Geothermal: Power Now !

[irishbobcat]

The new Brookfield K-12 school complex will be using geothermal heating as their main source of energy when completed around 2009-2010.

Dennis Spisak

[Towntalk]

The PBS program "This Old House" did a program on heating a large house with geothermal equipment and natural gas with the natural gas as a backup and their expanation made a whole lot of good sense. During most of the year the homeowners used the natural gas for cooking, and it was only during the winter months that the natural gas supplemented the geothermal heating system which means that the homeowners had really low gas bills.

The geothermal unit sat in back of the house out of the way, and with shrubbery around it, out of sight.

http://www.thisoldhouse.com/toh/article/0,,20162296,00.html

[irishbobcat]

Geothermal Energy: Power from the Earth…NOW!

June 24, 2008

Geothermal energy is not glamorousâ€"its plants look more like coal-fired power plants than sleek, modern wind turbines or space-age solar mirrors in the desert.

But don't judge geothermal by its steam stacks.

Geothermal is used commercially in more than 20 countries (more than 70 if you count ground source heat pumps) and generates more than a quarter of the total electricity used in Iceland and the Philippines.

The U.S. is the world's leading geothermal energy producer, though geothermal generates less than one percent of America's total electricity output.

The Promise

Geothermal has one main advantage over today's leading renewables: it is not dependent on a sunny or a windy day. It is available virtually 100 percent of the time and therefore doesn't require a back-up fossil fuel power plant or energy storage capacity.
Geothermal is clean and safe. At facilities like the Geysers, where wastewater is reinjected back into the ground to replace the extracted steam, it is also sustainable. And it can be scaled up to generate power for major metropolitan areas.
Geothermal's potential is enormous. The amount of heat within 10,000 meters (about 33,000 feet) of Earth's surface contains 50,000 times more energy than all the oil and natural gas resources in the world.
The National Renewable Energy Laboratory estimates that geothermal could provide between 4 and 20 percent of current U.S. electricity needs by 2025. It is already price competitive with coal-fired power plants in many places.

The Challenge

While geothermal heat occurs everywhere, the most easily accessible geothermal resources are naturally occurring hot springs at or near the Earth's surface. These geological features are found on less than 10 percent of Earth's land area.
Today, there are three ways to harness geothermal energy, all of which require access to a hot springs or hot wastewater.

1.If the hot water reaches the surface as steam, it can be harnessed to drive an electric turbine. This is called a "dry steam" system.

2.If the hot water remains a liquid at a high enough temperature, it can be "flashed" into steam and then used to drive the electric turbine. This is called a "flash steam" system.

3.If the hot water is not hot enough to be flashed directly into steam, it can be used to flash another liquid with a lower boiling pointâ€"such as ammoniaâ€"and the resulting steam is then captured in turbines. This is called a "binary" system.

Advancements in binary systems have opened new opportunities to access "moderate temperature" geothermal resources, which are far more common than high temperature resources.

The Chena Hot Springs power plant near Fairbanks, Alaska, is the lowest temperature geothermal resource to be used for commercial power production in the world.

Thanks to breakthroughs at Chena, the cost of power production from these moderate temperature resources has been reduced from 30¢ to less than 7¢ per kWh. That low price opens up the option of using waste heat resources, like the water that comes up at oil wells, as free fuel.

Researchers are also studying ways to capture heat in dry areas, know as "hot dry rock." This involves drilling deep into the earth's surface using technologies developed by the oil industry, then injecting water down to the hot rocks and bringing the hot water back to the surface to drive turbines and generate energy.

Several projects using this technologyâ€"called enhanced geothermal systems (EGS) or heat miningâ€"are under development in France, Australia, Japan, Switzerland and the U.S. The race is on to establish the world's first commercial hot dry rock power plant.
Many geologists are concerned about possible seismic consequences connected to drilling through the earth's surface to access hot dry rock resources. In 2007, a geothermal power plant in Switzerland triggered an earthquake that registered 3.4 on the Richter scale.

Another major barrier is the cost involved in finding viable geothermal resources. The only current way to test for geothermal properties is to drill deep holes. This is expensive and increases investment risk.

The Future

There are several areas of research that could soon make geothermal energy a more widely available and efficient resource.
Researchers are working to:
·Make testing a potential geothermal location more economical, reducing the risk of investing money in "dry holes."
·Make the current binary geothermal systems more efficient to tap cooler hot springs where direct and flash steam plants are not possible. Breakthroughs at the Chena Hot Springs location offer tremendous promise in this area.
·Make the energy grid more efficient and develop transmission capacity to open up remote, and currently "stranded", geothermal resources.

Some analysts believe the big breakthrough in geothermal energy could come when enhanced geothermal systems (EGS) become economically competitive, allowing "heat mining" close to centers of demand, like big cities.
A 2006 study by MIT researchers found that "none of the known technical and economic barriers limiting widespread development of EGS as a domestic energy source are considered to be insurmountable."

The study concluded that EGS could generate 100 gigawatts or more in the U.S. by 2050. And it calculated the world's total EGS resources to be sufficient to provide all the world's energy needs for thousands of years.

As with all renewable energy resources, setting a cap on global warming pollution and pricing carbon emissions into the market is the key to creating economic incentives to finance and mainstream geothermal energy production.

As the Green Party Candidate for State representative for the 60th District, my goal is to go to Columbus and work with private industry and state leaders to let them know that geothermal energy will be a cost competitive within their planning horizons and that poor, working, and middle class want to get serious about planning for large scale geothermal deployment now.

Dennis Spisak-Independent Green Party Candidate for State Representative-60th District
Campaign site: Http://votespisak.tripod.com