Quick answer
Microinverter A microinverter is a small inverter mounted behind a single solar panel that converts that panel’s DC output to grid-ready AC on the roof, so each panel works independently of the others.
Shade or a fault on one panel then costs only that panel’s output. The trade-off is more electronics on the roof: one inverter per panel instead of one box on the wall.
Quick facts
The key facts about microinverter, with sources:
- Converts
- One panel’s DC to 240 V split-phase AC (most US homes) 1
- Typical output (one product family)
- 240–380 VA continuous per unit, Enphase IQ8 range 1
- Published CEC efficiency
- 97%–97.5% (Enphase IQ8 family) 1
- Shade behaviour
- Shade on one panel does not reduce the others 3
- Rapid shutdown
- IQ8 listed for NEC 2014–2023 section 690.12 1
- Grid standards
- UL 1741-SA, IEEE 1547:2018 (UL 1741-SB) 1
- Warranty printed (IQ8M/IQ8A)
- Limited warranty of up to 25 years 2
Key takeaways
- A microinverter sits under one panel and turns that panel’s DC into AC.
- Shade or a fault on one panel does not drag down the others.
- Enphase IQ8 units print 97% to 97.5% CEC weighted efficiency.
- On their own they shut off in a blackout. Backup needs a battery and a controller.
- They suit shaded roofs and roofs with several faces. Simple sunny roofs gain less.
- Replacing one means a trip onto the roof.
What a microinverter is
A microinverter is a small inverter clipped to the racking under each panel. The DOE describes microinverters as smaller inverters placed on every panel 3.
Each one does the full inverter job for its own panel. It tracks the panel’s best point, turns its DC into AC, and reports its output. The DOE notes this lets each panel work on its own, which helps when some modules may be shaded 4.
How microinverters work
Each panel plugs into its own microinverter. The unit converts to AC and sends it down a shared AC cable to a breaker in your panel. The DOE notes the main result: shade or damage on one panel does not affect the power from the others 3.
The roof wiring is AC at household voltage, not a high-voltage DC string. So panel count is set by the branch circuit, not a string voltage window. The Enphase IQ8 sheet caps AC protection at 20 A per branch and points to local rules for how many units each branch may carry 1.
Newer units can also form a small grid of their own. Enphase calls IQ8 microgrid-forming. With its IQ System Controller and a battery, it can give backup power and restart from sunlight after a battery runs flat (“Sunlight Jump Start”) 1. Without that gear, a microinverter system still shuts down in an outage.
The path from panel to outlet
- Each panel → its own microinverter → AC at 240 V on the roof
- Shared AC trunk cable → junction box → breaker in your main panel
- Home circuits → meter → grid; the gateway reports each panel’s output
Types in one family: Enphase IQ8 models
| Model | Common panel pairing (W) | MPPT voltage (V) | Max continuous AC (VA) | Peak / CEC efficiency |
|---|---|---|---|---|
| IQ8-60-2-US | 235–350 | 27–37 | 240 | 97.7% / 97% |
| IQ8PLUS-72-2-US | 235–440 | 27–45 | 295 | 97.7% / 97% |
| IQ8M-72-2-US | 260–460 | 30–45 | 325 | 97.8% / 97.5% |
| IQ8A-72-2-US | 295–500 | 32–45 | 349 | 97.7% / 97% |
| IQ8H-240-72-2-US | 320–540 | 36–45 | 380 | 97.6% / 97% |
Example: a 440 W panel on an IQ8PLUS
An example using only data-sheet numbers: a 440 W panel at the top of the IQ8PLUS pairing range 1.
| Step | Math | Result |
|---|---|---|
| Panel nameplate (DC) | Top of the listed pairing range | 440 W |
| Microinverter limit (AC) | Max continuous output | 295 VA |
| Per-panel DC-to-AC ratio | 440 ÷ 295 | about 1.49 |
| 20 such panels | 20 × 295 VA | 5,900 VA of AC for the system |
Enphase lists this pairing as common, so the ratio is a design choice, not an error. On the brightest, coolest hours the panel can offer more than 295 VA, and the extra is clipped. For most hours a rooftop panel makes well under its rating. See DC-to-AC ratio for why designers accept this.
Where you find microinverters
On the roof, they hide under the panels, so you rarely see them. Near the meter you will usually see a small combiner box or gateway. That box collects the AC branches and sends data to your app.
On a quote, look for the model number, such as IQ8PLUS, and a count that matches the panel count. Check that the system AC size equals units × continuous VA, not peak VA.
In the app, each panel shows as its own tile. That makes it easy to spot one panel that is dirty, shaded or failed. Our monitoring and fault-finding page explains what to look for.
Where microinverters win and lose
Advantages
Drawbacks
- CEC weighted efficiency of 97%–97.5% on IQ8 is below the 99% printed for some string inverters 5.
