The Navajo Generating Station near Page will close in December 2019 unless a new owner is found. This has left the Central Arizona Project looking for new sources of electricity.

A plan by the operators of the Central Arizona Project to look for new sources of electricity beyond the coal-fired — and possibly soon-to-close — Navajo Generating Station near Page is raising questions from federal officials.

The move comes as the Central Arizona Water Conservation District, which manages the system, is soliciting bids for electricity needed to pump the water from the Colorado River up through Maricopa, Pinal and Pima counties. District spokeswoman DeEtte Person said the bids on the table include a solar project as well as buying power from Salt River Project.

District board members are set to consider the proposals Thursday.

But in letter late last week to the CAP board, Timothy Petty, assistant secretary for water and science for the Department of Interior, said his agency, which through the Bureau of Reclamation owns part of the plant, believes a 1968 law “appears to authorize NGS as a source of power for the project.” And that, he wrote, means the board needs to answer some questions.

What gives the federal government some say in all this is that it was Congress that appropriated funds for the Central Arizona Project and the federal portion of the power plant.

The private utilities owners of NGS have concluded it’s no longer financially feasible to keep the plant operating. State lawmakers earlier this year approved a tax break for the plant in hopes of luring a buyer but none has emerged. It is scheduled to close in 2019.

But that, said Petty, still leaves the federal law.

“While the Department (of Interior) recognizes that many circumstances have changed since passage of the 1968 Act ... it currently believes that the 1968 Act remains the applicable governing authority and must be addressed in any decision relation to future sources of (Central Arizona) Project power,” he wrote.

Person, for her part, is downplaying the bids the CAP is seeking. “It was our understanding that NGS is closing,” she said.

“It’s still our understanding that NGS is closing because there hasn’t been a buyer that’s come forward,” Person continued. “In the meantime we’ve been looking for power and trying to do our due diligence in lining up the best power sources at the best price to make sure we’re ready for when we don’t have that power any more.”

But Person said she does not believe her board believes that it is obligated to continue buying electricity from NGS if it can find cheaper power elsewhere.

“There’s certainly plenty of room in the (energy) portfolio should an owner come forward for NGS,” she said. “If there was a new owner, they could certainly put forth their proposal to us for us to buy our power from them.”

NGS provides between about 75 percent of the electricity for the CAP, with some of the other power coming from hydroelectric dams.

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