What Does a Solar Inverter Do?
It turns the direct current your panels make into the alternating current your home and the grid use — and runs the system while it does it: finding each moment’s best operating point, matching the grid, reporting production and switching off within two seconds when the grid goes down. In Los Angeles in 2025, 42% of new solar homes on SCE used microinverters, 34% a Tesla unit — almost all a Powerwall 3 doing double duty as battery and inverter — and 17% SolarEdge’s optimizer system.
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- Five jobs: DC-to-AC conversion, maximum power point tracking, grid synchronization and support, monitoring, and shutting off when the grid fails.
- What LA installs: microinverters 42%, Tesla 34% (mostly Powerwall 3 as a hybrid inverter), SolarEdge 17%, everything else 7%.
- Efficiency is no longer the differentiator: listed microinverters run a median 96.5% weighted efficiency, other inverters 97%.
- It is the part most likely to need replacing: warranties run 10–12 years for string inverters and 25 for Enphase microinverters.
What an inverter does
Converts DC to AC
Panels make direct current; power electronics switch it thousands of times a second into 60 Hz alternating current at your home’s 240 V.
Finds the best operating point
Maximum power point tracking (MPPT) keeps adjusting voltage and current as sun and temperature change, to pull the most power from the panels.
Works with the grid
It matches grid voltage and frequency, and California “smart” inverters can also help steady the grid — riding through brief disturbances and adjusting output to support voltage (DOE).
Shuts off in an outage
A grid-tied inverter must disconnect within two seconds when the grid goes down (SCE Rule 21), so it cannot energize lines crews are working on. Only a battery with backup equipment keeps the house running.
Most also report production and faults to an app, and many support a battery. See how solar panels work and solar in a power outage.
The types, and what LA homes chose in 2025
| Type | How it works | Share | Main example |
|---|---|---|---|
| Microinverters | A small inverter under every panel, each with its own MPPT | 42.2% | Enphase IQ8 series |
| Hybrid (battery + inverter) | One unit takes DC from panels and battery and makes AC | 31.1% | Tesla Powerwall 3 |
| String inverter with optimizers | A DC optimizer on each panel feeds one inverter on the wall | 17.2% | SolarEdge HD-Wave |
| Other string or hybrid inverters | One wall-mounted inverter for strings of panels, with or without a battery input | 9.5% | Various brands |
Source: CPUC DG Stats, 16,118 residential systems approved in 2025 in SCE’s part of Los Angeles County, by first listed inverter; Powerwall 3 identified by Tesla part number 1707000 (Tesla warranty). Cali Energy count; LADWP is not in this dataset.
The Powerwall 3 counts as an inverter because it has one built in: it takes up to 20 kW of solar DC directly and delivers up to 11.5 kW AC (datasheet). Microinverters and optimizers both manage each panel separately, which helps on shaded or multi-plane roofs; for a head-to-head on one Northridge roof, see Enphase vs SolarEdge, and for shade, solar, shade and trees.
Efficiency and certification
| Models | Weighted efficiency (middle 80%) | Median | |
|---|---|---|---|
| Microinverters | 577 | 96.0–97.0% | 96.5% |
| String, hybrid and other | 1,610 | 96.0–98.5% | 97.0% |
Source: CEC Grid Support Solar Inverter List (unchanged since October 1, 2026); microinverters identified by description. Cali Energy count.
A percentage point of inverter efficiency matters less than it used to; layout, shade and sizing decide more. Of the 2,187 listed models, 859 (39%) are hybrid — able to take DC from both panels and a battery — and 1,431 (65%) carry UL 1741 Supplement SB certification, the newest test for “smart” grid-support functions. The CEC notes that utilities and permitting agencies set which functions they require, so the installer should confirm the model meets your utility’s definition.
Inverter sizing: why the panels are often bigger
Panels rarely reach their full rating on a real roof, so inverters are often a little smaller than the array. The median DC-to-AC ratio on 2025 LA systems was 1.09 — for example, 8.3 kW of panels on a 7.6 kW inverter (DG Stats). On the brightest hours the inverter caps output (“clipping”); in one Northridge comparison that cost 0.6% to 2.5% of a year’s energy depending on the equipment. See Enphase vs SolarEdge.
