Some companies are selling lithium ion battery systems to store
electricity generated by residential solar systems. Above, workers
install solar panels at a home in Pompton Lakes in 2010.
Star-Ledger file photo
The benefit of such systems is that in power outages, there remains a day or two storage supply of electricity to power a home's lights and appliances.
But the storage systems are expensive, and it remains unclear what the payback is or even whether there is one, Fortune reported.
New Jersey has been a leader in solar energy, with more than 20,000 solar projects installed statewide. But the installations have come with the help of subsidy credits, and have yet to prove a consistent return on investment.
The U.S. currently has no subsidies for solar storage.