The state Public Utilities Commission is giving the solar industry more time to add customers who are looking to get credit on their electrical bills for the excess energy their rooftop systems produce.

A solar industry representative said up to 4,300 additional electricity customers statewide will be eligible to get credit for the excess energy their systems export into the grid, after the PUC filed an order earlier this month.

Robert Harris, director of public policy for solar company Sunrun Inc., said the ruling should clear up a backlog of solar systems currently waiting, “as well as immediately create room for new sales.”

In the order, the PUC clarified that the solar industry could bring on more customers for the maxed-out “grid-supply” program, which credits customers for the energy their solar systems export into the grid, to use the space of unfulfilled net energy metering (NEM) applicants who dropped out between October 2015 and Oct. 21 of this year.

“This is exactly the type of transition we were asking for,” said Colin Yost, principal at RevoluSun. “It helps consumers. It helps the industry.”

The new grid-supply applicants had not been allowed to replace those who dropped out of NEM because Hawaiian Electric Co. had interpreted the PUC’s initial ruling on Dec. 9, which merged the programs, to be the start date of the forfeited NEM applications eligible to be substituted with a grid-supply system.

The solar companies and HECO had been at an impasse until the date was clarified. Under the timeline beginning Dec. 9, which HECO said was correct, only 10 megawatts, or 1,400 customers, would have been eligible for the program, according to Sunrun’s Harris.

After the grid-supply program hit its limit in 2016, solar systems were prohibited from sending excess energy into the grid. This resulted in new solar customers being unable to earn credit for their systems and, in most cases, buying a battery to hold the excess energy their systems produce.

About 700 customers on Oahu are waiting for the grid-supply program, Yost said.

“There is over 5 megawatts of people waiting in the (grid-supply) queue right now on Oahu,” he said. “That’s approximately 700 people.”

On Dec. 9 the PUC opened up a possibility for hopeful grid-supply customers by allowing them to take the place of customers who never moved forward with their approved application for the NEM program. The loophole came after the PUC, which canceled the NEM program in October 2015, declined the industry’s request to increase the number of grid-supply systems that could be added.

While customers are still allowed to get credit for excess energy under the grid-supply program, the option is less lucrative than NEM. The NEM program credits customers the full retail rate when they return excess energy to the grid. The grid-supply program credits customers roughly 15 cents a kilowatt-hour.

The PUC said the “plain language” of the order clearly states that the capacity used by customers grandfathered into NEM before the end of the program in October 2015 who withdrew or canceled their applications may be transferred to the grid-supply program.

“Accordingly the commission concludes that the solar parties’ interpretation of the (order) is correct and that order applies to the capacity of all NEM applications that have been withdrawn or canceled since the closure of the NEM program in October,” the PUC order said.