Brodie Griffin likes to describe the heart of his work as a 16-story, 2,400-degree "fire tornado."
At all hours of the day and night, that fire tornado whips around a giant metal box in the center of the Platte River Power Authority's (PRPA) Rawhide Energy Station, a coal-fired power plant rising out of the plains in Wellington, Colorado.
Griffin is the site’s technical services manager.
“This is the boiler, and right on the other side of these walls, that's where that 2,400-degree flame is burning,” he said, shouting over the roar of machinery during a tour of the facility on a recent afternoon. “The walls of that furnace are made up of steel tubes that are welded together. There's literally miles and miles of tubing.”
The heat turns water inside of those tubes into high pressure steam, which is funneled through giant pipes down to the third floor turbine room.
“There's actually three (turbines),” Griffin explained. “They're all bolted together, one right after another.”
They form a rotating shaft that turns a generator to produce 280 Megawatts - electricity that powers homes and businesses in all of Estes Park, Loveland, Longmont and Fort Collins.
And the scorching fire tornado behind the entire chain reaction is fueled by massive amounts of coal.
“At full load, we burn about 300,000 pounds (of coal) per hour,” Griffin said. The coal is shipped in by the trainload twice a week from a mine 200 miles away in Wyoming. The scale of activity required to keep the lights on in just four Northern Colorado communities is humbling.
But things are changing.
PRPA needs to cut its carbon footprint to comply with current state law, which mandates an 80% carbon reduction by 2030 from the power plant sector. Economic pressures also point in that direction: energy from wind and solar is now cheaper than fossil fuel-based energy, leaving the utility with no choice but to embrace more modern and affordable sources of power. All of that leads to one over-determined outcome: The power authority's vast coal-fired operation will be shutting down for good in about six years.
“The amount of megawatt hours that come from this resource will slowly tail off as we move towards 2030,” Griffin said. “And then at some point, we'll actually end and we'll shut the unit off.”
The question of exactly how PRPA will replace the massive coal unit after its demise remains a source of concern and contention for both the utility and the communities it serves.
Much of PRPA’s energy future will be in the form of wind and solar. In 2018, facing pressure from the four communities it serves—all of which have climate action plans that include steep carbon footprint reductions, the utility adopted a goal to get energy from 100% carbon-free sources by 2030.
And yet, in October the utility board approved a plan to invest some $250 million in new turbines that run on natural gas - a decidedly not carbon-free fossil fuel.
Community pushes back against natural gas
Natural gas is a fossil fuel energy source primarily comprised of methane, a powerful climate-warming greenhouse gas. It burns cleaner than coal, but it’s still not clean. Experts, like the International Energy Agency, say we still need to use a lot less of it in the coming years to avoid catastrophic global warming.
So, when the utility went public with their plans to go ahead with gas-burning turbines, Fort Collins resident and PRPA ratepayer Sue McFaddin was baffled. She is deeply concerned about global warming and had been counting on the utility to make good on their climate commitments.
“The plan was that, over the decade, we were gonna get to 100% renewable energy by the time the coal plant closed in 2030,” McFaddin said. “I was really shocked that they were going to build a gas-fired power plant. I know there's far better solutions out there.”
McFaddin calls the gas turbine plan an expensive waste of time and money that could be better spent meeting the renewable energy goal.
“I think they're actually ignoring the goal,” she said.
Aspirations versus plans
According to Platte River Power Authority, investing in more natural gas burning equipment is essential to reducing their overall carbon footprint while continuing to provide reliable and affordable power to customers.
Javier Camacho, the communications director at PRPA, said the 100% carbon-free by 2030 goal is aspirational—but not actually achievable. He explained that the goal was always to "proactively work towards 100% by 2030," acknowledging that working toward a specific number is not the same as hitting it.
"We understood that at the time ...that major evolutions, maturity and technology and other caveats...needed to happen in order to make this successful transition," he said.
Those technological leaps forward, he said, are not under PRPA's control. They haven't yet been realized, and may not be before the end of the decade.
