TV meteorologist Mike Nelson on June 9 warned that Denver would be 10 degrees warmer than average that day. Thermometers indeed reached 91, as he predicted.
That same day, at a meeting of the Colorado Public Utilities Commission, Eric Blank was thinking about potential heat waves almost a decade into the future. Blank, the chairman of the commission, wondered how Xcel Energy’s electrical infrastructure would hold up if Colorado was part of a regional heat wave in the summer of 2030, with temperatures 8 degrees above average for a full week.
The utility commissioners were engaging in an exercise of what-ifs. They regulate Xcel, which is responsible for more than 60% of the state’s electrical sales, and Black Hills Energy, also an investor-owned utility. Periodically, those utilities must submit plans to show how they intend to meet demands. Part of the dance between regulators and utilities is creation of models that seek to depict future trends.
Planning for electrical generation—and the task of state regulators in protecting public interests—has become far more complex during recent decades.
A few decades ago there were far fewer moving parts. Back then, mostly it was a task of ensuring enough generation to meet the demand. That demand was always growing, as Colorado’s population grew at mostly 10% to 20% a decade and demand grew even more rapidly as we found ever-more ways to use electricity.
Now energy systems are in flux. Newer and more complex technologies have started arriving, and societal concerns have shifted. Those shifts in the last 10 to 15 years can be seen in Xcel Energy’s resource planning now being reviewed by state utility regulators.
“Today there are so many more options, so many other policy considerations,” says Erin O’Neill, the chief economist on the staff at the Public Utilities Commission.
“It’s not just about what costs the least. It’s about economic development and jobs—and, in the retirement of coal plants, the community impacts of just transition. It’s not that the economics and low cost don’t matter. But there are many other considerations.”
Chief among the policy considerations is how to reduce emissions. Xcel Energy in December 2018 announced a goal of reducing emissions 50% by 2030 and emissions-free electricity by 2050 in Colorado and other states where it operates.
Colorado legislators in May 2019 codified that promise into law, part of a comprehensive effort to decarbonize Colorado’s economy 50% by 2030 and 90% by 2050.
The 2030 goal will be far more easily achieved, largely because of the coal plant closures this decade. Xcel had previously announced plans to close two coal-burning units at the Comanche Station near Pueblo in 2022 and 2024. Earlier this year, as part of its current planning, it announced plans to close units at Hayden in 2027 and 2028. In addition, it plans to switch Pawnee, the plant near Brush, to natural gas by 2028.
In the next few years, Xcel expects to add “tons of wind, tons of solar, and tons of storage,” Matthew Larson, an Xcel attorney, told state legislators in May.
The energy path for Xcel and other utilities gets less clear as 2030 approaches. Chief among the giant questions is how storage will evolve. Lithium-ion batteries can store electricity for just a few hours. Utilities need storage that they can draw on for days, such as in the mid-February cold snap, or perhaps like that hypothetical heat wave of 2030 where temperatures spike 8 degrees for a week.
Hydrogen—one of the options being studied by Xcel—could store electricity for days but remains prohibitively expensive and has safety issues that must be resolved. More attractive at this point – and an idea being studied by Xcel – is molten-salt, which is already being used in various places in the world in conjunction with concentrated solar facilities. Still other possibilities are being examined.
Some of that storage could be in garages and driveways of Xcel customers themselves, as suggested by John Gavan, the utility commissioner from Paonia, at the recent meeting.
Gavan pointed out that Ford had recently unveiled an electric pickup, the Ford-150 Lighting. Ford plans to debut the model in 2022. Ford advertises that the batteries in the Lightnings will have the capacity to draw electricity from the grid or dispatch electricity to the grid.
In other words, the batteries could draw on the electricity from the grid when electricity is plentiful, especially when the wind is blowing and the sun is shining. Then, when demands on the grid surge or when renewable energy is sparse, the grid could draw on the battery of the pickups when supplies run low. The batteries will be large enough to supply the needs of an average house for 10 days if demands are conservative—and provide electricity for other houses, too.
If Ford sells more than 100,000 of its F-150 Lightnings in Colorado during the next decade, Gavan went on to say, that would create 7.5 megawatts of battery storage inside Colorado garages. “And we all know that cars and trucks are parked 95% of the time,” he added.
The Ford 150 —the model with gas-powered engines — was the top-selling model in metro Denver last year.
Viewing the future more expansively, Gavan wondered if other vehicle manufacturers will create enough options that Colorado residents will have 100 megawatts of battery storage sitting in Colorado driveways by 2030. That’s comparable with a small coal plant.
The implication of that question was this: If batteries in trucks, parked in garages and driveways can provide electricity for homes, maybe Xcel won’t have to invest so much in energy storage —and can pass along the savings to its customers.
Transmission is also part of this changing mosaic. A bill adopted by legislators this week will prod Xcel to join a regional transmission organization by 2030. Such organizations, called RTOs, are organized markets, where utilities share electricity as needed across a broader area than Colorado, conceivably to the sun-drenched states to the west or in the windy Great Plains.
After a decade of flat growth, demand for electricity from Xcel has begun to grow again. It will almost certainly grow in the future as Colorado stretches to electrify transportation. A quarter of bills passed in May and June by Colorado legislators also seek to dislodge fossil fuels used in buildings, which are responsible for 10% of the state’s greenhouse gas emissions.
As for peak demands for electricity delivered by Xcel Energy, it’s almost certain to grow as temperatures rise. The critical period is on summer evenings, from 5 to 9 p.m.
Warming is already clearly evident in Colorado. When Mike Nelson and other meteorologists talk about normal, they are referring to the 30-year average. Every decade, it is revised to reflect the most recent 30 years.
Denver’s average temperature was 1.1 degrees Fahrenheit higher for the new template of normals issued in May by the National Oceanic and Atmospheric Administration. Precipitation had trended downward. Both trends mostly prevailed across Colorado. As for the coming decade, the particulars can’t be predicted but rising temperatures can. It will get hotter yet.
Allen Best is a Colorado journalist with many years of experience following energy policy and politics. He publishes his own free e-journal at bigpivots.com. He wrote this analysis for Empowering Colorado.