How to generate power from a volcano

Posted by Paul Willis, EarthTechling

A plan to tap the geothermal potential of one of the Cascade Range’s most impressive volcanoes has been thrown open for public consultation.

The U.S. Forest Service (USFS) has begun the consultation to decide whether forest land near Mount Baker should be leased out to power companies for the purpose of producing geothermal energy.

How to generate power from a volcanoThe service is considering allowing the Bureau of Land Management (BLM) to open for leasing about 5,500 acres on the southeast side of Mount Baker.

The project is located in Whatcom County, Wash., in the Baker River watershed. The nominated lands are situated south of the Mount Baker Wilderness and east of the Mount Baker Nature Reserve Area.

It is believed that power companies would use thermal vents in the vicinity of the peak to tap the energy of the volcano.

At 10,781 feet, Mount Baker is one of the most visible peaks in the range. Its stark white glaciers can be seen from Seattle, and on a clear day you can see it from Mount Rainier, more than 100 miles to the south.

The volcano is part of the Cascade Volcanic Arc, a segment of the Pacific Ring of Fire, which includes 160 active volcanoes. It is the second-most active volcano in the range after Mount St. Helens, which erupted in 1980 with deadly effect.

Mount Baker has a less fearsome reputation. Even so, it has been active as recently as the mid-1970s, when its crater broke open and began spewing steam and ash clouds in to the vicinity causing concern to local residents, particularly those living below Baker Lake. The thermal activity prompted the temporarily closure from public access of the Baker Lake recreation area and to lower the reservoir’s water level by 10 meters.

Since then the peak has been quiet although seismic activity continues to be recorded below the mountain and it remains one of the most studied of the Cascade volcanoes.

Although it is impossible to say exactly how much energy could be obtained from the volcano the BLM has determined that the average viable capacity for a geothermal site in the 12 Western states must be at least 50 megawatts.

However, even if exploration of the chosen lands showed the geothermal potential to be high there are a number of issues power companies who wished to develop the sites would face. Any future geothermal plant would be located in an area of natural beauty where the environmental impact could be disastrous for the ecosystem that exists on the volcano’s slopes.

For example, the USFS has already stipulated that any development could not be built within 65 yards of the nesting sites of northern spotted owls and marbled murrelets, which have their breeding grounds in the area around Baker Lake.

Following the public consultation the USFS will determine whether the lands should be leased, leased with stipulations or whether they should be withdrawn from leasing altogether.

* Paul Willis, EarthTechling