Wednesday, January 17, 2007

GEOTHERMAL FEATURE: New England Is Ready

By Christopher Sawyer-Laucanno

In June 2005, President Bush, made a pitch for building nuclear reactors as an alternative to coal and oil-fired generating facilities. “Nuclear power is one of America's safest sources of energy," said Bush. As usual, the president is off the mark. Even if Bush and company want to ignore that the potential for radiation leaks still exists, and that there are no viable long-term solutions for storing nuclear waste, his own Homeland Security folks have warned that nuclear plants are deemed serious targets for terrorist action. There is a reason that no new nuclear facilities have been constructed since 1979: they are neither safe, green nor reliable.

There is a true green alternative, however, to fossil fuel generating plants (and, of course, nukes). In Northern Europe, and on the West Coast, geothermal power production--which uses heat under the earth’s surface as a natural fuel source--is increasingly proving to be a real solution. California, in fact, is the national leader in the use of geothermal energy for electricity generation. Seven percent of the state's total power production output is geothermally generated. With its 41 working geothermal plants, California accounts for almost 40 percent of the total worldwide geothermal power production. The combined production capacity of approximately 1,900 megawatts of electrical power per hour is enough to supply nearly two million typical households. And new plants are underway.

Up until now, geothermal energy has been thought to be impractical for use in New England. In contrast to the Western United States, where massive amounts of heat lurk near the earth’s surface, in New England the heat is further underground. And yet, in New England, at just a depth of three to five miles, the earth’s temperature reaches about 300 degrees F., well above the temperature needed to boil water. As MIT professor Jefferson Tester notes, geothermal production is possible in New England due to advances in drilling technology that allow for heat extraction of depths up to 6 miles: “All the technology that goes into drilling and completing oil and gas production systems…could in principle be extended to deep heat mining. Hydraulic methods have been the ones that hold the most promise, where you go into the system and you pressurize the rock -- just water pressure.”

While Tester is interested in the math and theory of geothermal generation, Atlantic Geothermal, in Florence, Mass, a small visionary company founded by J. David Reynolds, is actively working to prove that geothermal power is viable for New England. Reynolds, who studied engineering at Northeastern, has devised a system that uses ocean water to power the turbines for making electricity. Reynolds’ plan is ambitious but given today’s drilling technology, far from impossible.

Reynolds calculates that a tunnel 50 feet in diameter, and some 80 to 100 miles long, would be needed to produce enough constant heat to generate 1,600 megawatts of electricity per hour

His plan, simply put, is to bore a tunnel from the ocean inland at a depth of about three or four miles. Geologic maps of coastal New England show that at this depth the temperature reaches at least 300 degrees F. Reynolds calculates that a tunnel 50 feet in diameter, and some 80 to 100 miles long, would be needed to produce enough constant heat to generate 1,600 megawatts of electricity per hour, nearly as much as that produced geothermally in all of California, or at the giant Hoover Dam that currently outputs 1,731 megawatts hourly.

He notes that the technology is here, the water is here, the heat is here. He also likes to point out that 100 years ago the state built a 25-mile long aqueduct from the Quabbin to Boston using mainly manual labor (his system uses robotic drilling equipment). And while he admits that it would be expensive, given the return of free power forever for a utility company, the cost could be absorbed within perhaps a decade. And it’s absolutely clean, absolutely renewable, with no waste by-products. In fact, the only by-product is desalinized water, which could also reduce dependence on the Quabbin and other reservoirs.

If industry buys in to Reynolds’ idea, New England’s dependence on dirty, non-renewable fossil fuels for electricity generation will be a thing of the past.