Updated: April 2020

To improve grid resiliency and our ability to prevent and respond effectively to weather-related outages, we implemented a series of measures in 2019 that hardened the power grid. Each summer, Arizona’s monsoon brings heavy winds and rain that can significantly impact our operations. We perform routine preventive and predictive maintenance on a regular, on-going, basis, using a variety of tools and resources, including infrared equipment to locate “hot spots” on our transmission and distribution system. These hot spots can be indicators of grid infrastructure that is failing or likely to fail. Our crews then further inspect the targeted equipment and replace or repair components as needed. Crews also have used the cooler months to install more steel power poles as “stopper poles.” This further improves grid resiliency by helping to prevent longer stretches of traditional wooden power poles falling down or breaking during high wind events, including our notorious monsoon winds.

The electric transmission and distribution system is evolving, and we are working to remain at the forefront of innovation in our rapidly changing industry. We plan to continue to invest in new grid technologies, system upgrades and related management systems through a number of project initiatives.

There are several key drivers behind our investments in a modernized transmission and distribution system. We pursue continual improvement in our safety, operational reliability, power quality and customer value. Integrating advanced transmission and distribution system technologies enables us to build a modern, flexible grid that enhances our operational capabilities and provides our customers with a new generation of tools and services. Modernizing the transmission and distribution grid yields greater efficiencies, including improved work management processes for our employees through the use of mobility solutions. Increased penetration from residential solar and battery storage systems requires us to develop new and better ways to manage power quality on our system. And the grid must evolve to support the emerging technologies and options that our customers increasingly demand.

The high level of distributed energy resource (DER) penetration on our grid pushes us to innovate in order to optimize our grid resources to maintain reliability. For example, we are the first utility in the nation to leverage our advanced metering infrastructure (AMI) network for two-way grid communications. Our AMI network has been installed on 98% of APS electric customer meters.

Microgrids are small-scale power generating facilities installed at customer locations that can provide backup power to the customer in the event of a grid outage and deliver peaking service and frequency response to APS that benefits additional customers.

We can share in the costs of developing microgrids with our customers, which results in cost-effective economic deployment of new grid resources. A microgrid’s fast-acting capabilities also enhance grid resilience and flexibility by providing important peak resources and ancillary services such as frequency response, which can lessen the occurrence and impact of power outages.

Through an innovative relationship with the U.S. Department of the Navy, we operate an ultra-low emission, 25-MW microgrid at the Marine Corps Air Station (MCAS) Yuma. The system, which went into service in 2016, provides 125% of the backup power needed by the base in the event of a grid disruption, enhancing reliability and security at the base, and allows the base to add more capabilities in the future.

We also own and operate a 13-MW microgrid at the Aligned Data Centers campus. The microgrid was deployed in 2016 within the heart of the Phoenix metro area. Like the MCAS Yuma microgrid, the cost-shared microgrid at Aligned provides peak generation and frequency response to the APS system, in addition to backup power for the data center in case of an outage. Both microgrids have successfully responded to over 100 grid events since being placed in service.

Microgrids offer great potential for developing grid innovation. For example, we have two patents pending on the systems developed in-house that enable our microgrids to perform autonomous frequency response.

The microgrid at Marine Corps Air Station Yuma can supply complete backup power to the base in case of a grid outage.

In our constant quest to improve reliability for our customers, in just 10 short years we have gone from using push pins and paper maps to track outages and other system issues to utilizing a state-of-the art outage management system with mobile device capability and advanced fault locating features. The Advanced Distribution Management System (ADMS) Project is a major initiative that will increase operator control and overall distribution system situational awareness to more effectively manage distributed energy and smart grid technology. The project allows our customers to benefit from improved system reliability and increased outage information and enables the use of more customer-sided technology. The ADMS Project and future initiatives are a big step toward integrating flexible and dynamic technology that will allow us to operate the grid of the future.

Our unmanned aircraft system (UAS) program continues to grow and provide benefits to our customers. UAS technology, commonly referred to as “drones,” allows field personnel and engineers to work safer, collect hard-to-reach imagery, and evolve engineering practice at lower costs than traditional methods. We have worked to ensure that our UAS program meets all Federal Aviation Administration requirements. UAS-mounted thermal imaging and high-resolution sensors are used to inspect overhead lines, photovoltaic panels, boiler and heat recovery steam generator tubes, and concrete containment domes and cooling towers at Palo Verde to track performance and determine the overall health of systems. In addition to providing improved inspection data, UAS help us respond more quickly to issues affecting the grid, such as storm damage. They are also used to map overhead lines on the grid and holding ponds at our coal plants for engineers to determine best courses of action. In the future, they may be used to survey remote transmission and distribution lines using machine learning to detect anomalies, reducing the cost to perform annual inspections for proactive maintenance.