- Dozens of electronic units on the roof; replacing one means roof access.
- Mixing generations has limits: Enphase says IQ7 units cannot be added to a site with IQ8 units on the same gateway 1.
- The DOE notes microinverters can be more expensive 3.
Limits of microinverters
Each unit has a fixed AC limit. A big panel on a small unit will clip on the best hours. Match the panel to the unit’s listed pairing range.
Some models fit only some homes. The IQ8M and IQ8A sheet says they support split-phase 240 V installs only 2. Most US homes are split-phase, but some apartments and businesses are not.
Units sit on a hot roof. The IQ8M and IQ8A sheet lists an ambient range of −40 °C to 60 °C 2. Mixing old and new models on one gateway is also limited 1.
Cost drivers, lifespan and warranty
We do not print prices. The cost drivers are the number of panels, the model needed for your panel size, the gateway, and roof work.
Because you buy one unit per panel, cost grows with panel count. The DOE says microinverters can be more expensive than a single inverter 3. See the cost by system size guide.
Warranty terms are long. The IQ8M and IQ8A sheet prints a limited warranty of up to 25 years 2. The DOE’s rule of thumb is still to plan for inverter replacement during a 25-year array life 4. Ask whether labor to reach the roof is covered.
How a microinverter system is installed
A licensed installer and electrician do this work. Here is the order.
- The designer checks each panel’s wattage and current against the unit’s listed pairing. Enphase offers a compatibility calculator.
- They split the panels into AC branches within the 20 A branch limit 1.
- The installer gets a building and electrical permit and applies to the utility.
- Crews fix a microinverter to the racking under each panel, then mount the panels.
- An electrician runs the AC trunk to a combiner and a breaker in your panel.
- The gateway is set to the utility’s grid profile. Enphase ships units with IEEE 1547 default settings and changes them through the gateway 2.
- An inspector checks the work, then the utility gives permission to operate.
Maintenance: watch the panel tiles
Open your app once a month. Look for one tile that is much lower than its neighbours on a clear day. That points to shade, dirt or a failed unit.
Keep the gateway online. It sends data and updates. If your router changes, ask your installer how to reconnect it.
A failed unit means roof work. Do not go on the roof yourself. Our solar repair page explains what a visit covers.
Warning signs and when to call a pro
Call your installer or a licensed electrician if you see any of these.
- One panel tile shows zero while the others work.
- Many tiles show zero, which may mean a tripped breaker or a branch fault.
- The app shows “not reporting” for days.
- Burning smell, scorch marks or loose wires under the array.
- The combiner box breaker keeps tripping.
Safety rule
Microinverters carry 240 V AC on the roof. Never reset breakers over and over or unplug roof cables. Call a licensed electrician.
Standards and codes microinverters meet
Microinverters are grid-tied inverters, so the same rules apply. The IQ8M and IQ8A sheet lists CA Rule 21 (UL 1741-SA), UL 62109-1 and IEEE 1547:2018 (UL 1741-SB 3rd Ed.) 2. IEEE 1547-2018 was published on 6 April 2018 7.
For fire safety, the sheet says the units are UL Listed as PV rapid shutdown equipment. They meet NEC 2014, 2017, 2020 and 2023, section 690.12 2. Rapid shutdown lowers roof voltage so firefighters can work safely.
The California Energy Commission lists inverters that pass lab tests. Supplement SB listings need UL 1741 3rd Edition and IEEE 1547-2018 compliance 8. Your local inspector decides which NEC edition applies.
Microinverter vs other inverter types
| Microinverter | Power optimizer + string inverter | Plain string inverter | |
|---|---|---|---|
| Tracks each panel | Yes | Yes | No |
| Where DC becomes AC | Under each panel | One box on the wall | One box on the wall |
| Roof wiring | AC, 240 V | DC string | DC string |
| CEC efficiency examples | 97%–97.5% 1 | 98.6% optimizer, 99% inverter 6 5 | 99% (HD-Wave) 5 |
| If one unit fails | One panel stops | Inverter fault stops all | Inverter fault stops all |
| Learn more | — | Power optimizer | String inverter |
Misconceptions
- Myth Microinverters give backup power.
- Reality Not on their own. They follow the grid and shut down when it fails. Backup needs a battery and a system controller.
- Myth Microinverters always make more energy.
- Reality On a sunny single-face roof, a high-efficiency string inverter can match them. The gain comes mostly from shade and mixed faces.
- Myth Any panel works with any microinverter.
- Reality Each model lists a panel pairing range and voltage window. Outside it, output or warranty may suffer.
