Over the past few days we have featured a couple of different stories about geothermal energy. The first recapped two of the main sources (deep well drilling for electricity generation and ground source for home heating and cooling). The second gave you a homeowner’s perspective. Today we bring you another take on geothermal. Ball State University in Muncie, Indiana (alma mater of David Letterman) has implemented a plan to power the school with geothermal.

According to the Christian Science Monitor, “3,750 to 4,000 wells will be dug to supply heating and cooling to most (more than 45 of 50-plus) buildings on the 660-acre campus.” The university’s system will rely on the constant temperature found below the earth’s surface – ground source geothermal.

In winter, cold water will flow to the fields and down the wells to absorb heat from the surrounding earth, which stays in the 54- to 55-degree F. range year-round. Water warmed by the wells will flow back to a heat exchanger that collects and concentrates the warmth to heat buildings.

To cool those same buildings in summer, the process reverses: Water warmed by the heat exchanger is cycled into the wells, where it is cooled by the surrounding earth. While pumping all that water requires electrical power, the thermal energy harvested by the system is four times greater than the energy the system consumes. Overall, the project will save an estimated $2 million annually in fuel costs while halving the campus’s yearly carbon dioxide emissions – an 85,000-ton cut.

One of the main obstacles to geothermal systems of this nature and size is the initial capital outlay. Ball State’s president, Jo Ann Gora, is interviewed in the article as saying that during the $41 million (US) first phase of the project, “two of Ball State’s four coal-fired boilers will be replaced with geothermal heat pumps. But eventually all will be replaced for a total cost of about $70 million over the course of the five- to eight-year project.” Due to fuel costs, geothermal will be less costly in the long run. President Gora said that the coal-boiler manufacturers claimed “‘that there was no way they could produce these boilers without it costing us $65 million.’”

According to NPR, “Unlike wind and solar, which don’t operate efficiently 24/7, geothermal systems are on all the time. But each one must be installed on-site, meaning it would take thousands of these projects to equal the heating and cooling power of just one coal plant.” Of the $71-80 million price tag (the latter number comes from NPR), $40 million will come from the state and $5 million from federal stimulus funds. However, NPR reports that the school “has raised just over half the money it needs.”

If the school needed any confirmation of their decision, the fact that they burn through 130 tons of coal a day should be impetus enough to force a change away from this nonrenewable resource. Ball State stands out as a leader and innovator that is paving the way toward a clean energy future.

- Eric Wilson

[image source: NPR]