TEP Ranks Among Nation’s Top Utilities for Expanding Energy Storage

TUCSON, Ariz.–(BUSINESS WIRE)–Tucson Electric Power (TEP) has developed energy storage systems at a
scale that ranks among the utility industryÔÇÖs leaders, according to a
report released today by the Smart Electric Power Alliance (SEPA).

TEP was ranked second in the nation for per-capita additions to its
energy storage resources in 2017 with 50 watts per customer. SEPA also
ranked TEP third in the nation for new energy storage capacity for
adding 21 megawatts (MW) of battery storage systems to its local
electric grid.

ÔÇ£Energy storage systems are among the technologies weÔÇÖre using to build
a stronger, cleaner and more reliable electric system for our
customers,ÔÇØ said David G. Hutchens, TEPÔÇÖs President and Chief Executive
Officer. ÔÇ£We will need both storage and advanced, flexible generating
systems to maintain reliable service as we expand our use of renewable
resources.ÔÇØ

Energy storage systems can boost power output levels quickly to help
maintain the required balance between energy demand and supply. They
also can be used to store the output of wind and solar power systems for
use during periods of high demand, adding versatility but also cost to
renewable resources.

TEP added two 10-MW battery systems last year:

• A lithium nickel-manganese-cobalt storage system at a TEP substation
  near Interstate 10 and West Grant Road, built by a subsidiary of
  NextEra Energy Resources
• A 10-MW lithium titanate oxide storage facility linked to a 2-MW solar
  array at the UA Tech Park southeast of Tucson, built by E.ON Climate &
  Renewables

Both systems are now helping to maintain reliable service for customers
during periods of high energy demand by supporting stable voltage on
TEPÔÇÖs local distribution grid.

TEP also is participating in a research and development project with
Chicago-based IHI, Inc. Energy Storage (IHI), which completed a 1-MW
lithium ion energy storage system at the site of TEPÔÇÖs Prairie Fire
Solar Array, a 5-MW system located near Interstate 10 and East Valencia
Road. The IHI system is charged with energy generated by TEPÔÇÖs solar
array.

Additionally, TEP also announced plans for a new 30-MW battery storage
system that will be paired with a 100-MW solar array. Both systems are
scheduled to come online by 2019.

TEP is working to deliver at least 30 percent of its power from
renewable resources by 2030, doubling the stateÔÇÖs 2025 goal. TEP
anticipates adding an additional 800 MW of new renewable capacity,
boosting its total renewable energy portfolio to approximately 1,200 MW.
Nearly 13 percent of TEPÔÇÖs power came from renewables last year, well
above ArizonaÔÇÖs 7 percent requirement for 2017.

TEP provides safe, reliable electric service to approximately 422,000
customers in Southern Arizona. For more information, visit tep.com.
TEP 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. For more information,
visit fortisinc.com.

Contacts

Tucson Electric Power
Joseph Barrios, 520-884-3725
[email protected]