Iceland went from being one of the EU’s poorest countries to one where almost all of the energy comes from renewable sources. Geothermal sources account for 66% of Iceland’s primary energy use. Iceland is in an area with multiple volcanoes, tectonic plates bring the heat to the surface. It’s location and focus on the research of harnessing renewable geothermic energy has allowed iceland to become a world leader in the field.
Lacking a national grid, Iceland harnesses energy by digging into the ground. By drilling a few metres underground, power plants can harness geothermal energy. The heat is constant due to their location. The large amount of heat sources in the country allow the vast majority of the country to be powered by geothermal energy.
Georthermal energy is low cost and creates no pollution, it is more effecient and cleaner than all of the non renewable methods used in the world.
http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/how-geothermal-energy-works.html#.VmDduNKrTcc
http://www.renewableenergyworld.com/geothermal-energy/tech.html