The deal is an amendment to the existing McGinness Hills power purchase agreement (PPA) allowing Ormat to sell 63.7MW (net average annual capacity) from the complex.

Under this amendment, a new energy rate of $85.58/MWh with a 1% annual escalator will be fixed for the entire complex once Phase II enters commercial operation.

Ormat Technologies president and COO Yoram Bronicki said that the favorable performance of the reservoir and the PPA amendment give Ormat the ability to further expand this geothermal site.

"Phase I of our McGinness Hills geothermal power plant has been in commercial operation since June 2012 and the strength of the reservoir allowed the power plant to consistently produce more energy than what was contracted in the original PPA," Bronicki added.

"We are eager to continue development at the site which we hope to complete in mid-2015, as well as our work with NV Energy to deliver more clean, renewable power to Nevada."

The new rate is subject to approval by the Public Utilities Commission of Nevada.