Our vision is to create a sustainable energy future for Arizona. To accomplish this, we must strike a balance between delivering reliable, affordable energy and being responsible stewards of the environment.

Carbon Management

Effectively reducing our carbon intensity and deploying a diverse, increasingly cleaner energy mix is good for our customers, our communities and the environment.

The APS 2017 Integrated Resource Plan (IRP) details our comprehensive plan to reliably and affordably meet customers’ projected energy needs, fulfill regulatory targets and management environmental impacts over the next 15 years.

We work to achieve a cleaner energy mix through efforts that include closing older coal units, increasing environmental controls at existing units, modernizing natural gas plants, using more renewable energy and increasing energy efficiency. In addition, the Palo Verde Generating Station, the nation’s largest carbon-free energy resource, provides more than 70 percent of Arizona's carbon-free energy.

The IRP outlines planned reduction of coal generation from 21 percent in 2017 to 11 percent of the APS generation mix by 2032 while increasing renewable generation by approximately 50 percent.

Increased environmental controls contribute to a cleaner energy mix. The Four Corners Power Plant will see a 90 percent reduction of nitrogen oxide (NOx) levels after the installation of selective catalytic reduction technology in 2018.

Flexible natural gas capacity will help us integrate the nearly 5,000 MW of renewable energy capacity that will be on our system by 2032. The $500 million project to modernize our Ocotillo Power Plant in Tempe, Arizona, will support our ability to maintain a balanced, reliable power supply, particularly during periods when renewable resources ramp up or down, or are not generating power. In addition, with the installation of the five new, highly efficient gas-fired turbines, the plant’s NOx and carbon monoxide emissions rates will be reduced by 50 percent while more than doubling the plant’s energy generation capacity.

Aps Energy

Living in the desert, we want to take advantage of our most abundant resource: the sun. By the end of 2017, our system had over 1,600 megawatts of renewable energy capacity, of which approximately 1,300 megawatts came from solar resources. Flexibility is critical as we integrate private rooftop solar and other variable resources while maintaining reliability and keeping costs low for customers. Approximately half of our anticipated new energy growth will be realized through the increased use of renewable energy and energy efficiency. We have committed to invest $10 million to $15 million per year for a three-year period in the APS Solar Communities program, which will provide access to solar for limited-income and moderate-income customers.

APS has achieved significant progress with our efforts to reduce carbon emissions and make our diverse energy mix cleaner. In addition to coal retirement, we have increased carbon avoidance through an growth in solar generation (both owned and purchased), energy efficiency programs for our customers, and improvements made to our facilities and vehicle fleet to reduce emissions. Through these combined efforts, in 2017 APS avoided 5.1 million metric tons of carbon dioxide emissions.

Learn more about Carbon and Air Emissions.

Water Resources

As an energy company operating in the water-constrained Southwest desert region, APS is challenged to maximize our use of recycled water resources and minimize our use of non-renewable water resources, such as groundwater. Effectively managing water helps us ensure that a sustainable supply is available to produce reliable energy for our growing customer base well into the future.

Over many years of carefully managing our water resources in the Arizona desert, APS has become an expert in what has come to be known as the water-energy nexus. Utilities in Arizona are aware that efficient use of water is important to all water users in our state. Currently less than 3 percent of the Arizona water budget is used for power generation, well below the national average.

Non-renewable groundwater is the most at-risk water supply in Arizona, and APS has committed to a long-term goal of reducing groundwater use. In 2017, we reduced groundwater use by 14 percent compared to 2014 usage, surpassing our goal of a 10 percent reduction. As we continue to implement our water-management strategies, we project reductions of 45 percent by 2020 and 60 percent by 2026 (compared to the 2014 baseline).

Water use

We are committed to preserving the long-term quality and availability of our water resources. As power plants get older and are eventually retired, we plan to replace these more water-intensive units with newer, more water-efficient technologies.

A prime example of this strategy is a project to modernize our Ocotillo Power Plant, which uses 100 percent groundwater for cooling. We are replacing two 1960s era water-intensive steam units with five new, quick-start turbines with hybrid cooling towers. The new cooling towers will use much less water for cooling than the old steam units, reducing water consumption at the plant by more than 80 percent.

Additional groundwater conservation measures have been implemented through an initiative focused on the reliability of well and pumping equipment that has increased operational performance and reduced water consumption. For example, installing new wells with variable frequency drives allows more precise withdrawals from wells with no water waste. These measures helped us achieve a 96 percent rate of reliability for well and pumping equipment in 2017.

Our usage of reclaimed water sets an industry standard. Reclaimed water accounted for 72% percent of the water used in our generating facilities in 2017. Key to our water resource strategy is Palo Verde Generating Station, an internationally recognized leader in the use of reclaimed water for power generation. As the nation’s only nuclear plant not located on a body of water, every year Palo Verde recycles more than 20 billion gallons of wastewater from surrounding municipalities to cool the plant.

Learn more about Water Resources.

Email Alerts


Enter the code shown above.