When they strike the silicon in a solar cell, they knock electrons loose. The cell's built-in electric field pushes those electrons one way — and that one-way flow is direct current (DC).

  • Photons in → electrons out through the front contacts.
  • One cell ≈ 0.5 V; ~60–72 cells wired in a module (panel).
  • Output is DC — your home runs on AC, so next comes the inverter.
silicon PV cellloadDC current →
2

The inverter turns DC into AC

Homes and the grid run on alternating current (AC) that flips 60 times a second. An inverter rapidly switches the panel's steady DC back-and-forth and shapes it into a smooth 60 Hz sine wave.

  • Switches (an H-bridge) flip DC polarity thousands of times/sec.
  • Filtering smooths it into a clean sine wave matched to the grid.
  • It also does MPPT — holding panels at their most productive voltage.
DCsteadyINVERTERAC · 60 Hzhome / grid
3

More sun, more power — across the day

A panel's output tracks the sunlight actually hitting it. Generation climbs from sunrise, peaks at solar noon when the sun sits highest, then fades to nothing at night — the familiar solar ‘bell curve’. Watch the sun cross the sky and the output rise with it.

  • Output follows the sun's height in the sky.
  • Peak production lands around midday.
  • Clouds, shade, panel angle and season all reshape the curve.
6 amnoon6 pmpower output
4

Storing sunshine for after dark

Solar peaks at midday, but most homes use the most power in the evening. A home battery banks the daytime surplus and releases it after sunset — so more of your own clean energy runs the house instead of flowing back to the grid.

  • Charges from the midday surplus, discharges at night.
  • Backs up essential circuits during an outage.
  • Turns a daytime resource into round-the-clock power.
surplus → chargehome batteryafter dark → powerhome

Where the inverter lives: 3 configurations

The big design choice. Watch a cloud pass over the middle panel — see which setups lose only one panel, and which lose the whole row.

1 inverteroutput under passing cloud
String inverter

One inverter, panels in series

Cheapest and simplest. But panels share one circuit, so shade or a weak panel drags the whole string down — and you only see one number, not per-panel data.

  • Best for simple, unshaded roofs
  • Lowest cost
  • Whole string affected by shade
Made by: SMA, Fronius, Tesla, Sungrow, GoodWe
+ inverteroutput under passing cloud
Power optimizers

Per-panel DC + one inverter

A small optimizer on each panel (e.g. SolarEdge) tunes it individually, then one inverter converts the lot. Shade hits only the shaded panel; you get panel-level monitoring.

