Power Hungry

On a golden day in October in New Haven, Connecticut, in a tall, old red-brick building on Yale’s immaculate campus, natural gas combusts at 1,200 degrees.

“Maybe hotter,” says Tom Starr, the manager of Yale’s Central Power Plant. Starr leads me up a few metal steps and opens a hand-sized hatch on the side of a huge, green, insulated-steel box to reveal a little window. Inside, the space explodes with outlandish purple and yellow flames.

We’re looking at the burner that provides fuel to the big green box, called a boiler. Natural gas burns to make heat in the burner. The heat turns water into steam in the boiler. And steam is everything. Steam runs all over campus to meet space heating and hot water needs. It powers the turbines that run steam-driven chillers to make chilled water for air conditioning. It drives the pumps that push chilled water in huge blue pipes from the power plant to every corner of campus. It keeps us warm, it keeps us cool, it keeps our showers hot and our dishes clean and our dining halls open, and it protects priceless research by maintaining the precise climate conditions required in labs on Science Hill.

Starr explains all of this as we walk through the plant. He speaks with the conversational manner of a practiced tour guide, casually slipping in technical terms just a beat too fast for me, but with the volume of a bullhorn, competing with the noise of the plant. It is a hissing, buzzing, roaring, put-on-your-hard-hat kind of noise, slightly different in each part of this maze of metal and concrete. My own hard hat keeps slipping down my forehead and clanking against my safety goggles. It’s pitiful enough that Starr interrupts his well-honed speech to help me adjust the hard hat. My eyes and ears must be at their best to take in what so much of the Yale community remains blind to.

After a few years of working on the advocacy side of Yale’s commitment to sustainability by trying, mostly in vain, to pound conservation into student behavior—most recently as the head of the energy team in the Yale Student Taskforce for Environmental Partnership (STEP)—I have come in search of the commitment on the ground. What is it, exactly, that we pollution-haters are trying to replace? Images of the University’s bright future hide what could be the strongest potential motivation for Yalies to conserve. As Yale President Richard Levin hands out glossy brochures of greenhouse gas goals to all of his official visitors, and as engineering-ignorant environmentalists like me push Yale and its students to achieve these goals, the reality stands here: in the 1200° fossil-fuel flames that continue to power our lifestyle.

In 2005, Levin announced his much-touted Greenhouse Gas Reduction Commitment, vowing to reduce Yale’s greenhouse gas emissions to 10 percent below 1990 levels (or 43 percent below 2005 levels) by 2020. Since Levin’s announcement, the University has showered anti-emissions efforts with publicity and funds. But the goal has come head-to-head with an even more pressing ambition: Yale is expanding at an unprecedented pace, adding more and more energy-intensive square footage to its campus. The commitment to greenhouse gas reduction is swimming upstream, and the current is only growing stronger.

Yet emissions reduction is hidden where we might least expect it. Despite the demonization of conventional energy production, Starr and company quietly wage their own battle to cut our carbon. Next to the big green box stands an even bigger gray box: another boiler, but this one is different. This cogeneration system, also known as combined heat and power, produces both electricity and steam from the same input of fuel—and, in doing so, cuts greenhouse gas emissions drastically. One of Central Power Plant’s three “cogen” units is shut down today for maintenance, Starr tells me excitedly, so I will be one of the few tourists to see inside a process that usually remains invisible. He opens a door to reveal the cool interior of the dormant cogen and points out a turbine, roughly the diameter of a bike wheel. Instead of directly powering a boiler, the burning of natural gas runs this gas turbine, which spins a generator to produce electricity. Meanwhile, the gas that powered the turbine still holds energy in the form of heat; the gas exhaust is about one thousand degrees. Here, the cogen kicks in: The hot exhaust is channeled into a boiler to make steam.

The cogen boiler is no different from the conventional boiler in the green box—except that it’s getting its heat from another source. “So the fuel that we burn here, we kinda get to use it twice,” Starr says. By the time the twice-used gas exits the boiler and heads up and out of the tall smokestacks, it has lost about 700°, leaving it at a modest 300. “We’re taking a huge amount of thermal energy out of that exhaust gas and making something useful out of it,” Starr boasts.

Cogen cuts down on both costs and emissions. Aside from its double use of fuel, the system allows Yale to produce much of its own electricity rather than rely entirely on the regional electric grid. Each of Central Power Plant’s three cogeneration units produces about six megawatts of electricity. Combined, that’s enough to power 300,000 standard light bulbs—or to cover about half of the electricity demand in Central’s coverage area, which includes all of Central Campus and Science Hill. The remaining half still comes from the utility company. By burning relatively clean natural gas (with ultra-low-sulfur diesel oil for backup), Yale significantly improves the environmental profile of its grid, which relies in part on highly polluting coal-burning plants. And although building a cogeneration facility requires a huge investment—$100 million for the Central cogen project—the system pays for itself in less than a decade.

