DU Uses Cogeneration to Meet Power Goals

PITTSBURGH — An energy center at Duquesne University (DU) in Pittsburgh is now responsible for providing the entire campus with all necessary electricity, heating and cooling.

Within this center, a powerful, gas-fired turbine generates more than three-quarters of the university’s power. In addition, its excess heat runs boilers, which are then used to warm campus buildings in the winter, and powers chillers that are used for air conditioning in the summer.

When the energy center initially went online in 1997, this use of normally wasted heat energy, otherwise known as cogeneration, was more than enough to handle the campus’ power requirements. However, building expansions on both sides of Forbes Avenue have made additional sources mandatory.

The planned expansion, which will include a boiler replacement, is the latest in a series of improvements since 1997. Several years ago, the center added huge chiller tanks powered by the turbine to cool buildings more efficiently than by individual units. The center also added large tanks to hold water for the boilers in case a main break cuts off service.

Another prior addition established pipes, which run through tunnels beneath the 50-acre campus feeding hot air or cold water into buildings. The pipes run through the garage to cooling towers that the university recently moved from atop the energy center, where a green roof is planned.

In response to the need for further expansion, the state’s Alternative and Clean Energy program awarded the university a $2 million grant to support the roughly $11.5 million expansion project. This expansion would nearly triple the capacity of the energy center’s boilers while also decreasing its natural gas consumption.

Furthermore, state agencies, including the Public Utility Commission, have also encouraged such cogeneration projects.

Yet, Duquesne’s purpose in reducing fuel consumption largely rests on its own environmental stewardship goals. Examples of these goals, which the university has met in the past, include a sustainable MBA program, new LEED certified buildings and the increased use of wind-powered electricity.

“With this center, we can practice what we preach,” said Rod Dobish, executive director of facilities management for Duquesne, during a recent tour of the plant.

Dobish and Mark Johnson, energy center manager, hope to begin this expansion in summer 2016. However, efficiency work will not end with the boiler installation. Duquesne also plans to install electric meters which can provide detailed data on each building’s hourly use and help identify areas to cut back at a further time.