Cool ideas to cut energy use


Author: John Nagy ’00M.A.

The mercury hit 88 degrees outside Building 110 at the Indiana Dunes National Lakeshore on July 11, but inside the converted military blast shelter the thermostat was set at a cool 71 and a fan was blowing in the empty shower room.

Tom Furlong says he often found the temperature in that building set as low as 65.

The senior engineer-in-training was one of three Notre Dame students who lived for 10 weeks at the 15,000-acre Lake Michigan park near Chesterton, Indiana, performing energy audits and shaping recommendations to help the facility, administered by the National Park Service, consume energy more efficiently and cut its utility bills.

Conventional wisdom says our national parks, as exemplary stewards of the landscape and natural resources, shouldn’t have such problems. But conventional wisdom is wrong, say the park’s civil engineer, Susan Lehmann ‘97Ph.D., and Joan Brennecke, director of the Notre Dame Energy Center. Think instead of the parks as regular businesses with phones, computers, kitchenettes, the odd faulty light fixture and employees who occasionally thumb their noses at the management’s thermostat policy.

In some ways, Indiana Dunes is like a small town complete with a museum, a firehouse, cabins and dorms, public restrooms and laboratories run by the U.S. Geological Survey, each with unique equipment and regulations governing the use of water, electricity and gas heat. Building 110, for instance, serves as a garage, office and workout room for the fire crew, whose members are often working in the park and haven’t formed the habit of lowering the thermostat or flipping the lights off before leaving. Furlong and his partners found that electricity use per square foot is three times higher there than in other park buildings.

Think further of parks as understaffed businesses or municipalities that don’t have the time or manpower to crunch data and find cost-effective ways to conserve energy, and you understand the value of their on-site student consultants. Their work at the dunes lakeshore is part of the University-National Parks Energy Partnership Program, a decade-old alliance that offers the parks fresh eyes at a low cost and the students an interdisciplinary learning experience they can take back to campus, their homes and their careers.

Jackie Mirandola-Mullen, a junior, and Brian Klein ’08, both from the College of Arts and Letters, teamed up with Furlong to run appliances through hand-held energy meters, talk to park employees and take note of the gaps that add up to fuel wasted and dollars lost. They found, for example, empty refrigerators, staffers who complained of overly bright workspaces, a crack in the floor of park headquarters.

Mirandola-Mullen found the work tedious at times but instructive. She and Klein studied the feasibility of planting a green roof on Building 110: Native grasses or sedums that would help cool the concrete structure in summer, insulate it in winter, prevent stormwater runoff and reduce the exposures to weather and ultraviolet light that shorten a roof’s life. Assuming fuel costs remain constant—and most observers are betting they won’t—the students calculated the return on the park’s $50,000 installation investment at 37 years, a period notably shorter than the green roof’s 50-year life span.

Furlong researched the pros and cons of installing a ground-source heat pump at the park’s Paul H. Douglas Center for Environmental Education. He estimated that the sporadically used building, a series of inefficiently heated and cooled octagons, could lower fuel costs more than a third each year by switching from its conventional system to the pump system, which circulates water through a loop of pipes under the ground, where temperatures remain constant between 50 and 60 degrees. Heat transfers from the building to the ground in summer and from the ground to the building in winter.

Furlong says the pump would eliminate the need for natural gas at the center. The reduction would pay for the project in 20 years and save an additional $50,000 over the following five years.

While Lehmann and the other park administrators mull these costs and benefits, the team believes that simple fixes like tinted window films, ad hoc water heaters and consistent use of the park’s 68/78 policy—setting the thermostat at 68 in the winter and 78 in the summer, with 4-degree setbacks when the buildings are empty at night—would knock 9 grand off the park’s annual utility bills.

Computers cool local greenhouse
A similar partnership between the University and the City of South Bend is already saving money for both parties and may become a pilot for synergistic programs in other cities.

The idea was simple: Relocate several hundred pounds of computer servers from the University’s Center for Research Computing (CRC) to the Arizona Desert Dome of the Potawatomi Greenhouse, where natural drafts disperse the heat the computers emit into the dome’s warm, arid atmosphere.

At an Earth Day press conference announcing the project as part of the city’s “Cool Cities” commitment to reduce its carbon footprint 7 percent from 1990 levels by 2012, CRC engineer and Notre Dame professor Paul R. Brenner ’07Ph.D. said the University could save up to $100,000 in energy costs by not having to cool the machines with conventional air conditioning. The city, too, will trim tens of thousands of dollars off its annual heating bill.

This cool idea, by the way, came out of a neighborly chat Brenner had with the wife of a South Bend city councilman.

John Nagy is an associate editor of this magazine.

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