Tuesday, April 30, 2013

USA, California:

Workshop to Promote a Collaborative Initiative to Develop Higher Enthalpy Geothermal Systems in the USA

UCLA Conference Center
Lake Arrowhead, CA
October 13-16th, 2013

A workshop to discuss the formation of a U.S. consortium to systematically explore, assess and eventually develop higher-enthalpy geothermal resources will be held at the UCLA Conference Center at Lake Arrowhead in the San Bernardino mountains of southern California on October 13-16th, 2013.

For further information contact Wilfred A. EldersDepartment of Earth Sciences, University of California, Riverside, CA 92521-0423, U.S.A (wilfred.elders@ucr.edu).

Developing higher enthalpy geothermal systems for power production has obvious advantages; specifically higher temperatures yield higher the power outputs per well, so that fewer wells are needed, leading to smaller environmental footprints for given sizes of power plants.

Disadvantages include the fact that locations of suitable geothermal systems are restricted to young volcanic terrains, production of very high enthalpy fluids usually requires drilling deeper wells and may require EGS technology, drilling deep into hot hostile environments is technologically challenging and is therefore more expensive.

However the potential for very favorable economic returns suggests that the USA should develop begin developing such a program.

One approach to mitigating the cost issue is to form a consortium of industry, government and academia to share the costs and broaden the scope an investigation.  The Iceland Deep Drilling Project (IDDP) represents an excellent example of such a collaboration. The IDDP is investigating the economic feasibility of producing electricity from supercritical geothermal reservoirs. In 2009 to test this concept an industry-government consortium planned to drilled a deep well in the volcanic caldera of Krafla in NE Iceland. However drilling had to be terminated at 2.1 km depth when 900°C rhyolite magma flowed into the well. The resultant well was highly productive, estimated to be capable of generating >35 MWe of dry superheated steam at a well-head temperature of ~450°C. In the future it  may be feasible to  produce energy directly from magma. In 2014 the IDDP plans to drill to a depth 4.5 km in the Reykjanes geothermal field in SW Iceland to renew the search for supercritical geothermal resources.

Plans for deep drilling to explore for deeper, much higher enthalpy, geothermal resources are already underway in the Taupo Volcanic Zone of New Zealand (Project HADES), and in Japan where the “Beyond Brittle Project” (Project JBBP) is an ambitious program attempting to create an enhanced geothermal system (EGS) in ~500 °C rocks. However in the USA there is no comparable national program to develop such resources. There is a significant undeveloped potential for developing high-enthalpy geothermal systems in the western USA, Hawaii and Alaska.