There are two major types of geothermal energy. There is a decided difference between geothermal heating for one home, and geothermal electrical generation on a large scale.

The letters GSHP stand for ground source heat pumps. This is a unit that any consumer can have installed in their homes by a qualified contractor. A GSHP system can help with individual carbon footprints, and it can reduce a consumer’s energy bills – so it’s a great renewable energy product to have on the market.

These systems are appropriate for one home, for a development, or for larger projects such as government buildings and schools. There is one such project currently going up at the Bald Eagle Middle/High School in Wingate, Pennsylvania, with the help of the American Recovery and Reinvestment Act of 2009.

The actual installation of the geothermal energy will be quite a task, involving nearly 220 wells, each reaching 500 feet deep. They have three rigs hard at work into the fall last year, drilling at a pace of six wells per day. One amazing advantage to the heating system is that once the wells are in place, a practice field will cover them over, and the local school can go back to utilizing the space for day to day activities… while the very earth beneath their feet steadily heats the buildings around them. And it should save the district around $130,000 a year.

Image from Bald Eagle Area School District web site.

However, GSHP (when considered within the larger-scale environmental and energy problems we are facing as a society) is only one piece in the renewable energy puzzle. If we want to provide effective energy solutions, we will need to provide the full picture, and that will require many other important pieces.

The geothermal solution won’t come solely from individual home upgrades; it will come from large-scale change within the energy industry.

Large-scale geothermal

The Geothermal Energy Association (GEA) says that 3040 MW of geothermal power was generated in 2008 - that is enough to power ten cities the size of Pittsburg. And as of March 2009 there were geothermal projects in development all over the country with the potential to generate 5,500 MW.
The other piece of the puzzle is large-scale geothermal projects that feed the public utilities.

These plants run on the same basic principle as the home-scale ones or the ones used at the Bald Eagle School, but on a much larger scale. Instead of drilling down hundreds of feet crews drill down thousands.

And instead of using heat pumps, they tap into pockets of super-heated water and then channel the steam through turbine generators similar to the ones used in hydroelectric dams. Once the steam rushes through the turbine generators it is re-captured and pumped back into the underground reservoirs. Earth’s natural processes heat the water again, forming a renewable cycle of electric generation.

A major power purchase agreement (PPA) was just signed between U.S. Geothermal Inc. and the Idaho Power Company which will provide at least 25 MW of this type of energy to Idaho residents, enough to power 17,000 homes for a year. The actual geothermal site will be located in Neal Hot Springs in eastern Oregon.

U.S. Geothermal has already drilled two successful production wells, and the entire project is the result of cooperation between two states, a utility company, a geothermal company, and federal funding. This type of project, with the potential to put 35 MW on the grid 24-hours a day for the next hundred years, is precisely what we all need if we are going to provide clean domestic energy to our homes and businesses.

The GEA originally set its goal at 15,000 Megawatts by 2025, but if the industry continues at its current pace then this goal will be reached and exceeded.