“A CLEAN ENERGY FUTURE FOR THE UNITED STATES: THE CASE OF GEOTHERMAL POWER”. Testimony by the President of Iceland Olafur Ragnar Grimsson at a Senate Hearing Committee on Energy and Natural Resources”. US Senate. 26 Sept. 2007 – 3. GEOTHERMAL UTILIZATION Although geothermal energy is categorised in international energy tables among the “new renewables”, it is not a new energy source at all. People have used hot springs for bathing and washing of clothes since the dawn of civilisation in many parts of the world. Late in the nineteenth century, people began experiments utilizing geothermal energy for outdoor gardening and early in the twentieth century, geothermal sources were first used to heat greenhouses. Around the same time, people started using geothermal energy to heat swimming pools and buildings. Electricity has been generated by geothermal steam commercially since 1913, and geothermal energy has been used on the scale of hundreds of MW for five decades now, both for electricity generation and direct use. The scale of utilization has increased rapidly during the last three decades.