By SASHA HART
In 2007, Colorado College students asked then-president Dick Celeste to commit to making CC a carbon neutral campus, and in 2009, CC promised to become carbon neutral by 2020. The Office of Sustainability, following through with this promise, proposed in the very early stages of planning for the new library to be carbon neutral.
With the arrival of the new school year, much of the buzz around campus has been about the new library. However, not many people seem to know what it means that the library is now a net zero building. Unlike a Leadership in Energy and Environmental Design (LEED) certification, which Dean of Sustainability Ian Johnson described as “a checklist of components,” designing a net zero building “guarantees performance.” The general premise of a net zero building is that it will create as much or more energy than it uses and will remove as much carbon as it consumes. However, the systems that make this happen are more intricate.
Because the building was intended to be carbon neutral from the very early stages, the cost of building remained on budget at $45 million. CC enlisted the help of specialty engineers and contractors with knowledge of net zero systems to complete the library renovation.
But what are some of the features of carbon neutrality? Starting with the the most noticeable, the library has increased insulation, LED lighting throughout, and occupancy sensors for lighting. The occupancy sensors are also used to determine which areas and rooms in the library need air conditioning or heating and which don’t. Still, there is much more to the system than meets the eye.
Under the quad, there are 80 geothermal wells drilled over 400 feet deep, where the earth maintains a consistent temperature of about 52 degrees Fahrenheit. These wells circulate water that works to heat and cool the library. The wells are also capable of storing heat generated during the warmer months for later use. Inside the building the temperature is regulated and efficiency is maximized using a system called the Variable Refrigerant Flow system. This system draws air from one part of the library and distributes it to another to regulate the temperature in each area. For instance, if an office is too cold, but a study area is too warm, the Variable Refrigerant Flow system can move air from the study area to equalize the temperatures.
For its power needs, the building draws upon a natural gas generator connected to a combined heating and power system which, if it produces more heat than is needed for the library, can send heat to the rest of campus. However, burning natural gas produces carbon emissions. To offset this, the library has on and off campus solar arrays that supply some of the library’s power needs and feed clean energy back into the municipal grid, which largely relies upon coal.
As a new building, there are likely still some tweaks that need to be made over the coming year before the building will be operating as effectively as possible. As Ian Johnson explained, “The building is not necessarily operating at its peak efficiency right now.” Net zero efficiency is measured over the course of a year, which means that on any given day the building may not be functioning as net zero, but over the course of the year, it should balance out. All the systems in the building have monitors that provide data about their carbon usage, energy production, and net offsets, so that tweaks and calculations can be made to achieve complete carbon neutrality.
As for the future of net zero construction at CC and the status of the college’s commitment to becoming carbon neutral by 2020, the college is certainly not planning on rebuilding every building on campus to meet net zero standards in the next three years. However, the college is still very focused on promoting sustainability in its plans. Jill Tiefenthaler noted that “our [college’s] strategic plan makes it clear that our goal is for the college to be recognized as a model of environmental stewardship and innovation by advancing both the study of practice of sustainability.”
Moving forward, the Office of Sustainability is considering the possibility of purchasing renewable energy credits or carbon offsets. Until the college can eventually own their own renewable energy or achieve carbon neutrality through other methods, this will help achieve the goal proposed by students 10 years ago.