Power plant to burn through final shipments of coal

Jack McCllelan

The eastern face of the power plant houses much of the infrastructure built to move and process coal, including silos, conveyor belts, elevators and more.

Iowa State’s power plant is approaching the end of an era as it burns through the remains of its final shipments of coal.

Since 2016 Iowa State has been in the process of updating its boilers to run on natural gas. Currently, the power plant consists of five boilers, only one of which runs on coal.

During the winter, the power plant relies on all five boilers running intermittently to produce the energy required to keep the campus running. As winter draws to a close, the plant will take the coal-fired boiler offline to begin transitioning it to run on natural gas.

Director of Facilities Planning and Management Mark Kruse said ending the plant’s coal consumption will allow for savings in handling coal. He said over the past several months, power plant staff have been working hard to keep the coal systems running.

“There will be many jumps and shouts from our maintenance staff,” Kruse said.

Unlike a natural gas boiler, the coal-fired boiler relies on a number of systems to crush the coal into acceptable sizes, transport it, mix it with limestone (to reduce sulfur dioxide emissions) and elevate it into a silo before being fed into the boiler.

Kruse said in the last week of February, the power plant had to take the boiler out of service for three days while staff jackhammered a buildup of coal and limestone slag out of the inlets of the boiler.

“That’s what we’ve been struggling with, continuing to try to keep the boiler operable until we deplete the last of our coal stack here,” Kruse said.

The power plant has been decreasing the coal maintenance staff through attrition over the past few years. Kruse said with only four staff members remaining, the coal maintenance team has had its hands full with keeping the boiler operating.

Kruse said by updating the final coal-fired boiler to run on natural gas, the university will have met its goal of reducing emissions by 50% from a baseline in 2012.

He said transitioning the boilers makes up 35% of the emission reduction while the rest is covered by purchasing renewable energy credits.

After the transition, Kruse said the boilers would likely have 20-25 years of life left in them, though he added that the university is continuing to look into alternatives for powering campus.

“It’s not the end-all be-all by any means,” Kruse said, “but [with] our natural gas costs, we can purchase gas about $2 million a year less than what we can for the same energy content of coal, and then we can also reduce a lot of our maintenance and repair work.”

Kruse said the university is currently benchmarking various options and how they align with the university’s infrastructure and future energy needs. He said they are assessing these options considering the savings they could produce and the cost of implementing the alternative energy sources.

Kruse said that while the university has started some interactions with local utility providers in regard to renewable energy, they would likely double the annual utility cost. He said in considering infrastructure-intensive systems like geothermal energy, the university would be looking at billions of dollars.

“So really, what we’re trying to ascertain is, ‘How can we position ourselves and continue to move forward with reducing emissions without breaking the bank or impacting tuition costs?’ and just being good stewards of [students’] tuition payments and things like that as well,” Kruse said.

Jackalyn Sorensen, a junior in journalism and mass communications and a member of the Climate Reality Campus Corps, said it is about time the university ended its coal consumption.

“I think we’re a really huge campus, and if we’re going to try to emphasize the innovation on campus, I think it’s about time to start making that sustainable as well,” Sorensen said.

Sorensen said because Iowa already generates most of its power through renewable sources, Iowa State should look to powering campus with more sustainable options.

“It’s impossible to totally remove our carbon footprint, but it’s not going to be much of a help if it’s going to be something that’s still emitting lots of CO2 into the atmosphere,” Sorensen said.

Sorensen said while renewable energy is more costly and takes a lot of manpower, the positive effects on the environment make the investments worthwhile.

“I think it’s a step in the right direction, but I think there’s more that we could do,” Sorensen said.

While this important milestone marks the end of Iowa State’s 150-year dependence on coal, some power plant staff members say it is bittersweet to see the plant’s final coal-fired boiler begin its transition to running on natural gas.

Plant Services Supervisor Larry Battazzi said he did like to see a variety in the fuels the power plant operated on. He said the plant was able to save a lot of money by operating on coal when it was able to.

Utilities Plant Operator Jerry Garcia said the power plant looked nothing like it does now when he started in 1982.

“The thing about running coal was that there’s an art to it because the coal that you were burning [had] different BTUs [British Thermal Units] depending on where it came from,” Garcia said, “But with the gas, it’s got a certain BTU; you push the on button and off it goes; up arrow means to increase, down arrow means decrease.”

Garcia said starting the boiler back in the day was a much different ordeal than it currently is. He said a staff member would crawl inside the boiler with diesel fuel and spread it around the coal, then another would light a roll of toilet paper, also saturated in diesel, and toss it into the boiler to get the fire started.

“It was a lot of fun, actually,” Garcia said.