Investigating ultra high-enthalpy geothermal systems: a collaborative initiative to promote scientific opportunities

[摘要] Scientists, engineers, and policy makers gathered at aworkshop in the San Bernardino Mountains of southern California in October2013 to discuss the science and technology involved in developinghigh-enthalpy geothermal fields. A typical high-enthalpy geothermal wellbetween 2000 and 3000 m deep produces a mixture of hot water and steam at200–300 °C that can be used to generate about 5–10 MWe of electricpower. The theme of the workshop was to explore the feasibility and economicpotential of increasing the power output of geothermal wells by an order ofmagnitude by drilling deeper to reach much higher pressures andtemperatures. Development of higher enthalpy geothermal systems for powerproduction has obvious advantages; specifically higher temperatures yieldhigher power outputs per well so that fewer wells are needed, leading tosmaller environmental footprints for a given size of power plant. Plans forresource assessment and drilling in such higher enthalpy areas are alreadyunderway in Iceland, New Zealand, and Japan. There is considerable potentialfor similar developments in other countries that already have a largeproduction of electricity from geothermal steam, such as Mexico, thePhilippines, Indonesia, Italy, and the USA.

However drilling deeper involves technical and economic challenges. Oneapproach to mitigating the cost issue is to form a consortium of industry,government and academia to share the costs and broaden the scope ofinvestigation. An excellent example of such collaboration is the IcelandDeep Drilling Project (IDDP), which is investigating the economic feasibilityof producing electricity from supercritical geothermal reservoirs, and thisapproach could serve as model for future developments elsewhere. A planningcommittee was formed to explore creating a similar initiative in the USA.

[学科分类] 地质学