The present agreements expire between the end of 2012 and the end of 2014.

The new deal, if approved by the California Public Utilities Commission, would extend the term for Geysers energy through 2021. Total capacity is expected to increase about 50 MW to a total of 425 MW from 2010 through 2017, dropping to a total of about 250 MW from 2018 through 2021.

“PG&E has been a leader in the use of clean geothermal power for half a century,” said Fong Wan, senior vice president for energy procurement at PG&E. “As our new contract indicates, we are committed to making this climate-friendly resource an important part of our growing renewables portfolio for many years to come.”