Background

The project will provide electricity to Tucson Electric Power Company (TEP), an Arizona corporation and principal subsidiary of UniSourceEnergy, which serves more than 400,000 customers in southern Arizona, covering the city of Tucson, as well as numerous smaller towns and unincorporated areas in Pima and Santa Cruz Counties. The electricity
generated by the project will be consumed mainly in the larger Tucson metropolitan area.

In November 2006, the state regulatory body for utilities, the Arizona Corporation Commission (ACC) approved the current Renewable Energy Standard and Tariff (REST), which requires regulated electric utilities in Arizona to generate 15% of their energy from renewable resources by 2025.

At the end of 2010, TEP was generating most of its power from coal (69.6%) and natural gas (30.2%), with less than 1% coming from REST eligible renewable sources. This project is part of TEP’s plan to comply with state regulations.

Description

The project consists of building a solar photovoltaic energy plant using thin film amorphous silicon modules mounted on a fixed-tilt racking structure based on azimuth positioning with a nameplate capacity of approximately 5.1-megawatt (MWAC) of electricity. The solar project will occupy 38.5 acre parcel in the Solar Zone of the UASTP and will be executed under an engineering, procurement and construction (EPC) contract. All the energy generated will be purchased by TEP and will primarily be used to serve the metropolitan area of Tucson. The interconnection point with the TEP grid is on site with the entire
infrastructure already installed.

Benefits

The project will displace greenhouse gases produced by traditional fossilfuel based energy generation and thus improve air quality, while providing the citizens of Tucson, Arizona, with a safe, reliable energy alternative. Estimated emission improvements include the displacement of over 7,700 metric tons of carbon dioxide (CO2), 28 metric tons of
nitrogen oxides (NOx) and 44 metric tons of sulfur dioxide (SO2) per year. In addition, the project will form part of the UASTP Solar Zone, a research facility designed to enable various solar technologies to perform side by side, under identical operating conditions, in order to assess the most optimal technology and/or technological mix for solar energy production in the U.S. Southwest.