Negotiators trying to hammer out a contract to keep an upstate New York nuclear power plant financially viable have been given a three-week extension by state regulators.

Constellation Energy Nuclear Group and Rochester Gas & Electric had faced a Jan. 15 deadline to complete talks for a reliability support services agreement (RSSA) that would likely raise rates for customers.

The New York Public Service Commission in November ordered the RSSA in an effort to save the 580-MW Ginna Nuclear Power Plant on Lake Ontario, 20 miles east of Rochester. NYISO and RG&E said the plant is needed until at least 2018 to maintain system reliability in western New York.

Constellation said the plant has lost $100 million over the past three years and would be mothballed without better financial terms. The RSSA would provide electricity to RG&E at a guaranteed price when called upon.

The two companies jointly asked for an extension until Feb. 6.

“Although significant progress has been made, GNPP and RG&E have not yet finalized an agreement that satisfactorily resolves all of these issues,” the petitioners wrote. “A brief extension will permit GNPP and RG&E to continue to work together in an attempt to develop a more considered RSSA that best satisfies the commission’s requirements as well as the needs of GNPP, RG&E and all interested parties.”

While negotiations continued during the original 60-day period, PSC staff requested financial information from the companies. Ginna and RG&E have asked that the commission keep those documents confidential as they contain protected trade information. That has led to complaints from consumer groups who seek more disclosure.

“Despite the potential for major cost increases for the public in the Rochester area, this PSC proceeding has been marked by an unusual lack of information available to the public,” the Alliance for a Green Economy and the Citizens’ Environmental Coalition wrote in a Jan. 13 letter to the commission. “Today we are writing to flag this problem for the commission as an issue of major concern.”