“It would be irresponsible, I think, of any utility to say that they are going to make a full transition by a certain date, understanding that major technologies have not quite matured yet,” Camacho said.
But he added that the utility does have a clear path planned out to produce 88% carbon-free energy by that year – a plan that relies on introducing some new gas-fired power resources.
Growing need for grid reliability
Brodie Griffin said the new gas-fired technology is a reliability resource.
“We see it as a way to maintain stability within the electric grid.”
Masood Ahmad, PRPA’s resource planning manager, said grid reliability is part of the utility’s essential function, and that issue will grow more urgent as greater parts of the economy go electric.
State and national climate action plans call for a major shift to electrify the transportation and building sectors. And as more areas of life – from cars to home heating - come to depend on the grid, the impact of a power outage will become increasingly significant.
At the same time, that shift also means that as the grid becomes greener in the coming years, communities will be placing much greater demands on it.
“Our load is going to continue to grow,” Ahmad said. “2030 is a milestone for us. But after that, we see more electric cars coming. More home heating is going to continue to grow the load.”
The role of gas in the energy transition
Jaquelin Cochran, director of the Grid Planning and Analysis Center at the National Renewable Energy Laboratory, said with all the coming shifts in the energy sector, utilities like Platte River worry about keeping up with all that growing demand.
”What a utility never wants to do is be out of power,” she said, “Especially if they want to encourage the residents to electrify.”
According to Cochran, solar and wind are the major players in the transition to carbon-free energy. Those renewable sources are now robust and cheap enough to provide for the vast majority of our base energy loads—our normal, daily power needs.
But base load coverage isn’t sufficient. On the one hand, wind and solar are intermittent – when sun and wind aren’t available, energy generation grinds to a halt. And on the other hand, they can’t be quickly ramped up as needed when energy demands spike past base demand – like on particularly hot summer days when a lot of people turn up air conditioning all at once.
Or as Cochran explained it: “You can get a lot of renewable energy, but it's not necessarily at the very time you want it.”
Better technologies that can shore up the reliability of a carbon-free grid are on the horizon. Long duration battery storage, for instance, can keep solar-generated power bottled up for that proverbial rainy day. Distributed energy resource technology decentralizes energy generation and can boost grid power from sources like individual rooftop solar panels. Demand response technology can nudge customer behaviors to smooth out the demand curve and avoid big load spikes.
But most of those technologies aren’t ready for utility-scale prime time just yet, either because they still cost too much, or the supply chain can’t yet deliver them at scale. The problem, Cochran said, is that they probably won’t come into their own as practical, economical options until the middle of the next decade – in other words, not until after PRPA’s deadline for shutting down the Rawhide coal plant.
The gas-fired turbines, she said, are a way for PRPA to fill that gap.
“If you're a small utility and you know you're going to have this need, you don't want to wait because you're at risk of not meeting the demand for electricity,” Cochran said.
The Big Kahuna
Fort Collins Mayor Jeni Arndt, who sits on the PRPA board of directors, approved the utility's gas turbine plan in October, but said that doesn't mean she's turned her back on the carbon-free future.
“It feels uncomfortable to invest in something new that does use fossil fuels,” she said. “I just don't want it to be misunderstood that this is somehow a backing off on the commitment to clean energy. I think it is the key to the transition.”
She’s accepted the lower emissions from the gas-fired technology in exchange for eliminating a bigger source of pollution: the coal-fired power plant.
“That's the big kahuna,” Arndt said.
But environmentalists, like Sierra Club regional press secretary Noah Rott, say we urgently need to end our reliance on fossil fuels, not devise ever more uses for them.
“We're always going to be concerned about any new gas,” Rott said. “Experts say we can't build out new gas, and we need to stop fracking. We need to stop as soon as possible.”
He said now is the time to think big and embrace innovation.
“You set this goal, and now at this moment where it's really critical for us not to adopt false solutions for meeting those goals, it feels like they might be adopting those false solutions,” he said.