Cogeneration is one of the cleanest ways to burn fossil fuel for power, but in the end, it is still burning fossil fuel. Yale these does not allow Starr and his colleagues to prioritize efficiency and emissions reduction; trying more experimental clean energy options takes place outside the plants, in settings that hold no risk of upsetting Yale’s power supply. Yale demands reliability, to a much higher standard than that of a typical utility.

Coming from the commercial utility business, Starr found Yale “very, very different. In the commercial side it’s entirely about production costs,” he says. “And for the Yale community it’s reliability first and production costs second.” The Yale plants not only provide comfort but also run kitchens, medical facilities, and science labs that must maintain standards of temperature, humidity, and ventilation both to meet safety regulations and to sustain careers’ worth of experiments. Starr and his colleagues cringe at the mention of “That Day Last January,” when a construction accident caused parts of campus to lose power. “For an operation like this, the total integrated cost isn’t just the cost of operating and, you know, did you burn more or less fuel than you could have,” Starr says. “The total cost is what happens if this facility stops operating? What’s the value of the research work that’s lost? What’s the value of incurring damage to buildings? We provide the only source of heat to the Central Campus. So what happens to the buildings if we’re not able to provide heat in the dead of winter? There is an economic cost to that and it’s enormous. It’s huge!”

The big-picture measure of reliability is what is called firm capacity; that is, what would a plant be able to produce if its biggest unit shut down? For steam firm capacity, for instance, if Central’s biggest boiler broke, how much steam would we able to produce? And for electricity, how much could we produce using cogeneration alone if the grid went out, or, in reverse, how much could we take from the grid if our cogen shut down? A dependable power plant has built-in redundancy, with many machines running only to back up others. Redundancy not only insures against machine failure; it also allows workers to regularly shut down one set of machines for maintenance while another set fills in.

Yale’s cogeneration is not only an environmental measure but part of what Starr calls the University’s “very, very deep investments in assuring reliability.” Yale’s cogen electricity is cleaner and cheaper than the grid, but it is also more reliable. For Yale’s medical community, with its high concentration of research labs and medical facilities, the stability of cogenerated electricity has proved a crucial selling point. After witnessing a decade of successful cogen operation at Central Power Plant, its medical campus counterpart, Sterling Power Plant, is preparing to install its own, 15-megawatt cogen facility.

Aside from the occasional $100-million-dollar addition, the day-to-day work of assuring reliability consists of checking, cleaning, and replacing countless nuts, bolts, lights, pipes, and blades. Most of the work of running a power plant, Starr says, is “constant routine maintenance.”

As we talk in Starr’s office, which sits above the operations at Central Power Plant, two men in soot-smeared overalls saunter in; they have just cleaned a boiler. Starr looks them over. “It’s not as clean as it should have been based on the looks of you,” he says.

One answers, chest thrust out, “It’s a lot cleaner now, chief.” They launch into a discussion about baffle plates and crack stoppers. Once Starr is finished interrogating the men, he lapses into a thoughtful pause, then slips in one last question. “Drums looked all right?” “Yeah,” one man answers, adding slyly, “Other than being too small.” The other jumps in: “Can’t imagine—those holes just keep getting smaller.” They all laugh.

The drums, Starr explains, are the round hatches that lead into a boiler. “For licensing for the boilers,” Starr explains, “we’re required to do an inspection every year. That inspection is very, very invasive. Those two guys have just crawled through the boiler from one end to the other on what’s called a fireside, which is where the hot gas is, and then through the headers where the steam is actually collected…. So anything that could potentially be wrong with the boiler is caught with an inspection like this before it actually manifests itself in a failure of the equipment.”

Down in the plant, Starr displays evidence of the massive scale of plant maintenance. He points out a chiller that is opened up for cleaning, a large cylinder that contains 15,000 25-foot-long metal tubes. The tubes hold water, which is chilled by a refrigerant and then shipped campus-wide to buildings for air conditioning. But the inside walls of the tubes collect deposits, which impede the transfer of heat from the water to the refrigerant and make the chiller less efficient. Starr reaches into a nearby box and picks up a stiff, blue, giant-pipe-cleaner of a brush. Once a year, workers must run such a brush down the entire length of each of the 15,000 tubes—twice. And this is just one of five chillers in Central Power Plant.

Knowing my biases, Starr has shown me the chiller cleaning process to teach me a lesson. While I’m busy worrying that reliability trumps efficiency at Central, its engineers see efficiency in every detail of the plant, on scales both minute and grand. And such an eye to efficiency doesn’t always clash with the plant’s more urgent priority of reliability: Sometimes, efficiency and reliability work together. At the end of the day, running a blue plastic brush down 15,000 25-foot-long tubes is, in terms of emissions reduction, one of the best things we can do.

