As temperatures in northern Colorado hovered near zero on Sunday, an electric cooperative serving Grand and Jackson counties sent an urgent message to its customers and local media: Because “regional wind turbines iced up and are unable to generate electricity,” Mountain Parks Electric said in an alert just after noon on Feb. 14, customers were being asked to “conserve energy immediately.”
No power outages occurred, and the utility’s conservation request was lifted within hours. But like other stresses on electric grids across the country amid frigid temperatures caused by a polar vortex this week, the incident was seized upon by defenders of the fossil-fuel industry, including the president of the Colorado Oil and Gas Association, who said that it illustrated “the limitations of today’s renewables.”
In reality, however, the electricity supply issues that led to Sunday’s conservation request were much more complex, according to internal and external communications from a regional power supplier that were obtained by Newsline.
In addition to causing problems for wind and solar generation, weather conditions also impacted the supply of natural gas, while a problem at a Wyoming coal plant limited its output. Reliability concerns from administrators overseeing a regional balancing market added a further wrinkle.
The causes of the power supply issues were spelled out in greater detail in several emails sent by Tri-State Generation and Transmission Association CEO Duane Highley following the conservation request, and confirmed by Tri-State representatives. Based in Westminster, Tri-State is the wholesale electricity provider for 45 member co-ops in Colorado, Wyoming, New Mexico and Nebraska.
”The story here is that the lights stayed on during widespread and sustained record cold weather,” a Tri-State spokesperson wrote in an email. “While this weather event itself was historic, its impact on our system was not unlike weather events we have seen in previous years.”
Challenges to both renewables and fossil fuels
As supply concerns mounted on the morning of Feb. 14, Tri-State contacted 10 of its member co-ops in Colorado and Wyoming with a request to conserve power.
Mountain Parks Electric, which serves a 4,000-square mile area in rural north-central Colorado, promptly issued an alert asking its customers to turn down their thermostats by a few degrees and forgo washing dishes and clothes — and blaming frozen wind turbines.
“In the past hour, MPE received notification from its power supplier that regional wind turbines iced up and are unable to generate electricity,” the message said. “This has created the potential for an interruption of electric service for MPE and its consumers.”
“That was the message that was relayed to us from our power supplier,” Rob Taylor, MPE’s communications manager, told Newsline. “So whether or not that was the full story, I can’t answer that.”
In an email to Tri-State’s board several hours later, a copy of which was obtained by Newsline, Highley briefly detailed the causes of the conservation request, which were significantly broader and more complex than iced-up wind turbines.
“Weather conditions have impacted natural gas supply and cost, affecting our ability to run gas units, and limited wind and solar production,” Highley wrote. “Issues at several thermal plants affected output. Other utilities are also affected by these conditions, which limited the ability to buy power, or receive power under agreements.”
“Thermal” power plants refer to those fueled by heat sources like coal and natural gas. Lee Boughey, Tri-State’s vice president of communications, confirmed to Newsline that a coal-fired generating unit at Laramie River Station experienced a problem that contributed to the Feb. 14 supply strains.
“Sustained and extremely cold weather impacts the electric system with higher energy demand, increased pressure on natural gas infrastructure, and challenges to operating both thermal and renewable energy generation,” Tri-State said in a statement. “Severe weather can impact generating units of all types.”
Grid resiliency in the spotlight
The historic cold snap caused by the polar vortex — itself a product, many scientists suspect, of climate change in the Arctic — has led to stresses on electric grids across much of the central United States.
Platte River Power Authority, an electricity wholesaler serving four local utilities along the northern Front Range, including Fort Collins, issued a similar conservation request on Feb. 14 due to a combination of wind outages and a curtailment of natural gas caused by heating-sector demand, according to the Coloradoan.
Most dramatically, frigid temperatures caused days of rolling blackouts in Texas that have affected millions, thanks to power supply deficiencies caused primarily by shortages of natural gas.
Many advocates for the fossil-fuel industry, however, have pointed to the reduced performance of wind and solar generation in the winter months to oppose renewable-energy proposals that they say are unrealistic. Dan Haley, the president of the Colorado Oil and Gas Association, shared local news coverage of Mountain Parks Electric’s Feb. 14 alert on Twitter the following morning, commenting, “Political agendas won’t heat our homes but a realistic, risk-based energy policy, which includes natural gas, will.”
As Colorado state lawmakers resumed the 2021 legislative session on Feb. 16, House Minority Leader Hugh McKean, a Republican from Loveland, told his colleagues on the House floor that Platte River’s “disturbing” conservation request was proof that Colorado’s energy future must include fossil fuels.
“All of the lofty goals of having 100% renewable energy were not sufficient to both provide the electricity we all demand as well as heat for our homes,” McKean said in a speech opening the legislature’s regular session. “The 21st century should not hallmark a return to the candles and wood stoves of the 19th.”
Nationally, the electricity crisis in Texas has been seized upon by many prominent conservatives — including Colorado Rep. Lauren Boebert, who has shared misinformation blaming “frozen windmills” and other debunked claims on her Twitter account — to cast doubt on the viability of wind power altogether.
“I think that’s a really simplistic understanding of the power system,” Erin Overturf, deputy director of the clean energy program at Boulder-based Western Resource Advocates, told Newsline in an interview. “We’re solving this puzzle — part of it is reliable service, part of it is cost, part of it is emissions. If you’re not able to solve for all three of those, it’s not a workable solution.”
Renewable energy experts, utilities and policymakers have spent decades charting a course towards a 100% renewable electric grid in order to eliminate the greenhouse gases that cause climate change. Despite the rhetoric of many opponents of clean-energy policies, the intermittency and seasonal variability of wind and solar generation haven’t eluded them.
“There’s no one who is actually knowledgeable about the electricity system who doesn’t already know that the wind doesn’t blow all the time and the sun doesn’t shine all the time,” Overturf said. “Everybody knows that. That’s why we’re figuring out new technologies and new solutions that are going to overcome those characteristics of intermittent renewable resources.”
Those solutions are likely to include long-term, utility-scale batteries that can store excess wind and solar power to be used later, and a nationally integrated electric grid that can shift power between regions as needed.
“I don’t know exactly what the 100% clean grid of 2050 is going to look like,” Overturf said. “It’s impossible to foresee what specific technologies are going to be the right choice for us to power our economy in 2050. What we do know is that technology is changing, and the economics are changing, incredibly quickly.”