UniSource Energy Services (UES) will build a stronger, more self-reliant resource portfolio for electric customers by expanding its generating resources with efficient natural gas plants and cost-effective renewable resources.
UES’ long-term strategy to build a more responsive, sustainable resource portfolio is described in its 2017 Integrated Resource Plan (IRP), recently filed with the Arizona Corporation Commission (ACC). The plan describes UES’ current resource portfolio, projects future energy needs, and outlines strategies the company will use to meet customers’ energy requirements over the next 15 years.
“As technologies develop and our customers’ energy habits change, we’ll add more reliable and responsive resources to continue providing safe and affordable service here in Arizona,” said David G. Hutchens, UES’ President and Chief Executive Officer. “Renewable resources, energy efficiency measures and new natural gas technologies will play an increasingly important role in our resource planning process.”
UES will continue efforts to reduce its reliance on the wholesale energy market by seeking cost-effective long-term power purchase agreements and low-cost generating resource acquisitions. The IRP anticipates the addition of approximately 175 megawatts (MW) of natural gas resources by 2022. In December 2014, the company acquired a 25 percent share of the natural gas-fired Gila River Power Station Unit 3, which can serve about one-third of UES customers’ peak energy needs.
UES is working to deliver 20 percent of its power from renewable resources by 2020, surpassing the capacity and deadline requirements that the company must achieve by 2025 under Arizona’s Renewable Energy Standard. UES expects to gain 5 MW of capacity this year with the completion of a new, company-owned photovoltaic solar array near Kingman.
To manage the intermittency and variability of an expanded renewable energy portfolio, the IRP describes potential investment in fast-responding generating resources over the next five years, including 37 MW of natural gas reciprocating internal combustion engines (RICE). RICE technologies offer an affordable way to manage power fluctuations associated with intermittent renewable resources.
Beginning in 2019, UES expects to add two small energy storage projects, which can boost power output levels more quickly than conventional power plants in order to maintain the required balance between energy demand and supply. Such systems are expected to decline in cost over the next several years and may provide a reliable solution for providing power during peak times and managing power fluctuations associated with renewable resources.
UES and project partners also will continue efforts to build a new 150 MW interconnection that would connect the electric grid in southern Arizona with electric facilities in northwestern Mexico. The Nogales Interconnection would support electric reliability, allow access to additional energy sources and support business growth in the region.
The IRP also describes how new smart grid technologies identified in the 10-year transmission and distribution plans would improve service reliability by providing increased system capacity and other benefits for the distribution network that delivers service throughout the state.
UES provides electric service to approximately 95,000 customers in Mohave and Santa Cruz counties. The company also provides natural gas to approximately 154,000 customers in northern and southern Arizona. For more information about UES, or to view a copy of the 2017 Integrated Resource Plan, visit uesaz.com.
UES and its parent company, UNS Energy, are subsidiaries of Fortis, Inc., which owns utilities that serve more than 3 million customers across Canada and in the United States and the Caribbean. To learn more, visit fortisinc.com.