As much as Yale demands of its power plants, it doesn’t exactly roll out the red carpet for them. At Sterling Power Plant, an easy-to-miss complex on Congress Avenue, Assistant Manager Jess Muir points out a second-story window to a concrete lot below. “See that? Underneath there is a 3.5-million-gallon tank.” The underground tank, once used to store chilled water, has stood empty for years and now sits beneath a parking lot and a tennis court. Soon, the tank will hold two huge cogeneration units. Each will produce 7.5 megawatts of electricity and save 20,000 metric tons of carbon equivalent a year—comparable to the emissions of over 3,500 cars.

“Imagine a regular truck container,” says Muir in his sharp, energetic Scottish accent. Each cogen unit is “slightly bigger than that. It’s basically a jet engine in a box.” Two jet engines, each in a box, all inside a bigger box, underground: It sounds potentially disastrous. Extracting some of the equipment for repairs, Muir admits, could get tricky, but there aren’t many other potential cogen sites on Yale’s crowded and ambitiously expanding campus. Witnessing the efforts needed to get permission to raze the tennis court, Muir learned a valuable lesson: When the Yale community demands energy, you make it happen—but it better not get in anyone’s way.

Take, for instance, the new chiller plant, now slated for a site in Science Park, which will allow the University to more than double Central Power Plant’s peak air conditioning production. Even after the project’s benefit had been acknowledged, it wasn’t easy to secure the property. “That facility had to compete with a lot of other building plans for the site,” says Sam Olmstead, Yale’s head of Utilities Engineering. “It’s not like we’re going to bump a classroom for a chiller plant. So finding a home for it was challenging.” Classrooms trump chiller plants, but classrooms also need chiller plants. The problem stems partly from the limited local space available for Yale’s Manifest Destiny, and also from an attitude that urban planners call, “Not In My Back Yard.”

“NIMBYs,” scoffs Tom Downing, Yale’s senior energy engineer. Downing’s office, cluttered with diagrams of fuel cells, brochures for evacuated solar tubes, and a thin-film photovoltaic solar panel leaning against one wall, reveals an obsession with alternative energy that exceeds his job description. He directs his NIMBY comment toward Yale’s reluctance to place wind turbines anywhere visible on its architecturally finicky campus. The same term applies to anything from sewage treatment plants to power plants. Everybody needs them, but nobody wants to see them.

But wind turbines and solar panels, both visually iconic clean energy sources, should hold the most potential for overcoming NIMBYism. They are something to show off—especially considering the publicity attached to Levin’s greenhouse gas commitment, the strategy for which emphasizes on-campus renewable energy installations. Downing wants to create space, both aesthetic and geographic, for the projects that Yale theoretically supports. As the planning begins for the two new residential colleges and the new School of Management campus, Downing, along with Olmstead and others, is pushing for designs that will be amenable to installations like wind turbines. Currently, Downing is in the process of installing a series of ten micro-wind turbines—the plan for which, after being bounced around Science Hill in a game of blueprint hot potato, has finally found a future home on top of Becton. Not as visible as Downing would have liked, but it’s better than nothing.

But micro-wind turbines won’t get Yale to its emissions goal any faster than will brushing out 15,000 chiller tubes. At one kilowatt (that’s one-thousandth of a megawatt) each, Downing’s turbines might cover at most 5 percent of Becton’s energy consumption. As everyone agrees, there is no silver bullet, but instead a mix of many small solutions that, together, start to add up.

Still, “small” is a relative term. Yale could have installed a hundred micro-turbines by now, instead of a barely-approved plan for ten. The “no silver bullet” mantra serves as a convenient excuse, hiding the nagging suspicion that Yale isn’t willing to make big sacrifices to reduce energy use or to rethink the way it consumes and expands. Is Yale making the changes necessary to reach its celebrated goal?

“I don’t know,” Muir responds. “I don’t see it. All I see is these numbers here.” He gestures to his computer screen, where an endless spreadsheet records Yale’s energy production data: 6.5 million cubic feet of natural gas burned in a single day this summer, producing 17 megawatts of electricity, 17,000 tons of chilled water, and 5.5 million pounds of steam—and that’s just for Sterling Power Plant. Starr is more political than Muir, but no more optimistic. “I don’t see any ability to meet needs in a non-conventional fashion,” he says. Starr is overseeing the installation of two new conventional boilers at Central Power Plant. As tempted as I am to condemn them, there is nothing wrong with the boilers themselves. They will be the most efficient models around, and, like the new Science Park chiller plant, they’re wanted partly to increase firm capacity. The boilers themselves aren’t causing Yale’s skyrocketing steam consumption; they are only answering it.

