In Iceland, giant ducts carry superheated steam from within a volcanic field to turbines at Reykjavik Energy’s Hellisheidi geothermal power plant.Brennan Linsley/The Associated Press
This is part of an eight-week series on clean energy.
For Vancouver-based Alterra Power Corp., today's big geothermal energy opportunities lie outside Canada. Publicly traded renewable energy specialist Alterra operates two geothermal plants in Iceland with a total capacity of 172 megawatts and a 23-megawatt-capacity facility in Soda Lake near Reno, Nev. It owns the latter outright and the former with Icelandic pension funds.
Alterra's largest and most promising new geothermal development is the Mariposa project in Chile, which CEO John Carson says could be the country's premier known geothermal resource. Located south of Santiago, Mariposa has an inferred capacity of 320 megawatts. Alterra is preparing for large-scale production drilling next fall. Its partner on the project is Manila-based geothermal producer Energy Development Corp., which is contributing about $60-million.
Unlike wind and solar power projects, which can go anywhere, geothermal works only in certain places due to the limits of existing technology, Mr. Carson explains. "Iceland is a unique area where the strong heat of the Earth is very apparent and very easy to get to."
Research wells drilled in Canada decades ago found the right temperature for geothermal, Mr. Carson says. In the zones that were drilled, though, there wasn't enough permeability in the rock around the drill holes for water to trickle in and turn into steam sufficient to power a plant.
"Where there's temperature, one could pretty well be certain that there are good permeable zones," Mr. Carson says. Although British Columbia has no proven geothermal wells, Mr. Carson sees potential to develop large-scale zones if the next round of exploratory drilling there hits pay dirt.
"It's contagious," he says, stressing that any such development is years away. "Once you've got an area that's somewhat proven, certainly it's going to attract others, and then you'll see these massive fields built out such as the Imperial Valley in California."