Grid-tied
By Priya Nair · Last reviewed Describes a solar system whose inverter synchronizes with the utility grid and feeds power into the home's existing circuits, letting appliances draw solar first and grid power for the balance. Plug-in solar is grid-tied by definition — which also means it must shut down when the grid fails.
Why it matters
Grid-tied is the property that separates plug-in solar from solar generators and off-grid kits: it is what makes the bill go down automatically, what triggers interconnection rules, and what rules the product out as blackout backup. Most buyer confusion in this category traces to missing this one distinction.