The number of photovoltaic permits issued in Hawaii County declined 18.8 percent in October but is still up for the year.

There were building permits issued for 78 solar electric systems last month compared with 96 in October 2017, according to Marco Mangelsdorf, who tracks rooftop solar permits and is president of Hilo-based ProVision Solar.

Over the first 10 months of this year, 870 PV permits were issued compared with 728 in 2017, a year over year increase of 19.5 percent.

The top three permit pullers in 2018 on the island are Sunrun, ProVision Solar and Renewable Energy Services.

Mangelsdorf said Hawaiian Electric Cos.’ introduction last month of the Public Utilities Commission-mandated Net Energy Metering Plus program will allow its 70,000-plus NEM customers to add additional solar generation to their existing systems as long as there’s zero export of that new generating capacity.

“NEM Plus had been a long time in gestation and is a most welcome arrival for the PV industry to be able to offer those homeowners interested in expanding their systems,” Mangelsdorf said. “A key part in bringing more roof top solar online in the state rests on increasing the daytime demand for power due to circuit and system limitations coming from adding more and more distributed generation solar to island grids. Putting more electric vehicles on the road and charging them during daylight hours would accomplish a number of important things: promote more roof top solar, encourage existing NEM customers to go NEM Plus and consider getting an EV (electric vehicle) and accelerate the transition in ground transportation away from petroleum products.”