Point of Interconnection (POI)

The point of interconnection (POI) is the electrical location where a solar or storage plant connects to the utility system and where its grid code compliance is measured.

The utility or grid operator writes its limits for the POI: maximum export, maximum import, power factor, ramp rate, and voltage. A power plant controller measures active power, reactive power, voltage, and frequency there and dispatches the inverters behind it so the plant as a whole meets those limits, net of losses and auxiliary load. IEEE 1547 calls the equivalent location on a distribution system the point of common coupling.

Also called: Point of common coupling, PCC, Interconnection point