Vanderbilt will begin work in October to convert its power plant to an all-natural gas-powered facility, a decision announced in April following approval by the Board of Trust.
Since 1988, the on-campus power plant, now personified by the smokestack and conglomeration of buildings that rise behind Rand and Buttrick Halls, has been powered by both coal and natural gas. In the coming months, renovations will begin to eliminate the university’s remaining coal-powered infrastructure and replace it with a system that runs completely on natural gas.
In pursuing this project, Vanderbilt will both eliminate its entire coal infrastructure and replace parts of the plant that are already using natural gas. The natural gas infrastructure is old enough that updates to the plant would soon be necessary to maintain efficiency. Instead of making these updates later, the university decided to completely modernize its system now.
The core part of the project involves installing two natural gas-fired boilers and one natural gas combustion turbine that will decrease the university’s peak demand, which is the highest amount of energy the plant uses at one given time. Decreasing peak demand is better for the environment, but also provides an economic benefit because the university is charged, in part, according to their peak demand.
While the renovations will largely be restricted to the plant’s current location, Assistant Vice Chancellor for Plant Operations Mark Petty explained that construction will also move near Vanderbilt Place for three to five weeks. A store of 100,000 gallons of emergency fuel will be placed underground, to be used only if both the Nashville grid fails and the university loses its access to its natural gas supply.
Petty expressed the university’s desire to complete this part of the renovations at a time when student traffic through campus is low, such as over a holiday break, in order to make construction as noninvasive as possible.
With the exception of that construction, the university expects the plant updates to remain largely isolated from students. Petty expressed confidence that students will not be affected on a day-to-day basis.
“As far as impact to the students…we have to do some site work, so there’s going to be a little noise from that, but as far as actually installing the turbines and the package boilers, they’d never know,” Petty said.
A long history
The Vanderbilt University Power Plant dates back to 1888, when the boiler in the original Mechanical Engineering Hall was used to heat and, after 1898, provide electricity for the entire campus. Because the university predates the Nashville electrical grid, the power plant was both important and revolutionary.
Starting in 1925, the coal-powered plant was moved to its current location, with updates made in 1962 and again in 1988, when natural gas was introduced as an alternate source of energy.
Why, though, with the Nashville electrical grid now in place, does Vanderbilt still need a power plant at all?
The answer is simple: Vanderbilt University Medical Center. It is essential that the Medical Center have a constant power supply. So, even though the Vanderbilt plant only provides the university with about 20 percent of its total energy, the university’s energy independence from the Nashville Electrical Grid provides assurance that the Medical Center, a Level 1 Trauma Center and home to experiments, samples and patients, will always be able to operate in case of an emergency.
Keeping the Vanderbilt plant running provides other benefits as well. Because the university can produce so much energy on campus, it saves more than 300,000 metric tons of carbon dioxide that would otherwise be released into the atmosphere while transporting energy to campus from other parts of Tennessee.
Now, the university looks to continue its power production in the most effective and efficient way possible.
At the suggestion of Chancellor Zeppos and Vanderbilt Chief Financial Officer Brett Sweet last fall, Vanderbilt Plant Operations began making plans for potential changes. After six months of research and planning, the proposal was presented to the Vanderbilt Board of Trust, who approved the project last April.
Plant Operations has since spent several of the 27 million dollars allocated for the project buying equipment in preparation for construction this fall.
Increasing the plant’s efficiency
Vanderbilt’s power plant uses a combined heat and fuel system, which means that as the plant produces electricity, it also produces steam. Usually, steam is a byproduct of plant operations and is released into the environment, often harming different ecosystems. At Vanderbilt, though, steam produced at the plant is actually recycled to continue to fuel the plant; heat is used to create more power.
Additionally, steam itself is used to fuel the medical center, providing roughly 90 percent of its heating and 40 percent of its cooling.
Vanderbilt’s renovations will make the power plant even more efficient than it is now. While the university will still produce roughly the same amount of steam it always has, the university will be able to produce more electricity year round. The current dual-pressure plant system allows half of the plant to be very effective in the summer, while half of the plant is most effective in the winter. Upcoming renovations will bring a conversion to a single-pressure system that makes the plant effective year-round and decreases the university’s need to buy electricity from Nashville to supplement electricity not being produced now.
