Solar panels went idle during Sandy power outages just like regular power-NY Times

.
11/19/21, "Solar Companies Seek Ways to Build an Oasis of Electricity," NY Times, D. Cardwell

"When Hurricane Sandy wiped out the power in areas like coastal Long Island and the Jersey Shore, what should have been beacons of hope — hundreds of solar panels glinting from residential rooftops — became symbols of frustration. 

Despite the popular perception that installing solar panels takes a home “off the grid,” most of those systems are actually part of it, sending excess power to the utility grid during the day and pulling electricity back to run the house at night. So when the storm took down power lines and substations across the Northeast, safety systems cut the power in solar homes just like everywhere else.

“Here’s a $70,000 system sitting idle,” said Ed Antonio, who lives in the Rockaways in Queens and has watched his 42 panels as well as those on several other houses in the area go unused since the power went out Oct. 29. “That’s a lot of power sitting. Just sitting.”

Yet there are ways to tap solar energy when the grid goes down, whether by adding batteries to a home system or using the kinds of independent solar generators that have been cropping up in areas hard-hit by the storm....

“The grid won’t evolve into something more distributed and fault-tolerant overnight — it’s still dependent upon a centralized system,” said Ben Tarbell, vice president for products at SolarCity....

Generally, home systems like Mr. Antonio’s are engineered to feed electricity from the roof array through an inverter and into the home’s electrical panel, sending the excess to the broader electric grid. But during a failure, the inverter automatically shuts down the system to guarantee that no electricity is flowing into equipment that workers will be trying to fix. The shutdown also ensures that the system’s current will sync with the grid when power is restored and guards against damaging the lines.

Certain systems allow solar panels to run a household directly during prolonged power failures, generally combined with battery storage to keep the power functioning around the clock. Those require installing a separate electrical panel and a more complicated inverter that would switch the flow of electricity entirely over to the house, perhaps to a few critical circuits to run, say, the refrigerator, some lights, television and minimal heat....

The cost of adding battery storage to an existing system can range from $500 to $30,000, depending on how large the solar array is and how much the customer wants to be able to run.  ...

“Right now, it’d be better to have a very small Honda generator” that runs on gasoline as a backup, Mr. Worden said."...via Free Republic

.