Summer of 2017 Rewrote APS Energy Records

Energy use records, new technologies and a historic solar eclipse
defined the season

PHOENIX–(BUSINESS WIRE)–When the sun wasn’t being obscured by the moon this summer, it produced
enough heat for customers to break Arizona energy records, even as new
technologies worked to increase efficiency and reliability across the
Grand Canyon State.

Microgrids and large batteries came onto the scene in Arizona in 2017,
delivering increased reliability to millions of APS customers. This
reliability was reinforced by a new operating system – the Advanced
Distribution Management System (ADMS) – adopted by APS to increase grid
resiliency and shorten outage times for customers. In addition, APS
rebuilt parts of the grid after the summer wildfire season, and ensured
power to customers during a historic solar eclipse. While the eclipse
cut solar output by nearly 50 percent at its height, APS was fully
prepared and relied on its diverse resource mix, including carbon-free
nuclear power from Palo Verde Generating Station, advanced technologies
and quick-start natural gas-fired plants, to provide power to customers.

“Driving past a microgrid or energy storage unit, many customers
wouldn’t look twice, but those technologies are playing an increasingly
important role in delivering efficient energy on the hottest days of the
year,” said Jacob
Tetlow, APS Vice President of Transmission and Distribution
Operations.

June 2017 was the third hottest June ever recorded in the Phoenix metro
area, with June 20 topping out at 119 degrees. While hot summers are
nothing new to Arizona, on that day APS customers set an all-time record
peak demand of 7,367 megawatts, breaking the previous record of 7,236 MW
set in 2006. To meet this demand, APS relied on a diverse mix of
traditional resources, as well as advanced technologies.

Microgrids in Yuma and North Phoenix provided grid resiliency on the
hottest days of the year by kicking on at critical-usage times and
providing power to surrounding communities. Energy storage units in
Surprise and Buckeye provided nighttime power to solar customers and
helped ensure reliability during the August 21 solar eclipse which
reduced solar output substantially.

“Our customers’ needs are changing, technology is progressing and APS is
ready for both,” said Tetlow. “Thoughtfully implementing these
technologies makes our grid smarter, faster and stronger.”

The future looked even brighter this summer as APS announced plans to
break ground on battery storage units in Punkin Center, AZ. The
batteries will take the place of rebuilding 20 miles of power lines,
providing even greater reliability to the growing community. The project
is one of the first of its kind in the nation and is slated to be
operational by next summer.

APS also experienced its first summer with its Advanced Distribution
Management System or ADMS. ADMS is an advanced operating system that
provides grid operators increased visibility and accessibility to power
lines across the state. The ability to remotely control lines played an
important role in APS’s response to the Goodwin fire in June. APS crews
worked long hours, coordinating with state and local officials, to
de-energize power lines and help ensure the safety of both first
responders and local residents. After fire crews from across the country
extinguished the blaze, APS quickly and safely reenergized lines as
residents returned to their homes and businesses.

While the summer of 2017 will surely go down in the history books, the
technology tested will lead the way to Arizona’s energy future.

APS
serves about 2.7 million people in 11 of Arizona’s 15 counties, and is
the Southwest’s foremost producer of clean, safe and reliable
electricity. Using a balanced energy mix that is nearly 50 percent
carbon-free, APS has one of the country’s cleanest energy portfolios,
including both Palo Verde Generating Station and renewable energy. The
company is also a proven leader in introducing technology and services
that offer customers choice and control over their energy consumption.
With headquarters in Phoenix, APS is the principal subsidiary of Pinnacle
West Capital Corp. (NYSE: PNW).

Contacts

APS
Media Contact:
Annie DeGraw, 602-250-4370
Analyst
Contact:
Stefanie Layton, 602-250-4541
Website: aps.com/newsroom