Hawaiian Electric Co. has approved 420 residential rooftop solar systems attached to batteries on Oahu, but the city Department of Planning and Permitting has given building permits to only 33.
City officials say they want to be certain the new technology is safe before approving units.
The solar industry wants the city approval process streamlined and says it is working with DPP to do just that.
Solar systems attached to batteries store power during daylight to use at night or in cloudy conditions. In October 2015 the state limited the number of new solar systems that can send excess power to the electric grid for credit. That made battery-connected solar systems more popular. These systems, known as “self-supply,” do not send excess power to the grid, but can take power from the grid when needed.
The change to battery-connected solar systems was prompted by concerns about the stability of the grid if too much solar power was feeding into it.
“The technology involved is ever-changing, and we — government and the industry — have been challenged to keep up with the technology,” said Timothy Hiu, DPP deputy director. “Our thorough review of plans with a battery component would sometimes lead to delays in approval, but this was only because our concern is the health and safety of the homeowner, public and PV (photovoltaic) installers.”
Will Giese, spokesman for Inter-Island Solar Supply, said multiple customers reported having to submit more than five rounds of plans, reviews and comments.
“This process, until recently, was taking nearly six months per installation, a simply unsustainable time frame for contractors who rely on a steady stream of operating capital,” Giese said.
The permitting process should speed up after local solar industry representatives met with DPP last week about the permitting for Tesla Powerwalls, one of the home battery systems currently for sale, said Colin Yost, principal at Honolulu-based solar company
RevoluSun.
“Once it’s understood how residential batteries work, it becomes clear that they’re just like a refrigerator or any other UL-tested appliance in your home,” Yost said.
The solar industry has been able to work closely with the DPP to understand and address the department’s concerns with permitting solar systems that have batteries attached, Giese said.
Hiu said he expects the DPP’s review process will speed up after launching an online permitting system this month.
“With the ability for contractors to self-issue permits online, we expect the processing time to be reduced significantly,” Hiu said. “We continue to work with the industry to enable us to process these building permits in a more timely manner.”
Hiu said the department’s approval process for self-supply systems was delayed as reviewers worked to understand the battery technology.
RevoluSun is seeing sales of self-supply systems grow as “regulatory barriers disappear and significant numbers of batteries arrive in warehouses on Oahu,” Yost said.
The battery, or self-supply, solar system was one of two programs that replaced the popular “net energy metering” solar program, which paid residents the full retail rate for excess electricity sent into the grid. That program ended in October 2015. The other program, grid supply, which is a watered-down version of net energy metering, was recently opened back up again to customers after meeting its cap last year.
In a March order the PUC clarified that the solar industry could bring on more customers for the maxed-out grid supply program to use the space of unfulfilled net energy metering applicants who dropped out before installing their systems.
Now there is space for 15.85 megawatts, or roughly 2,000 solar energy systems, in the grid supply program. As of Tuesday there were 150 grid supply applications awaiting approval from HECO.
