Green light for Arizona utility’s solar plan

April 5, 2010

Arizona power utility Tucson Electric Power has been given the go-ahead to develop 33 megawatts of new solar generating capacity, through power purchase agreements and new company-owned systems.

The Tucson-based company had applied for clearance from the Arizona Corporation Commission for a PPA from a new 25 MW photovoltaic facility at a Tucson Water site northwest of the city.

It also sought permission to buy power from a 5MW concentrating solar power (CSP) plant being developed at the University of Arizona Science and Technology Park.

The development of these local renewable resources is exactly what the Commission hoped to encourage through the Renewable Energy Standard” - Kris Mayes, ACC

Both projects are expected to be completed by January 2012.

The utility is also planning to build 3.4MW of company-owned solar PV arrays as part of its effort to meet Arizona’s Renewable Energy Standard, which requires utilities to source 15% of their power from clean power projects by 2025.

Commenting on the approval by the Commission, TEP Chairman, President and CEO Paul Bonavia, said: “With the ACC’s support, we can forge ahead with partnerships that support the development of what will become Southern Arizona’s largest solar energy resources.

“We also can add to our own solar resources in ways that will ultimately make solar energy more accessible and affordable for our customers.”

The 25MW PV array will be a ground-mounted system owned and operated by Fotowatio Renewable Ventures. The array will be built on 305 acres of Avra Valley land, leased from the Tucson Water company.

The 5MW CSP plant will be owned and operated by the Bell Independent Power Corp., and will represent the first plant of its kind in the Tucson area. The system will use parabolic mirrors to focus sunlight on a heat transfer and storage system to generate pressurized vapor to drive a turbine.

“The development of these local renewable resources is exactly what the Arizona Corporation Commission hoped to encourage through the Renewable Energy Standard,” said ACC Chairwoman Kris Mayes.

“I’m pleased to see that TEP will be moving forward with such significant solar projects.”

Community Solar Program

TEP, which is a subsidiary of UniSource Energy that serves 400,000 customers in southern Arizona is also currently developing 1.8MW of solar capacity to build on its existing 4.6MW portfolio, with plans for a further 1.6MW of developments later this year.

The utility is proposing a new “Bright Tucson” Community Solar Program, which will allow customers to purchase 150-kilowatt-hour blocks of solar energy. Each block would cost $3 on top of monthly bills.

The scheme is yet to be approved by the Commission.

Flagstaff pilot

Friday also saw the Commission approving a pilot project in which Arizona Public Service Company, part of Pinnacle West Capital Corp, will develop a $10.8 million solar installation program for 200 homes in Flagstaff.

The utility based in Phoenix will also install solar water heaters for 50 homes and small-scale, stand-alone wind turbines on approximately six properties in a limited distribution area in northeast Flagstaff under the initiative.

Ms Mayes said: “This pilot will measure the impact of concentrating a number of solar systems in a given area, and will likely prove that solar energy reduces the need for additional utility infrastructure, thus saving all ratepayers money over time.”