How long inverters last
The inverter is usually the first major part to need replacing. Enphase covers its microinverters for 25 years (warranty); SolarEdge covers its inverters for 12 years, the Nexis line for 10 (warranty); both exclude on-site labor. NREL’s residential cost model budgets 1.6% of microinverter capacity a year for out-of-warranty repair or replacement, against 0.2% for panels. A Powerwall 3 is covered by Tesla’s 10-year warranty. See inverter replacement and solar warranties explained.
Choosing one
Shade or several roof planes
Panel-level electronics — microinverters or optimizers — keep one shaded panel from dragging down the rest.
Battery now or later
A hybrid inverter takes the battery directly; microinverter systems add an AC-coupled battery. See adding a battery and Powerwall 3 vs Enphase vs FranklinWH.
Where it lives
Microinverters sit under the panels; a string or hybrid inverter hangs on a wall where it is easy to reach and replace.
Warranty and labor
Compare the years and who pays the crew for a swap.
Where to go next
Cali Energy installs microinverter, optimizer and hybrid systems in Los Angeles and can match one to your roof and battery plans. Call +1-323-844-7777 or ask which fits your home — production figures are estimates, not guarantees. See also grid-tied vs off-grid vs hybrid.
Frequently asked
What does a solar inverter do?
It converts the panels’ direct current into the alternating current your home and the grid use, tracks the panels’ best operating point, synchronizes with the grid, reports production, and disconnects within two seconds when the grid goes down.
What are the types of solar inverters?
Microinverters (one per panel), string inverters (one for many panels, often with per-panel optimizers) and hybrid inverters that also connect a battery. In 2025, new LA County homes on SCE used microinverters 42% of the time, a Tesla Powerwall 3 as a hybrid inverter 31%, and SolarEdge optimizer systems 17%.
Which inverter is best for a shaded roof?
One with panel-level electronics: microinverters or a string inverter with optimizers, so a shaded panel does not pull down the others.
How efficient are solar inverters?
Very: on the California Energy Commission’s list, microinverters have a median weighted efficiency of 96.5% and other inverters 97%, with the middle 80% between 96% and 98.5%.
Do I need a special inverter to add a battery?
Not necessarily. A hybrid inverter accepts the battery directly; otherwise an AC-coupled battery brings its own inverter and works alongside the existing one.
Does a solar inverter work during a power outage?
A grid-tied inverter shuts off within two seconds of an outage. A hybrid inverter or battery with backup equipment can keep backed-up circuits running.
How long does a solar inverter last?
Warranties are 10–12 years for SolarEdge inverters, 25 years for Enphase microinverters and 10 for a Powerwall 3; the inverter is usually the first major part to need replacing.
Related reading
Sources & methodology
Figures on this page come from the primary sources below and, where noted, from Cali Energy calculations using the stated assumptions. Rates, incentives, and program terms change; each was verified October 5, 2026.
- California Energy Commission — Grid Support Solar Inverter List (efficiency, hybrid, UL 1741 SB; data as of October 1, 2026)
- California DG Stats — Interconnected Project Sites (SCE, data through August 31, 2026; Cali Energy count for Los Angeles County)
- U.S. Department of Energy — Solar Integration: Inverters and Grid Services Basics
- SCE — Rule 21, Generating Facility Interconnections (anti-islanding, two seconds)
- Tesla — Powerwall 3 datasheet (20 kW DC solar input, 11.5 kW AC)
- Tesla — Powerwall Limited Warranty (USA), Rev. 2.6 (part numbers, 10 years)
- Enphase — US Limited Warranty, IQ Microinverters (effective May 2, 2026)
- SolarEdge — Limited Product Warranty (effective January 1, 2026)
- NREL — Q1-2025 Solar PV System Cost Benchmarks, residential model (inverter replacement rate)
Match the inverter to your roof and goals
Get an inverter chosen for your shading, roof layout and battery plans. Estimates, not guarantees.
Get a free estimatePrepared by Cali Energy, October 5, 2026. This article is for general educational purposes only and is not legal, tax, financial, engineering, or utility advice. Rates, incentives, codes, permit requirements, equipment specifications, prices, and program terms may change; figures and timelines are estimates, not guarantees. Confirm current requirements with the applicable utility, AHJ, program administrator, manufacturer, or a licensed professional. See our Content Disclaimer. Cali Energy · 19201 Parthenia St, Unit E, Northridge, CA 91324 · CSLB #1032379 (B, C-10, C-39)