  • Good for some shade / complex roofs
  • Panel-level data
  • Mid cost
Made by: SolarEdge (integrated), Tigo (add-on), Huawei
~~~output under passing cloud
Microinverters

An inverter on every panel

Each panel makes AC on its own (e.g. Enphase). Total independence — shade or a fault on one panel doesn't touch the rest, and there's no single point of failure.

  • Best for shade / complex roofs
  • Panel-level AC + monitoring
  • Highest cost
Made by: Enphase (leader), APsystems, Hoymiles

From a rooftop to a power plant

The same physics scales across three orders of magnitude — what changes is the size and the inverters.

3 – 12 kW

Residential

A handful of rooftop panels feed one string or microinverter, often with a home battery. Single-phase AC powers the house; extra flows to the grid.

  • String or micro inverter
  • Optional home battery
  • Single-phase, net-metered
50 kW – 1 MW

Commercial / business

Big flat roofs, carports and warehouses use rows of panels and several three-phase string inverters to match heavier daytime loads and commercial service.

  • Multiple 3-phase inverters
  • Offsets large daytime load
  • Demand-charge savings
1 MW – 1 GW+

Utility scale

Ground-mounted arrays (often sun-tracking) feed large central or string inverters, step up through a transformer/substation, and push power onto transmission lines.

  • Central or string inverters
  • Transformer + substation
  • Feeds the transmission grid

The data behind the boom

Live, interactive charts from Our World in Data (IEA / IRENA) — hover the lines, press play, or switch countries. This is why solar went from niche to the fastest-growing power source on Earth.

Our World in Data

Prices fell over 99%

Solar module prices collapsed from about $106 per watt in 1976 to well under $0.40 — one of the steepest, most sustained cost declines of any technology in history.

Our World in Data

Wright's Law in action

Every time the world's installed capacity doubles, module prices fall roughly 20%. Scale drives the cost down — and it has held for decades.

Our World in Data

The world keeps building

Cumulative installed solar capacity by country and region, climbing year after year (IRENA).

Our World in Data

Now the cheapest power

Lifetime cost per unit of electricity by source — utility solar is now cheaper than new fossil generation across most of the world.

The hardware: who makes what

Brief, current profiles (researched mid-2025) — every card links to the official site and a live community thread for real owner experience. #1/#2/#3 badges mark US-residential market leaders.

Solar panels

Qcells (Hanwha)Panel#1 leader

Among the most-installed US residential brands, with major American factories (Georgia). Q.TRON / Q.PEAK balance value, quality and a solid warranty.

REC GroupPanel#2

Founded in Norway (1996), now owned by Reliance. The Alpha Pure heterojunction series is high-efficiency with a strong warranty.

Maxeon / SunPowerPanel
SunPower Corp filed Chapter 11 in 2024; the brand was acquired & relaunched.

Highest-efficiency residential panels (~22.8%) with very long warranties; premium price. Spun off from SunPower in 2020.

PanasonicPanel
Exited its NA solar & battery business (announced April 2025).

Long-respected premium panels; honors existing warranties.

Silfab SolarPanel#3

North-American manufacturer (Ontario + WA & SC). High-quality residential modules (~21–22%) — popular where domestic content matters.

JinkoSolarPanel

Among the world's largest makers. Tiger Neo line: dependable performance at competitive prices, widely available.

Canadian SolarPanel

Major global manufacturer (founded 2001). HiKu / HiHero are value-oriented with broad availability.

Trina SolarPanel

Top-ranked for bankability (Wood Mackenzie 2025). Vertex series across residential & utility.

JA SolarPanel

Tier-1 manufacturer, co-top of WoodMac's 2025 ranking. DeepBlue series.

LONGiPanel

World's largest solar manufacturer by capacity. Hi-MO series; heavy R&D.

Inverters & electronics

EnphaseMicroInverter#1 leader

The microinverter leader (~60% of the US residential micro market). IQ8 puts an inverter on every panel — best for shade/complex roofs, panel-level monitoring, battery-ready.

SolarEdgeOptimizerInverter#2

DC optimizers + a string inverter: panel-level optimization & monitoring at lower cost than micros. Large share; navigated 2023–24 financial difficulty.

SMAStringInverter

Sunny Boy string inverters — a reliable workhorse for simpler, unshaded roofs.

FroniusStringInverter

Primo / Symo GEN24 hybrid string inverters — high efficiency, battery-ready, strong monitoring.

TeslaStringInverter#3

Tesla Solar Inverter (string) built to pair with the Powerwall ecosystem & app.

TigoOptimizerInverter

Module-level optimizers + rapid-shutdown that add onto third-party string inverters.

Home batteries

Tesla Powerwall 3Battery#1 leader

13.5 kWh with a built-in solar inverter and high output; cost-effective to expand. Very popular.

Enphase IQ BatteryBattery#2

Modular ~5 kWh units, 15-yr warranty, panel-level ecosystem. Most-used battery by US installers.

FranklinWHBattery#3

aPower (~15 kWh) whole-home backup with generator & EV integration; works with Enphase & SolarEdge.

Generac PWRcellBattery

Modular storage integrating with Generac generators — strong for outage-prone areas.

SolarEdge Home BatteryBattery

DC-coupled battery for SolarEdge systems, single-vendor design & monitoring.

Communities & reviews

For field engineers

Golden State Solar Guide is an independent information resource for Northern California homeowners — not affiliated with PG&E, any utility, or any solar installer. Information here is general and can change; it is not financial, tax, or engineering advice. Verify current programs and get a firm quote from a licensed professional before you decide. Animated explainers are schematic, not to scale. Brand profiles researched mid-2025; verify specs on official sites. Community links are live discussions, not endorsements.
Data: OpenStreetMap, WRI, EIA, IRENA, Global Energy Monitor, Esri imagery.