Geothermal heat provides sustainable energy for electricity generation and heating applications. Worldwide use of geothermal energy has increased steadily over the past few decades (1, 2), and exploration and development are ongoing at unprecedented levels in Iceland, New Zealand, East Africa, Germany, Chile, and Australia. Today, 24 countries generate electricity from geothermal energy and 78 countries use geothermal energy for direct uses. Yet, geothermal sources still represent less than one percent of global energy production. The accessibility of geothermal resources depends on temperature and depth (see the figure). What are the limitations of geothermal energy extraction, and can the use of this resource be increased?
More Power from Below
Joseph N. Moore, Stuart F. Simmons
Science 24 May 2013:
Vol. 340 no. 6135 pp. 933-934