2 More Western Utilities Move to Close Coal Plants Early, Shifting to Renewables and Storage

Two more utilities in Arizona and Colorado are moving to
accelerate closure of coal plants and replace them with renewable
energy backed by batteries, joining a broader push in both states
to shift to more cost-effective clean energy optionseven in the
absence of state mandates. 

Tucson Electric Power on Friday released a long-term energy plan
that calls for closing its remaining coal plants by 2032, on the
way to 70 percent renewables by 2035. Arizona’s biggest utility,
Arizona Public Service (APS), recently announced its own
carbon-free energy by 2050 plan, despite a lack of state mandates
requiring such a transition. 

Meanwhile, Colorado Springs Utilities said it would close its
remaining coal plants by 2030. Along with accelerated coal closure
plans from two other Colorado utilities, this will leave
multi-state utility Xcel Energy, which has committed to 100-percent
carbon-free electricity by 2050, the only one to keep coal plants
open past the end of the decade.

Colorado wants to get half of its power from renewable by 2030
and 90 percent by 2050.

Arizona’s transition from coal to renewables and batteries

Tucson Electric Power’s 2020
Integrated Resource Plan 
calls for a steady phase-down of
its coal-fired Springerville Generating Station: the plant would
start operating on a seasonal basis in 2023, close down one of its
425-megawatts unit in 2027, and the other remaining unit by

At the same time, the plan would see TEP adding 1.7 gigawatts of
solar, 850 megawatts of wind and nearly 1.4 gigawatts of energy
storage by 2035. Alongside a big boost in its energy efficiency
efforts, TEP says the plan would allow it to avoid building any new
natural gas plants. 

TEP, which serves about 430,000 customers, had already exited
the Navajo Generating Station coal plant in Arizona, owned by
Arizona utility Salt River Project, which closed
last year
. It is also planning to exit the San Juan and Four
Corners coal plants in New Mexico, owned by utilities Public
Service Co. of New Mexico and APS, respectively. Both plants are in
the Navajo Nation, which has asked Arizona
 to require the utility to pay up to $62 million to
compensate for resulting economic losses. 

Springerville’s remaining two units are owned by electric
cooperative Tri-State Generation and and Salt River Project.
Tri-State, which serves 43 electric co-op members and more than 1
million people in four Western states, plans
to abandon coal
 and add more than 1 gigawatt of utility-scale
renewable generation to its portfolio by 2030.

APS has committed to 100-percent
clean power by 2050
, including an interim target of 65 percent
by 2030. That target will make use of the roughly 25 percent of its
capacity provided by the Palo Verde nuclear power plant, as well as
45 percent renewable energy, largely solar power. 

The Arizona Corporation Commission (ACC) hasn’t imposed any
clean energy or carbon reduction mandates on the state’s
utilities, and it allowed a moratorium
on new natural gas
 power plant construction to lapse
last year
. But falling prices for solar power and lithium-ion
batteries in the sun-soaked state have made that
combination a
cost-effective alternative
 to dispatchable fossil-fired power
— although a fire
at APS’s McMicken battery
 facility last year has halted new
battery installations until the state concludes an investigation
into broader safety issues. 

Colorado utilities moving toward 100-percent clean energy 

Friday’s 7-2 vote by the Colorado Springs Utilities (CSU)
Board approves a plan to close its 208-megawatt Martin Drake coal
plant by 2023, 12 years earlier than initially planned, and to shut
down its 283-megawatt Ray Dixon coal plant by 2030. 

The plan won approval against alternatives that would have
replaced Martin Drake’s coal generators with permanent natural
gas generation, relying instead on temporary natural gas generators
until new transmission lines can be built to replace its capacity.
Under its 2020 Electric Resource Plan, the municipal utility
serving about 222,000 customers will replace its 416 megawatts of
coal-fired power with about 500 megawatts of new wind energy,
about 150 megawatts of solar power and more than 400 megawatts of
battery storage. 

Colorado Springs’ decision comes on the heels of two other
Colorado utilities pledging early retirements of their coal plants.
Earlier this month, the Platte River Power Authority decided to
shut down its 280-megawatt Rawhide coal-fired plant by 2030, or 16
years ahead of its previous schedule. And in January, Tri-State
said it would close its remaining units at the Craig coal plant in
2030, as part of its broader decarbonization plans. 

These decisions come as state leaders are considering a push
beyond its mandate for 50 percent renewables by 2030 and 90 percent
by 2050 signed into law last year. Gov. Jared Polis won the 2018
election on his call for the state to adopt a 100-percent
renewables by 2040
 target, and continues to press lawmakers for
a more aggressive policy. 

Xcel Energy, which owns Public Service Co. of Colorado, the
state’s biggest utility with about 1.4 million customers, has
pledged to reduce carbon emissions 80 percent by 2030 and 100
percent by 2050
, and plans to close its last two coal-fired
power plants in
Minnesota by 2030

In 2018, Public Service Co. submitted a plan to replace
660 megawatts of coal
 generation at its Comanche coal-fired
power plant with 1,131 megawatts of wind, 707 megawatts of solar PV
and 275 megawatts of battery storage, and won record-low
price contracts
 for battery-backed renewables in 2018. But it
hasn’t yet altered plans to keep the 750-megawatt Comanche 3 coal
plant operating through 2070, or to keep the 552-megawatt Pawnee
coal plans running until 2041. 

Source: FS – GreenTech Media
2 More Western Utilities Move to Close Coal Plants Early,
Shifting to Renewables and Storage