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Tapping geothermal riches

by grmeyers

Published March 25th, 2011 at 8:34 am in architecture, renewable energy with no comments
Tagged with Amasond, Department of Energy, geothermal, Merline Van Dyke, National Renewable Energy Lab, Renewable Energy World, Sims Construction, structural concrete insulated panel

This California geothermal power plant is one method of using heat from the Earth.

Use a banking analogy for the untapped and clean geothermal energy our planet provides to find we live on top of a remarkable energy safe deposit vault.
In 2008, geothermal power supplied less than one percent of the world’s energy. However by 2050 it is anticipated that geothermal power will meet between 10 and 20 percent of the world’s energy requirements, notes a report from Renewable Energy World.
Colorado engineer and geothermal innovator Merline Van Dyke says here are many different kinds of geothermal systems, some that rely on hot water from beneath the earth’s surface, others that simply use the constant temperature of soil below the surface as a means of heating and cooling.
“What I’m interested in talking about are the efficient ones,” says Van Dyke. He began experimenting with making homes more efficient in 1994, building a home in the foothills west of Denver, using structural insulated panels.
Van Dyke is presently working with Sims Construction, a Denver builder, as they finish a three-story, 2,400 square-foot geothermal house that uses structural concrete insulated panels (SCIP) on the exterior to maintain efficient temperatures. Net result: R-40 insulation value, an electricity bill that will run half of a normal bill, and no need for natural gas.

Source: Amasond

The house is located in central Denver and features an Amasond geothermal system. Amasond, an Austrian-based company, provided a geothermal system where pipe was drilled to a non-water level of 118 feet, where the earth temperature was a constant 52 degrees Fahrenheit.  This past summer, Sims flew to Europe to participate in an Amasond training program.
“I am very excited about how efficient this home is going to be,” he says, noting this is the first home of this kind to be built in Denver.

Understanding Geothermal Basics

Geothermal energy – or heat from the Earth – has been used in a variety of ways since the early annals of human life on this planet. Perhaps best, in this day and age, most geothermal energy is clean and sustainable, depending on what procedures are used. Hydraulic fracturing of rock below the surface, a procedure used in oil and natural gas capture, is being explored as a way to obtain hot water, but the environmental impacts to this procedure are being questioned by some. Resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the Earth’s surface, and down even deeper to the extremely high temperatures of molten rock called magma.

Merline Van Dyke and Richard Sims in front of Denver geothermal house using structural concrete insulated panels

A geothermal heat pump system consists of a heat pump, an air delivery system (ductwork), and a system of pipes buried in the ground near the building (see photo). In the winter, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system. In the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger. The heat removed from the indoor air during the summer can also be used to provide a free source of hot water.
The Department of Energy, working with the National Renewable Energy Lab (NREL) in Golden, CO undertakes ongoing research to develop and advance technologies for various geothermal applications.
Geothermal heat pumps use much less energy than conventional heating systems, since they draw heat from the ground. They are also more efficient when cooling your home. Not only does this save energy and money, it reduces air pollution. The GEO Exchange http://www.geoexchange.org/ is a trade association for geothermal heat pumps, an integral part of any geothermal system.
In modern direct-use systems, a well is drilled into a geothermal reservoir to provide a steady stream of hot water. The water is brought up through the well, and a mechanical system – piping, a heat exchanger, and controls – delivers the heat directly for its intended use. A disposal system then either injects the cooled water underground or disposes of it on the surface.

Geothermal Electricity

In 1911, the world’s first geothermal power plant had a capacity of 250 kilowatts. By 1975 the Larderello fields were capable of producing 405 megawatts of power. It was the world’s only industrial producer of geothermal electricity until 1958, when New Zealand built a plant in Wairakei. The Geysers Resort Hotel, California, was the site of the first geothermal power plant in the United States. The Geysers currently produces over 750 Megawatts of power annually.
Today, 69 geothermal power facilities are in operation at 18 sites around the United States, and geothermal power is generated in over 20 countries around the world.