Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


Patel1166 Master's Thesis.pdf (2.82 MB)

ETD Abstract Container

Abstract Header

Optimal Heat Extraction for Geothermal Energy Applications

Patel, Iti Harshad
http://rave.ohiolink.edu/etdc/view?acc_num=osu1462460957

Abstract Details

2016, Master of Science, Ohio State University, Civil Engineering.
Sedimentary basins are emerging candidates for geothermal deployment due to their widespread presence in the subsurface, large storage capacity, and high temperatures. These geothermal systems rely on the temperature of the reservoir—and thus the temperature of the extraction fluid produced to the surface—but these temperatures can decrease if the rate at which heat is extracted from the reservoir exceeds the rate at which the natural geothermal heat flux increases the temperature. In this context, sustainability is often synonymous with extracting heat at a rate that maintains the temperature of the production fluid at a desired level. This perspective of sustainability focuses on the physical/environmental performance of the geothermal reservoir. But preserving heat in the reservoir may not be economically viable. Environmental and economic performance are interconnected, and systems must consider both of these metrics when determining an optimal operation strategy to conserve both the longevity of the resource and the associated economic profit. Natural resource economics focuses on developing strategies for resource management and/or allocation that weighs the environmental and economic benefits of a system. The following thesis presents a natural resource economics model for the optimal management of a geothermal resource using conventionally used water or carbon dioxide (CO2) as a heat extraction fluid. I investigated the performance of a sedimentary basin geothermal resource under a variety of scenarios, parameterized those results to accurately predict change in geothermal performance, and implemented those results in a natural resource economic model. The Non-isothermal Unsaturated- saturated Flow and Transport (NUFT) code simulates a sedimentary basin geothermal reservoir under a range of geologic conditions and was used to understand and parameterize geothermal performance. I combined the simulation outputs from all the scenarios by normalizing the production temperature and energy that is extracted to create a reduced form representation of this relationship. This reduced form serves as an input into the natural resource economic model that uses Microsoft Excel’s Optimization Solver to determine the optimal mass flowrate time path to extract heat given the profit that can be made and the natural rate at which the reservoir temperature renews. The reservoir simulation results show that the relationship between normalized temperature of the produced fluid and normalized energy that is extracted is the Richard’s curve (i.e. a generalized logistic curve). The regeneration rate of the reservoir, the rate at which temperature renews within a reservoir, is considerably smaller than the rate of economic growth. As such, results from the natural resource economic model suggest it is often optimal to drawdown the temperature of the reservoir to gain the quickest payback of investment.
Jeffrey Bielicki (Advisor)
Ethan Kubatko (Committee Member)
Gopalakrishnan Sathya (Committee Member)
104 p.
Environmental Engineering
geothermal; natural resource economics; reservoir modeling; sedimentary basin; optimal

Recommended Citations

Citations

  • Patel, I. H. (2016). Optimal Heat Extraction for Geothermal Energy Applications [Master's thesis, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462460957

    APA Style (7th edition)

  • Patel, Iti. Optimal Heat Extraction for Geothermal Energy Applications. 2016. Ohio State University, Master's thesis. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1462460957.

    MLA Style (8th edition)

  • Patel, Iti. "Optimal Heat Extraction for Geothermal Energy Applications." Master's thesis, Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462460957

    Chicago Manual of Style (17th edition)

osu1462460957
1,978
© 2016, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.
Release 3.2.12