- Hawaiian Electric Co. has opened up additional capacity in its popular Customer Grid Supply (CGS) program, which allows residential rooftop solar systems to export excess energy back to the grid.
- After eliminating retail net metering in 2015, Hawaiian regulators allowed HECO to offer the CGS program and a Customer Self Supply (CSS), which was less popular and does not allow for exports to the grid. The CGS program previously hit its caps in Oahu, Maui County, and Hawaii Island.
- But now, the utility says it has found space for at least 20 MW of CGS capacity by transferring capacity previously allocated to private solar systems that were never completed. That amounts to about 2,800 typical Hawaii private rooftop solar systems, according to Pacific Business News.
HECO's announcement of new grid-supply capacity is big news for the solar industry in Hawaii.
While there have been indications the less-popular self supply program was beginning to gain traction, the additional and more-lucrative grid supply capacity is likely to be filled quickly.
Under the customer grid supply program, customers can export electricity to the grid and are paid are paid a fixed rate between $0.15/kWh and $0.28/kWh, depending on the island.
The self-supply program, by contrast, discourages exports to the grid and incentivizes customers to consume their own solar power through the installation of battery storage.
The idea is to reduce the stress on the distribution system from customer-sited solar exports and mitigate for HECO's solar oversupply problem at mid-day.
According to HECO, there are hundreds of CGS applications already in line for processing and they will be examined through Oct. 21, 2017. The utility offers online Locational Value Maps for customers to check circuit capacity in their neighborhood.
HECO said it is looking to advanced inverters that might allow circuits to handle more residential solar, and encouraged grid-supply applicants to install a properly-sized system.
"Oversized systems cost more and can potentially export more electricity than the homeowner will receive credit for on their electric bill," the utility said. "Installing a 'right-sized' system helps leave room for future interconnections on the circuit, making space for others."