Will I have power during a utility outage?

Discussion in 'Frequently Asked Questions' started by scott, Mar 20, 2015.

  1. scott

    scott Administrator Staff Member

    This depends on your system type. The majority of solar PV systems installed today are strictly grid-interactive systems. These type of systems do not have batteries. The energy generated by solar during the day is either used by the home, or the excess is sold to the grid. In the united states (and other areas), these grid-interactive inverters are required to stop producing electricity when the grid is down. It is referred to as anti-islanding (UL 1741). This means that when the grid is down, your solar will also shutdown. The intent is to protect linemen repairing the system and allow the utility to full denergize sections of wiring.

    If your system has batteries, the system also likely has a transfer switch. When the grid is down, the system (either automatically or manually) disconnects form the grid and uses power from solar and the batteries to power a panelboard in your home.

    Grid-interactive without batteries and grid-interactive with batteries (bimodal) are the most common scenarios, but there are other options available for grid connected systems. For example, the new SMA Sunnyboy inverters come with a feature known as the Secure Power Supply (SPS). This allows a single outlet to be wired to the inverter. When the grid is down, you can manually flip a switch that disconnects the inverter from the grid and powers the outlet. There are no batteries in this system so the outlet when only be powered while the sun us out. Here is a explanation of SPS:

  2. JesusMop

    JesusMop Member


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