POWERFUL PROSPECTS

Arizona utilities already preparing for future energy needs

While old habits may die hard, Arizona utilities are embracing new ones to deliver clean energy that can power the state now and into the future.

Probably the boldest move toward where they are headed came in early 2020 when Arizona Public Service (APS), the state’s largest energy company, announced it was setting a goal to deliver clean, carbon-free electricity to its customers by 2050. That is no small feat when you consider APS serves more than 1.3 million homes and businesses in 11 of the state’s 15 counties. The goal includes a 2030 target of achieving a resource mix that is 65% clean energy, with 45% of its generation portfolio coming from renewable energy.

Salt River Project (SRP) is expanding its mix of clean, renewable energy sources as part of its plan to cut its carbon intensity 90% by 2050.

To help reach that target, SRP has set a goal of nearly half of energy sources to be carbon-free by 2025.

It’s worth noting that SRP was the first Arizona utility to use wind power when it bought 63 megawatts (MW) of power from the Dry Lake Wind Power Project in Navajo County in 2008.

More recently, it entered into a contract to buy enough wind energy from the Babbitt Ranch Energy Center north of Flagstaff to power 40,000 homes.

Tucson Electric Power (TEP) has set a goal of cutting its carbon emissions 80% percent by 2035. To help do this, more than 70% of its power will come from wind and solar resources.

On an annual basis, TEP already can produce about 30% of its power from renewable resources. One source comes from the Wilmot Energy Center, which includes a 100 MW solar array and a 30 MW battery energy storage system south of Tucson International Airport. The array generates enough power every year to serve more than 25,000 homes.

Before they all reach the milestones set for the future, they must shed some sources that won’t fit in. That includes moving away from using coal to create electricity. By 2031, APS expects to end all coal-fired generation—seven years sooner than previously projected. Add to that TEP plans to retire its two coal fired units at the Springerville Generating Station in 2027 and 2032.

Largely due to the age and complexity of coal plants (e.g., APS’s Four Corners Generating Station is more than 50 years old), the cost of electricity from these plants is no longer competitive with other power sources. While the price of electricity generated from aging coal plants is approaching $80 per megawatt hour

(MWh), new solar projects that include storage for nighttime generation are selling electricity for $14 to $25 per MWh.

But it’s not like someone will flip the switch by the end of the decade and this all will magically happen. APS already is at work.

For example, the utility is constructing its Agave Solar Plant in Arlington to meet a goal of being in service by summer. More than 400,000 panels will track the sun across the sky to generate 150 MW, which is enough energy to power 24,000 homes.

APS’s portfolio of additional new resources is expected to be ready for customers no later than 2024 and include maximum generated output of 425 MW by solar power, 238 MW by wind power and 635 MW by battery storage.

APS also is conducting an all-source request for proposals (RFP) through the 2025-2027 time frame in order to meet the power needs of customers with affordable, reliable electricity. It is seeking approximately 1,000 to 1,500 MW of resources, including 600 MW to 800 MW of renewable resources, which significantly will boost the amount of clean energy on the APS electric system. Proposed projects must be in service beginning in 2025 through June 2027.

The new resources that will come from the new RFP will add to the more than 1 gigawatt (GW) of clean energy secured through an all-source RFP and separate battery energy storage RFP issued in 2020. If you’re wondering what 1 GW really means for customers, APS estimates approximately 150,000 homes in its territory can be powered by this amount of energy. According to the U.S. Department of Energy, 1 GW is also the equivalent power of more than 3 million solar panels, 110 million LED light bulbs and more than 9,000 electric cars.

On the energy storage front, expect even more capacity to be added to what already has been achieved. These plans should keep things humming along after the sun sets and the wind dies down:

• SRP has added two battery energy storage systems as it moves toward 800 MW of energy storage by 2024.

• APS has set 2025 as its deadline for adding 850 MW of battery storage by 2025.

• TEP has set a goal of 1,450 MW in battery storage by 2035, according to its resource plan.

While the plans for the future may seem ambitious, keep in mind what Arizona’s utilities already have achieved to curb carbon emissions. They indeed are working to make a clean break from the power industry’s past.