Princeton University’s microgrid is green–but not in ways that are obvious.
Yes, the university has solar–a field of 16,000 solar panels that produce 4.5 MW or 6 percent of the university’s power, says Ted Borer, energy plant manager. Click on the player above to learn more about the humble ways the microgrid is green.
Princeton’s cogeneration plants produce half the electricity needed by the university. They’re dispatched on an economic basis, which saves money for the university.
“When utility prices are high, we generate, and when utility prices are low, we run a minimum load and buy it from the utility. This is economic and reduces our carbon footprint,” he says in the interview.
The cogeneration–which is 80 percent efficient–is the first step in the university’s effort to be clean and green. Steam is used to heat buildings in the winter and run chillers in the summer.
“This is combustion-based and super efficient,” says Borer, who is also co-chair of the Microgrid Resources Coalition.
The university takes advantage of building controls, monitoring and controlling over 100,000 different pressures, temperatures and humidities around campus.
In addition, the university continues to retrofit its plant to reduce the energy it requires, he says in this interview. “We change motors and pumps and we add variable frequency drives, which drives down the electricity required for the same pumping energy delivered. We recover a lot of heat that goes up the stack and re-use it.”
Princeton is a net purchaser of power, but if the grid is shut down, the university can de-couple and run as an island. “We did this during Hurricane Sandy,” says Borer. “We kept the lights on while most of New Jersey was dark. We kept the lights and steam on, and first responders came here to get out of the cold.”
Listen to our interview with Borer by clicking on the link above.
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