All new Yale buildings must now meet the widely used LEED standard for sustainable design, but even LEED-certified buildings use a substantial amount of energy: More development means more power plant demand. Planners like Downing and Olmstead must do what they can, given the no-arguments-allowed expansion plans that land on their desks. “All of our reductions have to take place against that backdrop,” says Olmstead.

“We’re very keenly aware of the energy we’re producing,” Muir laments, “but it’s our job to produce whatever is needed.” And Yale needs a lot. “My ultimate goal,” Muir continues with a frustrated yet hopeful smile, “would be… to walk out of here, lock the door and say, ‘You don’t need me anymore.’ I would love nothing better than to shut down all this polluting equipment.”

Yale’s Utilities and Facilities Departments claims some of the University’s truest believers in reducing emissions. Energy professionals, more than anyone, see the dirty underbelly of consumption—and the darker side of Yale’s obliviousness.

Muir and Starr don’t just want the Yale administration to pay more attention. They want individuals to reduce their personal consumption—and also to speak up, to call out the University when it lapses and to push for change. “You see windows open during winter, you see windows open during summer when you know the air conditioning’s on—and it just kills you,” says Starr.

The “open windows” refrain, which echoes through the ranks of Yale’s energy engineers, is a criticism more profound than it might seem. Open windows are both a symptom and a cause of energy-inefficient buildings. Buildings with antiquated temperature controls or drafty windows and doors run heating systems unevenly and thus inefficiently; when people in the hot parts of a building open windows, the building senses colder air and responds by pumping in more heat. The guilt lies both in the decision to open a window and in the failure to demand better heating systems in Yale’s buildings, resulting in what Muir calls “energy pissed away.”

“Open windows” is code not for laziness but for blindness. Because Yalies don’t see the systems that serve them, they don’t think of an overheated building as something to question. But they do see it as a bother.

Meanwhile, John Higgins is watching from the systems side that Yalies do not see. Higgins, Yale’s Systems Engineer, oversees the programming of the University’s increasingly sophisticated HVAC (heating, ventilation, and air conditioning) climate-control systems, which determine the flow of steam and chilled water from the power plants to buildings across campus. The HVAC systems of separate buildings are linked through a web-based central computer program called Backnet. Higgins opens Backnet and pulls up my college, Jonathan Edwards. It’s a fairly simple diagram showing the flow between valves, pumps, and heat exchangers in the college. “Delta T is twelve degrees,” Higgins announces with satisfaction, referring to the temperature change of the building’s hot water. Then he turns to me to make sure: “Is it comfortable?”

Higgins describes himself as “not a rock-the-boat person,” which makes him well-suited to his job. Like production in the power plants, climate control is supposed to be invisible. “HVAC is one of those things—no one ever calls you up and says you’re doing a good job. So if you don’t hear from a building you figure it’s running pretty well.”

Higgins’ assumption is understandable, but is it valid? As long as Yale’s energy engineers keep doing their job, the enormous costs and emissions associated with energy consumption will remain invisible to those whose behavior determines demand and thus dictates the mechanics of building control. But how can the mechanics side talk back and change this behavior?

The question points to a truth that echoes in the words of Muir and others: while Yale’s chiller tubes may be running smoothly, the channels of communication remain plugged. Most of the time, communication is a one-way street. While inside the power plants, Yale’s demands ring loud and clear, Muir’s and Starr’s message to the Yale community barely makes it past the power plant gates. On the other side, Yalies become aware of the energy system only when it doesn’t work for them—and then they “talk back” to the system by opening a window. Yale’s energy makers and energy consumers are largely alien to each other. Someone must bridge the gap between them—and that someone may be those who, for now, largely represent the problem: Yale’s students.

Last year, with the help of Bob Ferretti, the Education and Outreach Manager at the Yale Office of Sustainability and my former supervisor, STEP pushed for modest improvements that would bring potentially big energy savings. Capping the few chimneys left open around campus and insulating drafty windows and doors are the easy measures, the “low-hanging fruit” that Yale has yet to pick clean. STEP took its case all the way to John Bollier, the powerful associate vice president of Facilities. The work paid off. “We are tightening the envelope,” Ferretti assures me, and “it wouldn’t have happened without STEP.”

As part of the team that approached Bollier, I was surprised to find that he took us seriously. He didn’t just humor us. He listened intensely to our ideas and, when he approved, made things happen. Having grown accustomed to a campus where, over centuries, tradition has deposited resistance to change in every nook and cranny of Yale’s operations, I thought his response something of a miracle.

Strangely, STEP has been most effective not in changing student behavior—the original goal of group— but instead in changing Yale’s mechanical systems. But these mechanical changes are themselves a form of behavioral change—one that, unusually, brings administrators, engineers, and students all to the same table. And in building these new channels of communications, students are proving the keystone. Ferretti helped me understand: Bollier listened to STEP not because we were experts but because we were students, talking with him face-to-face.

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