Microinverters in SC, GA and VA
Size caps are often set in AC. For microinverters, AC size is the unit count times each unit’s continuous rating. Dominion Energy South Carolina’s Solar Choice rider 11 and Duke Energy Carolinas’ Rider RSC 12 cap residential systems at 20 kW AC.
Georgia Power asks for inverter spec sheets showing UL1741SB and IEEE1547-2018 9, which IQ8 sheets print. Virginia requires systems to meet NEC, IEEE and testing-lab standards such as UL 10.
Should you choose microinverters? Checks before you sign
Microinverters make most sense with shade, several roof faces, or a wish for panel data. Before you sign:
- Match each panel’s wattage and current to the unit’s listed pairing range.
- Work out AC size from the continuous AC rating, not peak.
- Ask whether backup is in the design. Microinverters alone give no outage power.
- Ask who pays labor if a unit fails under warranty.
- Read the warranty document for the exact model.
Related reading
Questions about microinverter
Are microinverters better than a string inverter?
On shaded or multi-face roofs they usually recover more energy, because each panel works alone. On a clear, single-face roof, a string inverter with higher CEC efficiency can match them with fewer parts. The roof decides more than the technology. Ask your installer to model both.
Do microinverters work during a power outage?
Not on their own. They follow the grid and shut down when it fails, as IEEE 1547 requires. Some, such as Enphase IQ8, can run backup circuits with the maker’s system controller and a battery. Ask whether your quote includes that gear.
Can microinverters be added to an existing string system?
Not to the same string. A separate microinverter array on its own AC branch is possible. It needs a design review, a permit and a utility notice. A licensed installer should check that the main panel can take the extra breaker.
What does MLPE mean?
MLPE means module-level power electronics. It covers any device that works at each panel, such as microinverters and power optimizers. The term comes up in rapid-shutdown talks because MLPE can drop each panel to a safe voltage.
Why does a microinverter clip my panel’s output?
Because the panel’s DC rating is higher than the unit’s AC limit. A 440 W panel on a 295 VA IQ8PLUS is a listed pairing. The unit caps output on the strongest hours. Most of the day, the panel makes less than the cap, so little is lost.
How long do microinverters last?
Makers print warranties, not lifespans. The Enphase IQ8M and IQ8A sheet prints a limited warranty of up to 25 years. The DOE still advises planning for inverter replacement during a 25-year array life. Check what labor the warranty covers, since roof access adds cost.
How many microinverters do I need?
One per panel in most designs. Some products handle two or more panels, but the IQ8 family is one unit per panel. Your system AC size is the unit count times each unit’s continuous VA rating.
Are microinverters safer than string inverters?
They avoid long high-voltage DC runs on the roof, and IQ8 units are listed as rapid-shutdown equipment. String systems meet the same NEC rules with optimizers or other devices. Both are safe when listed gear is installed by licensed pros.
Can I mix microinverter models?
Within limits. Enphase says IQ7 units cannot be added to a site with IQ8 units on the same gateway. Mixing models in the same family can work. Ask your installer before adding or swapping units.
Sources
- Enphase Energy, IQ8 Series Microinverters data sheet (DSH-00378-5.0-EN-2026-07-13), retrieved .
- Enphase Energy, IQ8M and IQ8A Microinverters data sheet (DSH-00243-3.0-EN-2024-12-10, distributor-hosted copy), retrieved .
- US Department of Energy, Solar Integration: Inverters and Grid Services Basics, retrieved .
- US Department of Energy, Solar Photovoltaic System Design Basics, retrieved .
- SolarEdge, Single Phase Inverter with HD-Wave Technology for North America data sheet (12/2020/V01, distributor-hosted copy), retrieved .
- SolarEdge, Power Optimizer S440 / S500 / S500B data sheet (DS-000091-ENG, 8 Nov 2022, government-hosted copy), retrieved .
- IEEE Standards Association, IEEE 1547-2018, retrieved .
- California Energy Commission, Inverter Listing Request Instructions (rev. 26 Aug 2025), retrieved .
- Georgia Power, Behind-the-Meter Interconnection Summary for Residential Customers (rev. 15 Aug 2025), retrieved .
- Code of Virginia §56-594 (net energy metering), retrieved .
- Dominion Energy South Carolina, Residential Solar Choice rider (Rider to Rate 5), retrieved .
- Duke Energy Carolinas (SC), Rider RSC Residential Solar Choice, retrieved .
Expert review
Written by the HyreSolar Research team. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.
How the numbers were checked: Every specification copied from Enphase data sheets DSH-00378-5.0 (July 2026) and DSH-00243-3.0 (Dec 2024); comparison figures from the SolarEdge HD-Wave and S440 sheets; mechanism from the DOE primers; state facts from sc-local/facts.js, the Georgia Power summary and Va. Code §56-594. The worked example divides and multiplies printed numbers only.
Suggest a correction. We fix errors and say what changed.