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.
In the Rockaways, where nearly 14,000 customers
still had no power as of Monday morning, volunteers set up a makeshift solar
charging station between a car roof and a shopping cart. A multipanel,
battery-tied system is helping fuel a relief center’s operations.
In the storm’s wake, solar companies have been
donating equipment across New York and other stricken areas to function as
emergency power systems now and backups in the longer term. It is important,
executives say, to create smaller, more decentralized ways of generating and
storing electricity to help ease strain on the grid in times of high demand or
failure.
“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, a leading installer that has donated generators after Hurricanes
Katrina and Sandy and is developing a battery backup system for its customers.
“But the components are starting to come together.”
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.
“You size the battery system to go with that, and
then the system will work just on those dedicated circuits,” said Tony
Clifford, chief executive of Standard Solar, an installer based in Maryland.
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.
Although demand for battery backup is not yet
widespread, interest tends to go up after storms, said David Panico, senior
vice president of the industrial power group at SunWize, a solar supplier that
provided a low-cost mobile system to the Rockaway Beach Surf Club, a hub of
that area’s relief effort.
But a drawback is that residents have to figure out
where to put the batteries — a particular quandary for those with homes
vulnerable to flooding.
Some are looking at electric vehicles as
potential backup energy sources instead. In some cases, a car could fuel a
house for days on a single charge.
“With
something like a Chevy Volt, you might be able to power from eight to 16 hours
at a time,” said William Acker, executive director at New York Battery and
Energy Storage Technology Consortium, an industry group. A Tesla, which has
greater battery capacity, could theoretically run for days, even without being
recharged by the solar panels. “The advantage there is that that battery is
doing something else most of the time.”
That sort of setup, though, is not quite practical
yet. Although the technology already exists, the required inverters are 50 to
100 percent more expensive than the standard ones, and electrical codes do not
yet accommodate them, said James Worden, the chief executive of Solectria
Renewables, an inverter manufacturer. In addition, because solar panels do not
always produce a strong, steady stream of electricity, the average home solar
array does not have sufficient strength to consistently charge a car.
“Right now, it’d be better to have a very small
Honda generator” that runs on gasoline as a backup, Mr. Worden said. “But if
we’re going to have more and more storms that are more severe and power outages
are just going to become more frequent, then there might have to be a
technology shift and people will change what they’re doing.”
Some of that change, driven by environmental
advocates, energy companies and residents, is already happening. The makeshift
charging station on Beach 91st Street in Rockaway Beach, which has been
replaced by a much larger one, for instance, came courtesy of R. David Gibbs, a
renewable energy engineer at Solar One, a nonprofit educational group, and
Walter Meyer and Jennifer Bolstad of Local Office, a husband-and-wife landscape
architecture firm. They have been raising money and bringing more mobile solar
generators to the Rockaways as part of a larger effort to meet its energy
needs.
Even in the middle of a disaster, a small charging
station can help, residents said, giving them the ability to charge cellphones
or electronic game devices to entertain their children.
“Being on the outskirts puts us at a loss,” said Tim
Hill, a property manager who has been an organizing force on Beach 91st Street.
Just having the station in the storm’s aftermath
opened Mr. Hill’s eyes to the possibilities for an even larger, more permanent
generator.
“Being able to have enough electricity to jump-start
a car, run an electric heater for the night or have a Wi-Fi hot spot,” he
added, “would allow people to maintain that sense of normalcy that is so
necessary, from an emotional and psychological perspective to a physical,
survival perspective.”
Source:
NYtimes. By Diane Cardwell
