IEA WANTS MORE GEOTHERMAL

International Energy Agency Urges Greater Use of Geothermal Energy
June 22, 2011 (Sustainable Business)

"The International Energy Agency (IEA) is urging greater use of geothermal energy because of its ability to provide critical baseload power that's available all over the world, reliably every day of the year…Geothermal could increase 10-fold…with strong policies and incentives…[and account for 3.5% of annual global electricity production and 3.9% of energy for heat (excluding ground source heat pumps which the report did not consider) by 2050 - a substantial increase from current levels of 0.3% and 0.2%, respectively…

"Although there's been active geothermal exploitation for more than a century, those efforts to extract geothermal energy have concentrated on areas with naturally occurring water or steam, often found in volcanic areas…[but] Milou Beerepoot, the report's author and a senior analyst at the IEA, notes that a large share of such ‘low hanging fruit' remains unexploited in developing and emerging economies…"

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"…[G]eothermal energy can also be extracted from many deep aquifer systems, of which there are many all over the world. These resources can typically be reached at a depth of 3 kilometres and produce temperatures in excess of 60ºC. Use of these aquifers is expected to grow quickly, reflecting their wide availability and increasing interest in their use for both heat and electricity.

In addition…the vast majority of the world's geothermal energy within drilling reach - which can be up to 5 kilometres - is found in rock that is relatively dry and impermeable. These areas, which are found all over the world and contain insufficient water for natural exploration, are known as hot rock resources…[T]echnologies that allow energy to be tapped from hot rock resources - the best known is enhanced geothermal systems (EGS) - are still in the demonstration stage. The IEA report recommends that governments provide sustained and substantially high research, development and demonstration resources to plan and develop at least 50 EGS pilot plants during the next decade."

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"With these systems, a well is drilled deep into the ground, typically below 1.5 kilometres. Water is then injected into the well at sufficient pressure so as to create fractures in the rock. Other wells are then drilled to pump up the water, which has been heated by the hot rocks…

"Key areas of action for governments identified in the report are establishing targets and economic incentives for mature and nearly mature technologies as well as for advanced technologies that are not yet commercially viable…They also recommend streamlined and time-effective permit procedures [and other measures]…"