GeoAlaska committed to start geothermal drilling on Augustine Island
The first geothermal exploration well in Augustine Island, Alaska is now being planned as part of a potential 200-MWe development by GeoAlaska.
GeoAlaska Inc., in partnership with Ignis H2 Energy, has announced plans for geothermal drilling at Mt. Augustine, an active stratovolcano located on Augustine Island in the Cook Inlet in Alaska. Drilling of the first well, Kamishak_001, is currently planned.
GeoAlaska has classified Mt. Augustine as a “blind” geothermal system. This means that it lacks surface manifestations but is structurally comparable to Cerro Pabellón (Chile) and the Kakkonda (Japan) fields. Updated modeling now estimates the site’s capacity at 204 MWe (P50), with a potential range between 167 and 243 MWe. Development costs are projected at approximately $2.5 million per installed MWe.
Recent geophysical surveys, including magnetotelluric (MT), gravity, and seismic surveys, have confirmed the presence of both shallow and deeper geothermal systems beneath the volcano’s southern flank. These prospects lie under a clay-rich sedimentary cap, interpreted to trap hydrothermal fluids within fractured basement rocks. A deeper low-resistivity anomaly, believed to represent a magmatic chamber, is modeled at temperatures exceeding 840°C.
The well is planned as a NE/SW deviated well to intersect both the shallow (200–350°C) and deeper (350–400°C) targets. According to Guy Oliver of Ignis Energy, “By targeting both zones in one wellbore, we minimize costs while maximizing information on thermal gradient, fracture presence, and fluid connectivity.”
Despite the project’s remote location roughly 100 km southwest of Homer, Oliver notes that logistical risks are manageable. “Augustine Island offers good access via shallow sandy beaches and sheltered landing sites. Once equipment is in place, we can drill year-round,” he said. The well site sits below the snow line and is advantageous from a risk potential of storm surge and/or tsunami events.
Beyond its technical promise, Mt. Augustine could become a strategic asset for Alaska’s Railbelt grid, which supplies over 75% of the state’s population and currently depends on Cook Inlet natural gas. With supply expected to fall short by 2027, geothermal offers a unique opportunity to provide round-the-clock, carbon-free baseload power.
“Geothermal is the only renewable capable in the Region of delivering 24/7 baseload low carbon power,” said Oliver. “A project of this scale would be a key part of Alaska’s future energy mix. The highest and best use of the limited gas supply in the Cook Inlet region is to heat Alaska’s homes and commercial buildings.”
The project was recently featured in the Talk of Alaska podcast by Alaska Public Media, featuring Gwen Holdmann (ACEP), John Eichelberger (Alaska DNR), and Anthony Pennino (GeoAlaska). Listen here.
Source: Email correspondence
