Iowa State University this year plans to install three, 80-ton natural gas boilers that will replace coal-burning models in a $42 million project that will cut the power plant’s coal use by one-third.

The boilers were scheduled to arrive at ISU’s power plant at 11 a.m., 2 p.m., and 5 p.m. today by oversize load along Pammel Drive. Manufactured in Lincoln, Neb., the units are 43 feet long, 16 feet tall and 13 feet wide.

When the new boilers are in and old boilers have been retired, ISU will have two coal-burning boilers left. During most of the year, the university will run two gas boilers and one coal boiler.

The new boilers will lower operating costs in addition to reducing emissions significantly. It also will reduce the amount of coal ash, a byproduct of coal-burning that caused ISU controversy over disposal plans over the years.

The new boilers, used to produce steam, electricity and cooling water for campus, should be operating by the end of the year. They were financed with bonds backed by campus utility rates.