Frequently Asked Questions

Q: What types of boilers are located in the utility plant?

A: As of July 1, 2011 there were four boilers in the utility plant. The boilers are described below.

•  Two stoker coal boilers that can co-fire natural gas at 20% of each boiler's total capacity

•  One fluidized bed coal boiler

•  One dual fuel natural gas/fuel oil boiler

The process of installing an additional natural gas boiler at Wade Utility Plant is underway. In 2012, after the new natural gas boiler is operational, one of the stoker coal boilers will be decommissioned.

Q: How are the buildings on campus heated?

A: The utility plant boilers generate steam which is distributed through a steam tunnel system at 125 PSIG and 15 PSIG. That steam is the sole heating source for 13.5 million gross square feet of campus buildings and is utilized in air handling units and for perimeter heat. Potable water is also heated with that steam. As the steam is used, it condenses and the condensate is returned to the utility plant. Over 90% of the steam that is distributed to campus is recycled back to the boilers.

Q: Do you make the electricity that is used on campus?

A: Purdue produces electricity as a result of the cogeneration process. In the cogeneration process, steam is used to heat buildings, drive chillers, and produce electricity. As the result of cogeneration, Purdue's environmental footprint is significantly reduced.

Over the course of the year, we typically generate 30-50% of the electricity required to meet campus needs. During the last fiscal year, we self-generated over 40% of the electricity required to supply the 16.5 million gross square feet of campus buildings connected to our electric grid.

Q: How are the buildings on campus cooled?

A: Purdue generates chilled water from two locations on campus and distributes that chilled water to over 11.7 million gross square feet of campus buildings. The approximately 45 degree Fahrenheit chilled water is circulated through air handling unit coils at each building and is then returned to the chiller locations to be chilled again for redistribution.

Q: How much coal do you burn each year?

A: During the last fiscal year, Purdue burned approximately 178,000 tons of Indiana coal. The amount of coal burned will be reduced after one of the stoker coal boilers is decommissioned in 2012.