American Association of State Geologists-National Geothermal Data System State Geothermal Data Program: Ohio Geological Survey Fiscal Years 2010-2013 Final Technical Report for Delivery of Geothermal Relevant Data and Metadata from the Extensive Collections of the Ohio Division of Geological Survey and Other Published and Unpublished Sources Ohio Contribution to the National Geothermal Data System Grant OH-EE0002850 Budget period: 07/01/2010 through 10/31/2013 Timothy E. Leftwich-Principal investigator Ohio Department of Natural Resources-Division of Geological Survey Horace R. Collins Laboratory 3307 South Old State Rd. Delaware, OH 43015 740-548-5979 740-657-1979 (FAX) [email protected] Submitted November 30, 2013 1 ABSTRACT The State Geothermal Data project, organized by the Association of American State Geologists (AASG) with funding from the Department of Energy, brings data from all 50 States into the National Geothermal Data System (NGDS). The Ohio Geological Survey (Survey) supplied numerous temperature, geochemistry, well logs, maps, GIS files, and other legacy geothermal-relevant data and published and unpublished existing digital and other data to the AASG data portal and the NGDS. A new content model for reporting physical and thermal properties data for abandoned underground mines was created by the Survey with help from partners at Ohio University, Athens Ohio. New heat flow values were also estimated for the Burger Well (FEGENCO #1) in eastern Ohio. In total, more than fifty maps, documents, files, and other datasets were delivered to AASG for exposure to the NGDS. This final project report lists the general accomplishments of this project and also lists conference presentations and proceedings completed under the project. INTRODUCTION Geysers, hot springs, and volcanoes are not the only sources of geothermal energy, which is defined as “heat from the earth”. Even in Ohio, temperatures increase with depth below the surface in a near-linear fashion called the geothermal gradient. For example, a visitor to a typical Ohio cave will experience a temperature of roughly 55 degrees Fahrenheit (°F) at a depth of about 100 feet, whereas the temperature that a miner labors in at a depth of approximately 2,000 feet in an underground salt mine in northern Ohio is nearly 80 °F. Temperatures measured in oil and gas wells greater than 8,000 feet deep in eastern Ohio, on the other hand, may exceed 160 °F. Geothermal energy is considered a renewable resource because heat is continually flowing to the surface from Earth’s super-hot interior, thus maintaining Earth’s subsurface temperatures. Geothermal energy can thereby be used directly for electricity production where temperatures are very high, for space heating, or simply in shallow geothermal heat pump (GHP) systems to control building temperatures—both heating and cooling. The focus of geothermal energy research is most often on high-temperature, or high- enthalpy, geothermal electricity production, particularly in areas of recent tectonic activity with warm near-surface temperatures such as the western U.S. Indeed, high-enthalpy geothermal electricity production may someday be possible by tapping heat produced in Ohio’s relatively shallow granitic basement rocks (e.g., Tester et al., 2007; Batir et al., 2010). However, there are other geothermal resources in Ohio that could be exploited by GHP technology as well as by new emerging technologies. Efficient, low-cost geothermal systems have the potential to become an important part of Ohio’s energy repertoire. In particular, the emerging technology of using flooded abandoned underground mines (AUMs) as geothermal water sources represents a tremendous untapped energy source (e.g., Banks et al., 2004). 2 Geothermal heat pump systems typically use about half the energy needed for heating and cooling with traditional systems (e.g., Lund et al., 2005a, 2005b; Watzlaf and Ackman, 2006). Commercial/public GHP installations are taking off for public schools, universities, and hospitals in Ohio. Even though the growth in GHPs is strong in Ohio and in the U.S. in general, GHP systems still account for only about 0.5 percent of all heating, ventilating, and air conditioning (HVAC) sales in the U.S. (Lund et al., 2005b). In spite of strong growth in the GHP industry, the current state of understanding and acceptance of GHP technology by the U.S. public, as well as by its policy makers, is very limited and is perhaps the greatest inhibitor to the growth of this important energy-saving technology (Hughes, 2008). There are a number of important barriers to wider implementation of GHP technology. Understanding of GHP systems in the U.S. is often poor even for many individuals with technical or scientific backgrounds (e.g., Hughes, 2008). However, the geotechnical evaluations and high initial costs of GHP systems also are major barriers to their further development (e.g., Rafferty, 2001; Hughes, 2008). Geologic data analyzed and archived by the Survey, along with input and datasets from researchers at Ohio University, The Ohio State University, and other institutions are particularly valuable for cost-effective planning of low-temperature geothermal energy activities and to control potential geotechnical difficulties. Geologic and geographic data are critical for analyzing the installation, operating costs and economic, environmental, and social benefits resulting from GHP installation (Battocletti and Glasslev, 2012). According to a Geo-Heat Center study, the ground-source heat pump industry has historically failed to take full advantage of the existing public information sources available for site characterization (Rafferty, 2001). Virtually every state and province in North America maintains a website (or sites) dedicated to ground water and geology. The Survey, The Ohio Environmental Protection Agency, and the Ohio Division of Soil and Water offer a wealth of data useful in the characterization of site geology and hydrology. This geologic and geothermal data can help provide basic geologic reconnaissance for geotechnical evaluations needed for high- temperature or GHP installations, thus helping to lower initial costs. These maps and data may also help to recognize potential geotechnical problems arising from cavernous bedrock, landslide prone areas, lithologic variations effecting thermal conductivity, or other geologic factors. Ohio has a rich legacy in natural resource and mineral extraction, especially with regards to coal mining and processing and there are over 4500 abandoned underground mines in Ohio (Crowell 2008). As a result, there are numerous flooded and partially flooded abandoned coal mines—generally within Southeastern and Eastern Ohio—that are potential geothermal resources. 3 Whether a specific abandoned underground mine has geothermal potential is dependent on both the characteristics of the site, and the market for energy. Assessing the geothermal potential of individual mine sites requires detailed review of existing information about the mines and their physical properties. Our new AUM physical and thermal properties content model captures knows geothermal-relevant data for these important features. AASG was founded in 1908 and represents the State Geologists of the 50 United States and Puerto Rico in seeking to advance the science and practical application of geology and related earth sciences in the United States and its territories, commonwealths, and possessions. The State Geothermal Data project, organized by AASG with funding from the Department of Energy, brings geothermal relevant data from 47 of the 50 States into the National Geothermal Data System (NGDS). This project can help expose the thousands of databases, directories, and geologic maps from state geological surveys that constitute a national resource for geothermal research and applications. Ohio’s contributions to the AASG project and the presentations that resulted from these efforts are outlined briefly in the following sections. PROJECT GOALS ACCOMPLISHED Ohio First Year Deliverables Ohio Bottom-hole Temperatures for Ohio This dataset contains 334 bottom-hole temperatures and corrected temperatures from oil-and-gas wells in Ohio and well data. The temperature readings are recorded on oil- and gas-well geophysical logs. Ohio BHT data were converted to °C and corrected using the methods outlined in Harrison et al. (1989) and the Southern Methodist University (SMU) correction (Blackwell and Richards, 2004a, 2004b). The Harrison corrected values were used for BHT site location gradient values as input for the SMU correction. The SMU correction added or subtracted amounts from the Harrison corrected BHT value, according to each well's gradient. The formula was modified for low and moderate gradients because the resultant BHT values were too low. Hence, 5°C was added to wells with gradients of less than 20°C/km, 5° was subtracted from the BHTs with gradients of 20 - 27°C/km, 5°C was added for gradients of 27 - 30°C/km, and those over 30°C/km had a constant value of 11°C added to the temperature. The geothermal gradients were then recalculated. SMU calibrated temperature had errors of about 5 - 10% based on the direct comparison of the equilibrium temperature logs (Blackwell et al., 1994). However, these maps can readily be updated as new data and corrections become available. (Leftwich, T.E., Wolfe, M.E., and Wells, J.G., 2011, Bottom-hole temperatures for Ohio: Ohio Division of Geological Survey unpublished data.) Ohio Well Log Data