The university’s move to a completely natural gas-powered system will have immediate aesthetic effects on both the student body and the university.
As the university’s coal infrastructure is removed, with it go the looming smokestack, coal hoppers, coal silo and baghouse, a three-story pollution control device that catches exhaust from burning coal. The additions to the plant will include a “shell,” said Andrea George, director of the Vanderbilt Office of Sustainability and Environmental Management, which will enclose the plant to give it the best aesthetics possible.
Additionally, conversion to natural gas will eliminate the need for the semitrailers that bring loads of coal to campus seven to eight times each day. Instead, gas is piped into campus through subterranean pipes that duck underground near the Student Recreation Center and end at the plant, allowing the university to generate the same power it always has with less noise pollution and a more appealing façade.
George said of the plant update’s effect on campus: “I think it’s very important that students understand that while this might not impact their everyday lives, it is an enormous improvement to our campus.
“Every dollar that we don’t spend on utilities is a dollar that can be used for our core mission. Long term, very important improvement is a huge step for the Chancellor and the Board of Trust to take, both for the economic improvement for the university but also the sustainability.”
Throughout its history, Vanderbilt has made a concerted effort to use only the cleanest coal possible—minimizing emissions—and to take necessary precautions to protect workers, students and the environment.
However, the detriments of burning coal are well known: releasing carbon dioxide into the atmosphere, creating emissions like nitrogen dioxide and sulfur dioxide that cause acid rain, dirty and inefficient methods of transportation and storage, potentially dangerous mining conditions and a constantly decreasing supply of coal. The transition to natural gas provides the university an opportunity to substantially decrease the plant’s negative environmental impacts.
Natural gas, however, has its own set of problems. The gas is highly flammable, making explosions a constant possibility. Fracking, a method of mining natural gas, is also controversial, as it involves extensive vertical and horizontal drilling into the earth as well as the use of potentially dangerous chemicals to drain the gas from the ground.
Despite these concerns associated with using natural gas, there is general support of the power plant’s update across the university.
Professor of Civil and Environmental Engineering and Chair of the University’s Environmental Affairs Committee James Clarke voiced his support for the project, citing the incredible decreases in air emissions the updated plant will bring.
“For a number of reasons, not the least of which is the aging of the plant and the money that would have to be spent to maintain it, it’s an opportunity…that is environmentally beneficial,” Clarke said.
He explained that, once the plant’s conversion is complete, hundreds of tons of pollutants like sulfur dioxide, nitrogen dioxide and carbon monoxide will be conserved and the existing emissions of mercury and hydrogen chloride will be completely eliminated.
Michael Diamond, president of Students Promoting Environmental Awareness and Responsibility (SPEAR), also affirmed his support, if more hesitantly.
“I’m mildly in support [of the use of natural gas] with proper regulations,” Diamond said.
George said in response to environmental criticism that, to date, there is no perfect energy source. Natural gas, she said, is Vanderbilt’s best option.
George confirmed that the university’s treatment of natural gas is carefully approached and extremely regulated. For example, Vanderbilt pipes in its natural gas supply, rather than storing it on campus. The plant’s design also includes safeguards, and the overall infrastructure is inspected multiple times each year.
George also added that the university’s experience with handling natural gas, after many years working with it in a lesser capacity at the plant, is definitely an asset.
Not out front, but in top third
Vanderbilt is not the first university to eliminate its use of coal. Institutions like Cornell University, Pennsylvania State University and Duke University all successfully converted to completely natural gas-powered energy sources in 2011.
Petty and George both commented on Vanderbilt’s place in environmental advancement.
“We’re in the most progressive third. There are still a lot of people out there who are burning a lot more coal. I mean, we’re a big coal consumer for middle Tennessee, but we’re nothing compared to other, large universities,” Petty said.
“That’s kind of the Vanderbilt way…” George added. “We’re very seldom out on the cutting edge. We kind of watch other universities and let them make the mistakes and learn the lessons, and then we kind of take what they’ve done and then jump on it, in the environmental field particularly. We’re not the first, but we’re in that top half or top third.”