LAKE COUNTY — A Thursday afternoon ribbon cutting at the Geysers facility on Cobb Mountain kicked off Calpine”s multi-million dollar plan that will mean new drilling and revamping existing wells to provide more power during the next five years.
Calpine is the nation”s largest renewable geothermal power provider, generating 725 megawatts of renewable geothermal energy at the Geysers operations alone. That powers 725,000 households throughout California and up to the Oregon border.
The ceremony took place at the north end of the Geysers, symbolizing the company”s intention explore that area for new drilling sites.
“There”s been no major expansion for quite a while at the Geysers,” said Joe Ronan, senior vice president for government and regulatory affairs. He added that the north end of the Geysers is largely unexplored and holds ample opportunity for drilling.
Briefly explained, the Geysers operations use the power of steam from the earth”s crust to generate renewable energy. Where the earth”s crust is particularly thin, magma turns water trapped in minute cracks in a hard layer of rock into steam. Geological experts and engineers determine the ideal location to drill wells to tap the steam and use it to power generators in plants placed strategically in the area.
“That”s one of the biggest things the Geysers has going for it,” said General Manager Dave Jackson. “Solar is there when the sun”s out, wind energy is there when the wind”s blowing, but the Geysers are there 24 hours a day, seven days a week. We”re very proud of that. When California needs us the most, we”re here.”
The plan involves 90 new or reworked wells, said Ronan. That would generate an additional 80 megawatts, or enough to power 80,000 more homes.
In addition to increasing steam production, a two-year drilling program would also seek to identify new sources of geothermal power and rebuild eight older geothermal turbines.
An example is well pad GDC-31, where the ribbon cutting ceremony was staged. General Manager Dave Jackson said the well had dropped to a production 40,000 pounds per hour of steam. After a recent cleaning and reworking, the well was back up to producing 177,000 pounds per hour, an approximately eight megawatt producer on its own.
Lake and Sonoma counties renew the reservoir through the injection of treated sewer water. Jackson explained that in the 1980s and 90s, too many companies drilled in the area and depleted the water in the reservoir by an average of 11 percent per day. “It was like too many straws in one bowl,” he said. The operations today are helping to restore the reservoir.
A portion of the steam that comes from the earth is re-injected as water, but 30 to 60 percent of that is subject to evaporation, said Jackson.
Calpine has been in bankruptcy since December of 2005, said Jackson. “This is a good sign that we”re well on our way to emerging,” he said. “It”s a sign of investor confidence. This doesn”t happen without the bankruptcy committee, and they are solidly behind our expansion and the capitol we”re infusing into the geysers.”
Contact Tiffany Revelle at trevelle@record-bee.com.
