Question: Can People Use Rooftop Solar Power During An Emergency? Answer: It Depends

A controversy is brewing in Florida following the devastation caused by Hurricane Irma. Many people in the state thought their rooftop solar systems would keep the lights on and the air conditioning running even after Irma knocked out power to millions of customers in the state. But it didn’t quite turn out that way.

In fact, many were shocked — SHOCKED! — to find out they are prohibited from operating their solar systems when grid power is not available by both state law and various policies put in place by local utility companies. Many were outraged to discover this, having assumed their solar panels would continue to supply power when their less fortunate neighbors had none.

The situation has led to a spate of news stories casting aspersions on greedy utility companies and feckless politicians. National news outlets like MSN felt constrained to report on the inability of home owners to rely on their solar systems after the storm passed through. But the real answer is somewhat more nuanced than that. As Florida Power and Light points out, it can’t very well send its crews out to fix downed wires if electricity is still coursing through the system. In general, utility workers do not take kindly to being electrocuted, regardless of their high wages.

Verify, a service of TV10 News in the Tampa Bay area, reached out to several utility companies to find out what’s what when it comes to solar power in an emergency.  TECO, the utility company in the Tampa area, sent this response. “Any issues or ‘restrictions’ would be related to technology, not regulatory. If a customer’s solar system is connected to the power grid, it requires power from the grid to be operable. Inverters shut down when the power grid goes down. If the array has batteries, it can operate while the grid is down when isolated.”

Duke Energy contributed this statement: “The National Electric Code and IEEE Standards require Distributed Generators to disconnect from the grid during outages, not Duke Energy. Private solar without battery storage relies on the power grid 24/7 to operate properly. When the grid is not available they must disconnect for safety and power quality reasons. Private solar generators, just like our customers with emergency diesel generators, can design their systems to meet national codes and self-serve their energy needs during grid outages.”

The definitive answer appears to be that only solar systems that incorporate in-home storage batteries and a properly connected inverter can supply power in the event of a grid outage. Somehow, this state of affairs seems to have been lost for many solar customers who simply don’t understand how electricity works. They assumed their solar panels would still be available, but we all know about the word “assume” by now, don’t we?

None of which is to say that Florida’s utility companies aren’t bitterly opposed to rooftop solar systems, having just ponied up millions of dollars prior to the last election to back an amendment to the state’s constitution that would have virtually outlawed them permanently. What it does mean is that if you want your rooftop solar system to be there for you in an emergency, you need to make sure it has a storage battery — or two — included in the system.