The completion of large grid-scale projects and thousands of residential solar systems boosted the largest-ever annual increase in solar capacity on Hawaiian Electric’s five island systems, the company announced Friday.
Total solar capacity surged 21 percent, increasing from 745 cumulative installed megawatts in 2018 to 902 megawatts at the end of 2019. It was the largest one-year increase since the company began tracking solar capacity in 2005.
There are now an estimated 3.5 million solar panels producing electricity on the company’s five grids.
Three solar arrays built by Clearway Energy Group totaling 110 megawatts and Hawaiian Electric’s West Loch solar array producing 20 megawatts came online on Oʿahu in 2019.
In addition, nearly 3,500 new systems across Oʻahu, Hawaiʻi Island and Maui County were completed. Company officials say the rise supports Hawaiian Electric’s goal to reach the state’s next milestone of 30 percent renewable energy by the end of this year.
Installation of residential rooftop solar systems used by Hawaiian Electric customers increased 4.6 percent in 2019 from 2018, and Hawai‘i continues to lead the nation in rooftop solar adoption.
Year-end figures show that 19 percent of residential customers in Hawaiian Electric’s five-island service territory are using rooftop solar, up from 18 percent in 2018.
Hawai‘i’s percentage of residential customers with rooftop solar is more than double that of California, which is second at 6.6 percent; Arizona is third at 5.5 percent; Rhode Island and Guam, both fourth at 4 percent; and Utah at 3.6 percent, according to an analysis of 2018 data by the Smart Electric Power Alliance.
Residential rooftop solar systems installed on Oʿahu, Hawaiʻi Island, Maui, Molokaʻi and Lānaʻi rose to 77,801 in 2019 from 74,331 in 2018, up 4.6 percent.
Including commercial and grid-scale units, there are now 81,783 solar systems online, capable of producing 902 megawatts.
“The numbers show the adoption of residential rooftop solar remains strong, increasing year after year across all of our islands,” Hawaiian Electric senior vice president of customer service Shelee Kimura said in a press release.
“Rooftop solar is a critical piece of the renewable mix, and our plans call for tripling the amount already installed to help move the state toward a clean energy future.”
On Oʿahu, 37 percent of single-family homes now have rooftop solar; on Hawaiʻi Island, 21 percent; in Maui County, 27 percent.