Geothermal energy in 2007 supplied only 0.3% of global electricity demand which is way too little if you know that the amount of heat within 10,000 meters (33,000 feet) of Earth's surface contains 50,000 times more energy than all the oil and natural gas resources in the world. Geothermal energy definitely has the great potential and should be more widely used. By using more geothermal energy world would decrease the dependence on fossil fuels which would be more than helpful in fight against climate change.
Geothermal energy could play much bigger role in supplying global energy demand in years to come than this is the case today. Geothermal energy is non-carbon based energy source that is environmentally friendly, and doesn't release harmful greenhouse gases into the atmosphere. Almost all energy experts agree that geothermal energy is very large resource and has more than enough potential to satisfy energy needs of large part in the world.
Some scientists have calculated that with the proper development in technology, geothermal energy could provide as much as 20 percent of world's power by the year 2050. This is only the fraction of enormous potential that geothermal energy has but sadly much of this potential will not be exploited in coming decades due to the profitability issue. With current technologies only small fraction of Earth's geothermal resources are profitable for exploitation and harvesting energy. This areas are called "hot spots" that occur at plate boundaries or at places where the crust is thin enough to let the heat through. Drilling and exploration for deep resources costs tens of millions of dollars, and success of drilling in terms of profit is really only guaranteed at these hot spots.
The drilling costs are main problem why geothermal energy isn't more widely used source of energy. As said before drilling costs can reach tens of millions of dollars because drilling has to be done deep in the Earth, in some cases 5,000 feet or more below the earth's surface. When you think of it, the story with geothermal energy potential is really quite simple, the more profitable this energy source becomes in years to come the more potential it will show. Current drilling technologies will definitely not help geothermal energy to show us much of potential, and the drilling technology will have to be much more advanced before we see much wider use of geothermal energy.
United States, for instance has excellent geothermal energy potential, and some studies have shown that geothermal energy could one day supply nearly all of today’s U.S. electricity needs. In order to do so EGS (Enhanced geothermal system) technologies would have to significantly improve. The EGS working principle is to extract heat by creating a subsurface system. After this system is created water can be added to this system through injection wells. Injected water is heated by contact with the rock and returns to the surface through production wells, as in naturally occurring hydrothermal systems.
Hopefully, with more improvements in EGS technology geothermal energy projects will cover much wider range in years to come. Geothermal electric plants have until recently been built exclusively on the edges of tectonic plates where high temperature geothermal resources are available near the surface, where the drilling costs are not too high. Could EGS technology turn geothermal energy into one of the most important energy sources in years to come? Well, geothermal energy has almost unlimited potential, and the only thing that is really missing is adequate technology to exploit this potential. The future years will show us whether EGS is really the adequate technology for exploiting geothermal energy potential or not.