By Andy Zou
On Feb. 25, Assistant Director of Facilities Marc Donovan gave a presentation at the last U-Sustain meeting of this term on the college’s proposals to build a new cogeneration plant, as well as the college’s path toward achieving carbon neutrality. The focus of the talk was to raise awareness of anticipated energy challenges that the college faces, and why cogeneration was ultimately chosen as the solution in order to meet energy demands.Union currently pumps green energy into the system, and purchases green power from National Grid. Portions of the power Union purchases from National Grid were produced by coal-fired, and renewable or non-renewable power plants.
Donovan emphasized that he sought to find a solution that was sustainable, defined as being environmentally, socially, and fiscally responsible. The alternative to building a cogeneration plant was to build a traditional generator while purchasing more power from National Grid. While this solution would be cheaper than a cogeneration plant, Donovan believed that continuing to support a utility monopoly was antithetical to the college’s sustainability mission. The cogeneration plant was therefore the best solution, as the plant would allow the college to produce much of its own energy on campus.
The cogeneration plant is a combined heat and power generator fueled by natural gas. It will consist of a turbine, heat recovery steam generator and an absorption chiller. Much of the waste heat that would be normally lost to the environment in a traditional generator will be reused internally under the cogeneration process to produce steam that would meet much of the college’s heating and cooling needs. By using a single source to fuel one combined process, the cogeneration plant will be about 80 percent efficient.
Nonetheless, not all students were convinced about the cogeneration plant. Students raised questions on whether continued reliance on natural gas for the next quarter-century would be the best course forward. In response, Donovan said students should look at cogeneration’s use of natural gas in another way — the fact that cogeneration would result in a reduction of 55 percent, or equivalent 75,000 decatherms, of natural gas burning, as compared to building a traditional power substation.
Donovan said that students should also look at cogeneration in light of the lack of alternative renewable sources able to provide stable power quickly for the college’s growing energy needs. He said the cogeneration plant is needed because the college has already approached the power supply threshold level that National Grid allots.
The need for the cogeneration plant comes at a time where the college’s energy demand has risen dramatically with the construction of new buildings over the past few years. Donovan cited the renovation of the Visual Arts Building, expected to commence this summer, the new residence halls under construction and the ongoing dehumidification needs of an expanding college as reasons that energy demand is expected to continue to increase. The cogeneration plant will reduce future reliance on aging infrastructure by providing 75 percent of the power, 87 percent of the cooling, and 97 percent of the heating needs of the college. The remaining energy needs will continue to be obtained through National Grid and the college’s existing boiler plants.
The cogeneration plant carries a price tag of around $13 million dollars, with an expected return on investment in eight years. The cogeneration plant is critical to the college’s eventual mission of achieving carbon neutrality.
Union’s Climate Action Plan, drafted in 2008, envisions that the college will achieve carbon neutrality by 2060 and cut net carbon emissions by 15 percent in 2015 from the emission baseline levels of 2008. The college is actually 17 percent of the way toward this goal. A one-time jump to 52 percent off net carbon footprint is expected the year that cogeneration comes online. The cogeneration plant will thus allow the college to achieve carbon neutrality by 2037, shaving 23 years off the total carbon footprint.
Donovan has already been planning ahead for the next few years, when cogeneration comes online, taking steps such as predicting energy load, modifying campus systems and energy-intensive appliances to adapt to cogeneration and to plan and meet campus programming needs for cogeneration. Donovan has been looking to other colleges for green initiatives and sees hope for the future. Although Union’s hip-styled roofs make capturing solar impractical when mounted on top of buildings, a solar farm in the next decade or so could help accelerate the goal of achieving carbon neutrality by another seven years. Cogeneration and solar combined would allow the college to reach carbon neutrality around 2030.
Donovan explained that there has been a lot of knowledge growth since the original plan was drafted, and he wants to build on the momentum that allowed the college to be ahead in its sustainability and carbon neutrality goals, but he is still deciding whether the college should take a steeper path, or a more conservative path towards carbon neutrality after cogeneration comes online.