Chief Volcano watcher discusses geothermal issues

How far can the Big Island safely push geothermal development to meet growing energy demands throughout the island and state of Hawai`i? Scientists at the Hawaiian Volcano Observatory wrestled with that question during a recent Park after Dark event. In response to audience questions, Chief Scientist Jim Kauahikaua said available historical data casts doubt that drilling into a magma chamber would trigger a problematic eruption. 

“There are a few examples of geothermal drills going into magma bodies and none of them have started any lengthy eruptions,” Kauahikaua said. “One in Iceland in 1997 erupted for about 15 minutes, but none of them had any impact on the production.” Kauhakaua also addressed the issue whether an earthquake could disrupt a geothermal well or cause uncontrolled emissions. 

“Unfortunately, HGPA was started just after the magnitude 7.7 earthquake, so we don’t have that as an experience point,” Kauahikaua said. “But HGPA continued to produce through the two next largest ones, which were a 6.2 and a 6.7. PGV production started in 1992, and it weathered the 2006 earthquake, which was on the west side.” 

However, he cautioned that no one can definitively say that either scenario couldn’t occur. The questions were prompted in part by a June, 2012 Volcano Watch article from HVO scientists warning about over-development of the volcanic resource along Kilauea’s volatile east rift zone. The article said an eruption’s effect on the industry could be severe, if sites were covered by lava and cut-off the energy supply for an extended period of time. 

Puna Geothermal Venture presently pumps out 38 megawatts of energy on volcanic lands outside Pahoa, but accounts for only a fraction of the island’s overall power grid. Scientists said if a 500-MW power generation facility were developed and exported power to O`ahu and Maui, then a volcanic disruption would have a state-wide effects.

By Ken Hupp - 67AM KPUA News
Posted: Monday, October 1st, 2012 9:18 AM HST
source: http://www.kpua.net