The solar industry on Oahu continued to shrink last month.
In October, the city Department of Planning and Permitting issued 307 permits for solar electric systems, down from 367 in the same month last year, a drop of 16 percent, according to data compiled by Marco Mangelsdorf, who tracks rooftop solar permits and is president of Hilo-based ProVision Solar.
Over the first 10 months of this year, the number of solar permits issued is down 45 percent compared with the same period in 2016, Mangelsdorf said.
So far this year the value of all solar systems permitted on Oahu is down 58 percent at $86.92 million. At this time last year, total sales were $206.28 million.
The number of issued permits has been dropping since the state ended a popular solar energy incentive program called net energy metering (NEM) in 2015.
NEM participants are credited the full retail rate for the excess energy their solar system sends into the electric grid. For many homeowners, that means they cut their electrical bill to $18 a month.
With the option of NEM systems off the table, some homeowners are opting for solar systems connected to batteries. The solar panels charge the batteries during sunny hours for use at night or when clouds block the sun.
Sales of battery systems have not been robust enough to make up for the drop in sales following the end of the NEM program.
“The addition of battery storage has yet to make much of a dent,” Mangelsdorf said in an email.
Roughly 25 percent of PV permits issued last month included batteries, about the same monthly percentage over the previous six months, he said.
“With close to 48,000 net energy metered … accounts on Oahu, there could be a lucrative market for adding battery storage to existing NEM customers for the simple reason that if the grid goes down, their battery-less NEM investments shut down as well,” Mangelsdorf said.
“That said, this potential market is rather nascent at this point with all of two battery-only permits issued in October and 20 total since we’ve began tracking this data point in May.”
