As per the deal, Calpine will acquire NAES, an independent supplier of power to commercial and industrial retail customers, for purchase price of $800m.

The transaction also includes payment of an estimated $248m of net working capital at closing.

 Noble co-CEOs Jeff Frase and Will Randall said in a joint statement: "The sale of NAES substantially completes the $2bn capital raising initiative that we announced in June.”

Proceeds from the sale will be used by Noble Group to reduce debt and to fund growth opportunities to strengthen business.

Calpine president and CEO Thad Hill said: “The acquisition of this well-regarded organization known for providing sophisticated customers with highly customized products is a natural fit with Calpine’s customer-centric culture and will allow us to build upon the success we have experienced since our entry into retail last year through the Champion Energy platform.

“In addition to expanding our retail customer sales channels and product offerings, we will more than double the volume of retail load we are capable of serving across the country from our complementary wholesale power generation fleet.”

Scheduled to be completed in December 2016, the transaction is subject to approval by Noble shareholders, expiration of the Hart Scott-Rodino waiting period and approval of the US Federal Energy Regulatory Commission.

Currently, Calpine has about 84 power plants in operation or under construction with a combined generation capacity of more than 27,000MW.

Image: Noble Group will divest its US energy unit to reduce debt. Photo: courtesy of xedos4/