Green Power


Colby taps geothermal energy, clean electricity to meet environmental responsibilities.

By Alicia Nemiccolo MacLeay '97

It takes a lot of electricity (approximately 14 million kilowatt hours per year) to run Colby College, with its 1,800 students, 24-7 computer labs and more than 60 buildings. But, as of October, no fossil fuels were being burned to generate the electrical power that Colby purchases to keep lights burning and desktops humming. Half of the electricity now comes from Maine hydropower and the other half from Maine biomass, such as wood chips and sawdust.

Constellation NewEnergy, working through the not-for-profit energy-purchasing consortium Maine PowerOptions, is providing Colby electricity produced by Maine generators and businesses. The College had been seeking an environmental power package for several years and signed on with Constellation NewEnergy this fall because its package was the right fit, says Patricia Murphy, director of the Physical Plant Department (PPD). "We'd been offered other packages before," said Murphy, "but none of them seemed to meet our needs as well as this one." Murphy says the Constellation NewEnergy package was chosen because it was completely "green," competitively priced and 100 percent from Maine. "We felt that the support for the Maine economy was an important factor."

Previously, 30 percent of the energy that Colby purchased came from hydropower and 70 percent from coal-burning plants. With the new electricity package, nitrogen oxide emissions, which cause smog, will be reduced 41 percent and sulfur dioxide emissions, which cause acid rain, will be reduced 98 percent. Hydropower produces no carbon dioxide (CO2) emissions, which cause global warming. Biomass is considered CO2 neutral because CO2 released during biomass combustion is equal to the CO2 absorbed by plants during their growth cycle, and plants produce CO2 whether they are burned or allowed to rot.

Tom Tietenberg, Mitchell Family Professor of Economics and an international expert on environmental economics, emissions and climate change, says the College's commitment to purchase only electricity generated from renewable, more environmentally friendly sources already has had a stimulating effect on the market for green power choices. "An important part was that Colby was actively seeking these commitments and thereby helping to make the market even before suppliers had surfaced," said Tietenberg. "Colby's role is really very important in making sure that other institutions now have green power choices."

Green power is just the latest initiative in a campaign at Colby to use environmentally friendly energy sources, which Tietenberg says has recently "taken on renewed vigor." Since 1999 Colby's own steam plant has provided approximately 12 percent of the College's annual electricity through co-generation,an innovative system in which steam for heating campus buildings spins a turbine to produce kilowatts on its way through the Colby system. Co-generation produces an average of 1.7 million kilowatt hours of electricity annually, saving Colby more than $150,000 in power purchases each year.

And in the same month that the power contract was signed, three geothermal wells were drilled to provide heating and cooling for a new 27,000-square-foot alumni center to be built on campus beginning next spring. Colby Green Project Manager Steve Campbell (PPD) says geothermal heating and cooling is relatively new, so the public doesn't have much understanding of it.

According to Campbell, it took about four days to drill each of the six-inch-wide, 1,500-foot-deep wells and another half day just to pull the drill casings out. Geothermal wells work for both heating and cooling because the water temperature at 1,500 feet below the ground stays consistently in the middle to upper 50s. When that water is pumped up into the building in the summer it is cool compared to ambient air temperatures and it helps cool the building; in winter the water is relatively warm and heats the building as its warmth is transferred to the liquid in the building's heating and cooling systems.

Tietenberg, who has conducted climate change research with the United Nations for more than a decade, says it is important for institutions like Colby to lead by example in reducing greenhouse gas emissions. Reduction will not only decrease environmental degradation but also will help to foster national security by reducing dependence on imported fuels. Being a leader in this area has other benefits for a college, Tietenberg says. "An increasingly large number of prospective students are using environmental leadership as an important criterion in their selection of colleges to attend," he said.

This fall Colby became a Green Power Partner with the U.S. Environmental Protection Agency, which recognized the College's commitment to cleaner, renewable and reliable alternatives to conventional electricity generation. The College also is a supporting organization of Maine Green Power Connection, a network of businesses, organizations and residents working to create a viable market for greener electric power in Maine.

"Educational institutions have always been agents of change in part because effective change requires new information," Tietenberg said. "Changing the way we operate will be necessary if we are to prevent altering our planet in ways that we can now only dimly perceive."