Last May, Hawaii’s Kīlauea volcano erupted suddenly, starting a weeks-long lava creep that destroyed dozens of homes and required thousands of residents to be evacuated. Among the structural casualties, the lava also threatened an important source of electricity on the Island of Hawaii: the Puna Geothermal Complex.
Now, the company behind Puna is projecting that the complex may be restarted by the end of this year, following a potential renegotiation of its contract with Hawaii Electric Light Company.
Geothermal plants like Puna create electricity by using the natural heat of underground rocks to heat a working fluid that produces steam to drive a turbine. Puna provided 25 percent of the electricity that served Hawaii (just the Big Island, not the whole Aloha State). So it was an important low-carbon energy source on an island that has historically imported oil to meet its primary energy needs. Although the Big Island has been aggressively incorporating solar power and energy storage onto its grid, petroleum still plays a prominent role in serving the island, which not only creates carbon emissions but also drives the price of electricity up for residents because the oil must be imported.