Using Geothermal Play Types as an Analogue for Estimating Potential Resource Size

Conference · Wed Sep 02 00:00:00 EDT 2015

OSTI ID:1253704

Terry, Rachel; Young, Katherine

Blind geothermal systems are becoming increasingly common as more geothermal fields are developed. Geothermal development is known to have high risk in the early stages of a project development because reservoir characteristics are relatively unknown until wells are drilled. Play types (or occurrence models) categorize potential geothermal fields into groups based on geologic characteristics. To aid in lowering exploration risk, these groups' reservoir characteristics can be used as analogues in new site exploration. The play type schemes used in this paper were Moeck and Beardsmore play types (Moeck et al. 2014) and Brophy occurrence models (Brophy et al. 2011). Operating geothermal fields throughout the world were classified based on their associated play type, and then reservoir characteristics data were catalogued. The distributions of these characteristics were plotted in histograms to develop probability density functions for each individual characteristic. The probability density functions can be used as input analogues in Monte Carlo estimations of resource potential for similar play types in early exploration phases. A spreadsheet model was created to estimate resource potential in undeveloped fields. The user can choose to input their own values for each reservoir characteristic or choose to use the probability distribution functions provided from the selected play type. This paper also addresses the United States Geological Survey's 1978 and 2008 assessment of geothermal resources by comparing their estimated values to reported values from post-site development. Information from the collected data was used in the comparison for thirty developed sites in the United States. No significant trends or suggestions for methodologies could be made by the comparison.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 1253704
• Report Number(s): NREL/CP-6A20-66437
• Resource Relation: Conference: Presented at the Geothermal Resources Council 2015 Annual Meeting, 20-23 September 2015, Reno, Nevada; Related Information: Geothermal: Always On; Proceedings of the Geothermal Resources Council 2015 Annual Meeting, 20-23 September 2015, Reno, Nevada
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
geothermal occurrence models
play types
geothermal
risk
resource potential
geology
exploration
resource size
temperature
volume
Monte Carlo
heat in place
USGS
resource assessment
probability distribution
recoverable heat
electric potential
OpenEI
reservoir characteristics
parameters