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U.S. DOE testimony on geothermal energy in front of Senate Energy Committee

U.S. DOE testimony on geothermal energy in front of Senate Energy Committee Stillwater geothermal power plant of Enel, Nevada, (source: nbmg.unr.edu)
Alexander Richter 30 Jul 2011

In a Senate Committee testimony, the DOE quotes two key obstacles, the high cost and risk of exploration and most of identified hydrothermal resources already having been developed, as well as delay in sitting and permitting processes increasing project cost and time of development.

In a recent statement by Steven G. Chalk, Assistant Secretary, Renewable Energy Office of Energy Efficiency and Renewable Energy at the U.S. Department of Energy (DOE) in front of the Committee on Senate Energy and Natural Resources, he gave an overview on the renewable energy programs and activities of DOE.

Among the technologies he talked about he gave the following testimony on geothermal energy.

“The Department is committed to developing and deploying a portfolio of innovative technologies for clean, domestic geothermal power generation. Geothermal energy is a baseload energy resource with a small environmental footprint and emits little to no greenhouse gases. Despite geothermal’s enormous potential, in 2010, only 15 MW of new geothermal power generation was added to the grid in the United States. There are two principal barriers facing the geothermal industry: the high cost and risk of exploration and most of the identified hydrothermal resources have already been developed.

Drilling costs represent approximately 42 percent of geothermal project development costs, and financing costs are significantly higher for exploratory drilling than for plant construction. Removing the obstacles to exploratory drilling is vitally important to increasing our geothermal power generation capacity. In many cases, geothermal resources have no surface expression, leaving our nation’s hydrothermal potential – estimated at 30 GWe by the U.S. Geological Survey – untapped and inaccessible. Exploratory drilling could also identify resources for enhanced geothermal systems (EGS), which have the potential to produce 16,000 GWe of power in a wide range of geographic areas throughout the U.S.

Under the American Recovery and Reinvestment Act of 2009 (Recovery Act), DOE invested $97.3 million in 24 hydrothermal exploration projects, at which 34 exploration wells are planned. It is expected that from these wells, 400 MW of new resources will be confirmed by 2014. DOE is also funding seven EGS demonstrations. At Desert Peak, Nevada, the initial stages of reservoir stimulation were successfully completed- a critical milestone in creating an enhanced geothermal reservoir.

DOE supports projects in low temperature geothermal resources as well. For example, DOE is working with industry to develop and field test a variable phase turbine which has the potential to generate 30 percent more power from low temperature geothermal resources than current power conversion technologies, at a lower cost.

DOE’s National Geothermal Data System (NGDS) effort is a distributed information system for data sharing in its second year of development, which will enable the availability of comprehensive and accurate data to facilitate geothermal development. The NGDS is scheduled to be fully operational in August 2014, at which time it will make geothermal data from major geothermal centers, DOE-funded geothermal projects and state geological surveys or universities publicly available.

DOE currently has projects in many of the areas identified for further RD&D and commercial application in S. 1142, including district heating and cooling at large institutions, use of hot water in shaft mines, combined GHP-solar PV and desiccant projects, and use of carbon dioxide as a refrigerant fluid for heat exchange.

The Department is also addressing other obstacles to geothermal development such as delays in the siting and permitting process which increase overall project costs and could further strain economics. Currently, it takes approximately seven years for a new geothermal project to move from exploration to power generation.

While the Administration is still reviewing the bill, there are serious technical concerns that would need to be addressed. Any new program should be consistent with applicable laws, and structured to mitigate risks and costs to the taxpayer.”

Source: Cogeneration & On-Site Power Production