The Alaska Center for Energy and Power has completed a conceptual model of geothermal power at the Pilgrim Hot Springs in north western Alaska.
The Pilgrim geothermal system (PGS) is located125 miles south of the Arctic Circle 45 miles north of the city of Nome. Extensive drilling and research work took place 30 years ago from 1979-1982. In 2011 work at Pilgrim resumed with a remote sensing effort to try to better understand the spatial extent of the thermal anomaly. In addition, existing (old) wells were relogged.
Drilling efforts exploration efforts have been the relatively high geochemically - predicted subsurface temperatures of up to 293°F (145°C), along with the relatively good accessibility.
The conceptual model study this year concluded “Our recommendation is to proceed with Option 2 (drill into the upflow zone to test how much fluid the most potent and permeable part of the known geothermal system is capable of producing), should funding be identified to support an additional drilling program. The high cost of energy in the region appears to make even a modest project such as a 2MW e binary plant economic to develop. This is substantiated by a recent (May, 2013) agreement between the land owner, Unaatuq LLC, and Potelco, Inc (a subsidiary of Quanta Services), to develop the resource and export power to Nome should the resource be shown capable of sustaining a minimum production level of 2MW e.”
The geothermal water at Chena Hot Springs was about 165 degrees when the power plant was developed. It is now about 178 degrees following a deepening of two wells there. At Pilgrim hot springs, the water is warmer, about 190 degrees, and the higher temperature should make the technology concepts developed for Chena Hot Springs work even better there.
The Pilgrim geothermal system has potential to export power to Nome (a very high cost area). Work will likely continue by ACEP. Aside from whether the warm water flow can be sustained, a major question is whether the project will support the cost of a 50-mile, long-distance transmission line to Nome at a rough cost of half a million dollars per mile.