TEP power line approved for Sahuarita area despite opposition

The 4-0 commission vote, with one commissioner absent, means Tucson Electric Power can start construction on a line running up to 17 miles from an existing substation on the far southeast side. The utility has yet to choose one of two possible routes, but it says it expects to start construction on the line in 2028 and finish in 2029.

TEP has promoted the line as a vehicle for providing more power and more reliable electrical service to about 14,000 of its customers living in the Sahuarita area and other communities south of Tucson. Although the line will serve Sahuarita customers, most of it will pass through Tucson and unincorporated Pima County.

Officials of the group Save the Scenic Santa Ritas contend the power line was intended to benefit and serve the planned Copper World Mine in the Santa Rita Mountains southeast of Sahuarita.

They note that the Santa Rita Connection line would end at a new substation from which a separate line — approved by the commission in 2012 — would be built directly to the mine. They've expressed concerns that ratepayers will be subsidizing some of the mine's electricity use by shouldering the cost of the new line.

TEP officials deny these allegations, saying the mine will not get any power from this new line and that Copper World developer Hudbay Minerals Inc. will pay for its power costs by having to pay for the new line running from the Santa Rita Substation to the mine site in the mountains. 

At the July 8 commission meeting at which the Santa Rita Connection line was approved, Save the Scenic Santa Ritas Director John Dougherty said the new power line shouldn't be approved in part because the commission's Line Siting Committee, which recommended the line's approval, didn't disclose that the new line's endpoint and the Hudbay power line's starting point will be "co-located" at the new substation.

A switchyard that Hudbay had always planned to build in that area to transmit power to its new power line will now be combined with TEP's new substation, where the Santa Rita Connection line will terminate, TEP officials have said. Utility officials didn't disclose this fact until the day before the committee recommended the power line's approval back in late May.

"The failure to disclose raises significant concerns that ratepayers will be subsidizing Copper World's power," Dougherty told the commission. "By and large, this was completely obscured from the public."

The fact that the utility plans to co-locate the end of its new line and the long-planned line to the copper mine is irrelevant, the Line Siting Committee chairman countered in response to Dougherty.

"If anything, to co-locate those two facilities, there's less of an environmental impact," said Committee Chairman Adam Stafford.

It saves ratepayers' money to build one substation that could serve two power lines, added Meghan Grabel, an attorney who represented TEP.

"It really makes not just environmental sense, it makes ratepayer sense," Grabel said.

Reacting to the commission vote, TEP spokesman Joe Barrios wrote, "We're pleased that the Santa Rita Connection Project's certificate of environmental compatibility was approved by Commissioners. We look forward to construction of the project, which will improve service quality for customers in and around the Sahuarita and Green Valley areas."

In a statement, Hudbay said the commission's unanimous vote for the Santa Rita Connection line "highlights the project’s clear value in strengthening regional grid reliability and confirms that this is routine utility business. Hudbay will pay the full costs of infrastructure built to deliver power to Copper World for its exclusive use.

"This investment creates valuable colocation opportunities for the broader grid network, generating downward pressure on rates that benefits all other ratepayers," the company said.

Dougherty maintains his opposition. "This just continues to mislead the public on what’s going on here," he said. "The fact is they needed additional power in that area to be able to serve the mine."

He noted that a TEP official testified at a June 22 public meeting in Sahuarita that customer electricity demand in that area today is "at or approaching operating limits" for the existing electrical system.

"The Santa Rita Connection Project is a needed, publicly reviewed infrastructure project designed to address real and growing reliability needs in the Sarita and Green Valley area. Through our planning process, we've identified multiple circuits serving thousands of customers that are already at or approaching their preferred operating limits with continued residential and commercial growth expected," testified Stephen Eddy, TEP's public affairs director.

"This project is designed to improve redundancy, reduce the risk of outages, and ensure we can continue to serve the community as it grows, and today," Eddy said.

Barrios said that comment referred to various electrical distribution circuits that serve thousands of homes and businesses, but wouldn't serve the Copper World mine. So it's not accurate to say that the extra power from the new Santa Rita Connection line would serve the mine, he said.