What is solar islanding?

Solar islanding is when a home solar power system continues to generate electricity even though the grid is down. Many people would consider this a good thing, as your home still has power from your solar panels while everyone else has no power.

What happens if solar islanding isn't prevented?

Here's what could happen if solar islanding wasn’t prevented: The local grid goes down. Your grid-tied home solar power system still produces electricity. Once the panels have supplied electricity to your home, any excess energy flows back into the grid. Meanwhile, utility workers are repairing damaged power lines on the "should-be-dead" grid.

Do solar panels have anti-Islanding inverters?

The short answer is no. UL Standard 1741 requires every grid-tied PV system to have a built-in anti-islanding solar inverter, and the solar industry follows that standard. While these laws were initially meant to protect utility workers, they've since been amended to include protection for your solar panel system and electricity grid at large.

How does an islanding solar inverter work?

Your islanding solar inverter works independently from the power grid. If there's a storm or other event that knocks out the main power grid, your solar power system will continue running and providing power to your home. We mention this because many people mistake going solar with going off-grid, but that's typically not the case.

Should you install a solar panel system?

One of the main reasons people invest in solar power is to gain energy independence from the utility grid. However, adding a solar panel system doesn't necessarily mean that your home is immune to power outages or blackouts. During such an event, your grid-tied system might be turned off automatically to protect the grid from “solar islanding”.

Why do solar panels need anti-islanding protection?

The grid infrastructure is set up in such a way that it will shut down when it detects a severe problem. Without solar anti-islanding protection, your solar panels will continue to send voltage back to the grid, which could damage the grid hardware and lead to other costly losses.