For five years, Tucson Electric Power has designed, developed, procured and tested solar technology at the University of Arizona Science & Technology Park Solar Zone.

On Oct. 29, TEP celebrated the dedication of the seventh project at the UA Tech Park, raising the solar generating capacity of the Solar Zone to 22 megawatts, spread over roughly 170 acres. TEP owns two of the projects and purchases the energy through power agreements from the others.

The 1-megawatt Cogenra solar array, owned by Washington Gas Energy Systems, is now complete. The array deploys T14 ground-mounted, Dense Cell Interconnect technology.

The Solar Zone “is an incredibly important project for us because it allows us to evaluate different projects side by side, and that helps us determine what types of technologies can provide the most cost-effective renewable power to our system. This allows TEP to provide customers with something they want: sustainable energy at sustainable prices,” Philip Dion, TEP’s Senior Vice President of Public Policy & Customer Solutions, said during the event to celebrate the completion of Phase One of the Solar Zone.

“This is a great example of a public-private partnership that is done not only to benefit our customers at TEP, but to benefit our community.”

TEP tests new technology in the Solar Zone – the largest multi-technology utility-scale solar energy project in the country – under controlled conditions to determine which ones fare the best in Southern Arizona.

The Solar Zone was born after TEP and the UA partnered to develop a site that combined solar generation with robust research and testing. TEP negotiated the land leases, solicited the bids and handled all of the contracts on the various projects, while the UA, as the landowner, conducts the ongoing site management and upkeep.

Starting with its first 1.6-megawatt project, the Solar Zone has expanded now to seven technologies, owned by five different companies.

The five contracted projects have 20-year power agreements, so they will continue to feed the grid for quite some time to come. In addition to the seven major projects, TEP maintains a four-acre test field where it works to evaluate new technology, including electric storage.

“Technology is changing fast,” said Carmine Tilghman, TEP’s Senior Director of Wholesale, Fuels & Renewable Resources. “Evaluating new technologies at our test site will help shape our solar portfolio looking forward.”

The partnership between TEP and the UA brings the strengths and resources of both entities to the table.

“The UA Tech Park’s ongoing support and participation have been instrumental in the successful completion of our Solar Zone projects,” Tilghman said. “We’ve benefited greatly from the partnership. The UA is one of finest universities in the nation, and TEP is proud to have it as an energy partner helping us find alternative solutions for the future.

View a gallery of photos from the event on TEP’s Facebook page.

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