There will be the usual road closures near campus next month, but not for the usual type of construction.

Three new boilers, each weighing 160,000 pounds and resembling an industrial trailer home, will be arriving in Ames to be installed in the ISU power plant.  

The boilers will be joining five remaining boilers in the power plant. Two of the old boilers still run on coal and three have been converted to burn natural gas. Natural gas burns more cleanly than coal, resulting in fewer emissions.

The three new natural gas burning boilers will replace two coal-burning boilers that were removed last spring due to age, pollution and comparative inefficiency. The process of removing those boilers cost Iowa State $2 million. The housing and installation of the new boilers will cost another $42 million.

“We’re switching the consumption from where we are now, burning pretty much all coal, to burning at least half our fuel as natural gas moving forward,” said Warren Madden, senior vice president for business and finance. “Environmentally, we want to be burning alternative fuels when it makes sense. The balance you have is meeting the environmental standards and keeping costs reasonable.”

Madden said Iowa State has been keeping costs at a reasonable level the past few years. The power plant has not raised its rates and Iowa State has not raised tuition for the past three years.

The power plant has functioned as a utility for decades, charging buildings and residence halls on campus for the energy they consume heating and cooling the buildings.

In the winter, the steam directly provides heat for the buildings through a system of underground steam tunnels and in the summer, that steam powers a system that pumps chilled water throughout campus to provide air conditioning.

The boilers can also be used to power electric generators. Electricity for campus is often purchased from the City of Ames power plant for economic reasons.

The daily choice is based on varying costs of producing and buying the electricity, which are both related to the total consumption of the community. Buying the electricity often saves money because the ISU power plant, as a utility, can purchase the electricity at a lower price than individual consumers.

Lindsey Wanderscheid, manager of the construction project, said the new boilers will reduce the power plant’s emissions of chemicals, like sulfur dioxide, by as much as 80 percent.

A new sorbent system will accompany the boilers, using hydrated lime to neutralize hydrochloric acid and will reduce those emissions by as much as 85 percent.

Wanderscheid said the first new boiler is expected to be running by late summer and all three are are scheduled to be operational by the end of the year.

Although the new boilers continue to run on fossil fuels, Madden said there has been research on campus to find more sustainable fuel sources.

“The [older] boilers can burn certain materials. We’ve tried to burn old tires at one point, we’ve burned biomass materials — corn and those types of products — we’ve burned some construction debris materials … the problem with some of those is getting a sufficient quantity that is consistent enough to meet the environmental standards,” Madden said.

“The goal is to have multiple fuel sources, so as both prices and supply change over time, the university has some flexibility [in its fuel choices].”