Friday, February 2, 2007

GEOTHERMAL FEATURE: Heat Rises

Atlantic Geothermal’s Dave Reynolds is not reinventing the wheel; he’s building a coach from spare parts left lying around for years by the oil, gas and mining industries. In other words, as has been said already, the technology exists today to make the United States energy independent, perhaps indefinitely. How? By tapping into the heat that lies beneath our feet. If it’s done right, Reynolds claims, the energy obtainable from hot rocks is sustainable for centuries, does not require burning fossil fuels, will not pollute the environment, runs 24 hours a day seven days a week, can provide an unending supply of fresh water from sea water, and is not only achievable but affordable at today’s energy prices. His argument is compelling.

Sure, there are obstacles to overcome, questions to be answered. For example, how clean is it? Atlantic Geothermal advances a feasible design solution to concerns about mineral pollutants leached from subterranean rock. Could extended development of geothermal energy cause earthquakes? Well, listen folks, what they’re doing now, drilling into fissures between tectonic plates to mine readily available steam, does not fill me with reassurance. Atlantic Geothermal is advancing a project to run steam turbines on heat mined from almost anywhere within 100 miles of the ocean — specifically, New England, which is not considered a hotbed of geothermal capacity, nor of earthquakes.

The landmark MIT report on potential geothermal resources, released January 22, demonstrates with mountains of data that “enhanced geothermal systems” (EGS) can meet up to 10 percent of the nation’s current and projected electricity needs by 2050. This amount would replace the generating capacity that will be lost by the expected retirement of old coal-fired and nuclear generating plants.

Atlantic Geothermal’s visionary project leapfrogs the 30-year continuous operating life expectancies of EGS plants by greatly expanding the hot rock energy field. By drilling an 80- to 100-mile-long, 50-ft.-wide tunnel three miles below the surface, then expanding bore holes 1500 ft. laterally, the project could realize an energy field potentially 3,000 ft. wide and 80 miles long. Reynolds projects that one such system could generate 1600 megawatts of power per hour — 16 times the output of a large conventionally designed EGS plant, and nearly matching the output of Hoover Dam. And, due to the greatly expanded heat reservoir of a field that size, the generating capacity would last indefinitely. Land use concerns? Except for the input and output facilities, the entire system is three miles underground, maintained by hydrostatic pressure.

It bears repeating that the know-how exists today to bring Atlantic Geothermal’s vision of perpetually sustained clean energy into reality. All it takes is political and economic willpower. What are we waiting for?

by Loren Jenks (lorenjenks@charter.net)