Technology
A grid-tied system is a solar photovoltaic or other renewable energy installation that is connected to the public electricity grid. In a grid-tied solar system, the solar panels supply power to the home or facility, and any excess generation can be sent into the grid (often earning credits via net metering), while any shortfall in power (like at night) is drawn from the grid. Grid-tied systems typically do not use batteries for storage; instead, they rely on the grid for backup. These systems require anti-islanding safety features (so they shut off during outages to protect line workers) and allow for efficient use of solar power in conjunction with utility electricity.