THE HONEST ANSWER

CAN YOU BUILD YOUR OWN BALCONY SOLAR SYSTEM?

Technically, sometimes. Legally and safely, it's more complicated than buying a panel and a microinverter separately. Here's why.

1Standard tests the WHOLE system, not parts2Manufacturers certified so far0States where DIY-assembled systems are confirmed compliant
THE STANDARD, EXPLAINED

UL 3700 TESTS THE WHOLE SYSTEM - NOT THE PARTS.

UL 3700 is the safety standard that launched in January 2026 specifically for plug-in solar systems. It tests the COMBINATION of panel, microinverter, and cabling working together as one unit - not each piece in isolation.

AUTOMATIC SHUTOFF
The system must shut off automatically when disconnected from the grid.
ANTI-ISLANDING PROTECTION
The system must detect a power outage and stop sending power into the grid, protecting utility workers.
OVERLOAD PREVENTION
The system must not exceed safe output for your home's wiring and outlet.
WEATHERPROOFING
The system must withstand outdoor conditions over its rated lifespan.
The key pointEach of these depends on how the panel and microinverter work TOGETHER - their combined electrical behavior, not just each part's individual spec sheet.
THE ACTUAL ISSUE

A "UL-LISTED" PANEL PLUS A "UL-LISTED" MICROINVERTER ISN'T THE SAME AS A UL 3700-CERTIFIED SYSTEM.

This is the part that trips people up. Plenty of individual solar panels and microinverters on the market carry SOME UL certification - but that typically covers the component on its own, for general electrical safety - not the SPECIFIC combination's behavior as a complete plug-in system.

If you buy a panel from one manufacturer and a microinverter from another, and connect them yourself, that exact combination has almost certainly never been tested together. There's no guarantee the anti-islanding protection, the shutoff timing, or the overload behavior works the way it would in a tested kit.

A CERTIFIED KIT
Tested as one unit.
Panel + microinverter + cabling tested together, as sold, by an independent lab. The combination you receive is the combination that was tested.
A SELF-ASSEMBLED SYSTEM
Tested as separate parts.
Individual parts may each be listed for general electrical safety. The SPECIFIC combination you've built has not been tested together. No lab has verified how they behave as a system.
YOU CAN STILL CUSTOMIZE - JUST DIFFERENTLY

COMBINE CERTIFIED KITS INSTEAD OF MIXING COMPONENTS.

If you want more control over your system's total size, brand mix, or budget than a single kit offers, you can combine MULTIPLE complete, certified kits - rather than mixing individual parts.

Each kit is independently certified on its own. Running two separate 395W certified kits side by side gets you 790W of certified capacity, within a single state's wattage limit, without ever creating an untested combination.

Related: NEC vs. state law on plug-in solar →

FIND THE RIGHT POWER
FOR YOUR HOME.

FIND MY POWER →
HONEST - NOT JUST A SALES PITCHSOURCED FROM ACTUAL UL 3700 SCOPEUPDATED AS CERTIFICATION EXPANDS