Power was out on campus early Tuesday morning and returned as of 7:15 a.m. Tuesday, affecting stop lights and buildings on the north, east and south sides of campus, along with steam and cooling levels at the university.

The campus lost the connection to the City of Ames due to failure in a transformer, Utility Services Director Jeff Whit said, which contributed to the outage.

Iowa State has the capability to generate all the electricity for the campus with its own generators or can choose to purchase electricity, according to a utility consumption webpage for the university. 

That website says Iowa State purchases electricity a day ahead on the Midwest Independent System Operator (MISO) open market, which manages and operates the electrical grid in the upper Midwest. Iowa State schedules power a day in advance for each hour of the following day, according to the webpage. Operators at the Iowa State power plant work closely with operators at the City of Ames power plant to coordinate power purchases from MISO whenever it is more economical.

According to Real Time Energy Consumption charts on that webpage, gas to the boilers dipped into the negatives during the outage while purchased power remained unaffected.

Iowa State also purchases electricity from a wind farm located approximately 15 miles northeast of Ames. The quantity of the power available from the wind farm varies continuously with the wind speed.

Iowa State Police sent out a message via Twitter at 6:58 a.m. Tuesday morning letting the community know that stop signs would be placed at non-working stop lights.

Facilities, Planning and Management is also working on returning air conditioning to the buildings affected. All steam and cooling was affected, and due to the heat, will take awhile to return to campus. Temperatures are likely to go over 100 degrees fahrenheit today with the heat index.

“It’s going to be humid and warm from the buildings,” Whit said. “People need to take normal precautions for the heat.”

According to a  utility website, the ISU Power Plant has several systems that work together to cool the campus. Whit said the steam, produced by one system for the others, was affected by the outage.

The steam is used to generate electricity, heat the campus and to produce chilled water for cooling the campus buildings.

Cooling has been steadily returning since 8:30 a.m., according to data collected in real time at the plant. Yesterday, cooling peaked at 3586.933 tons.

For perspective, a typical home air conditioner is rate at 2 to 3 tons of cooling, according to the utility webpage. tons. As of 9:30 a.m., the university was at 894.334 tons.