WWW.THESIS.XLIBX.INFO
FREE ELECTRONIC LIBRARY - Thesis, documentation, books
 
<< HOME
CONTACTS



Pages:   || 2 | 3 | 4 | 5 |   ...   | 8 |

«Nikhil Manikonda Faculty of Graduate and Postdoctoral Studies Department of Civil Engineering University of Ottawa Ontario, Canada. ©Nikhil ...»

-- [ Page 1 ] --

PERFORMANCE OF DEEP GEOTHERMAL

ENERGY SYSTEMS

Dissertation submitted in partial fulfillment for the award of the

degree of Master of Applied Sciences

In

Environmental Engineering

By

Nikhil Manikonda

Faculty of Graduate and Postdoctoral Studies

Department of Civil Engineering

University of Ottawa

Ontario, Canada.

©Nikhil Manikonda, Ottawa, Canada, 2012.

ACKNOWLEDGEMENTS

First and foremost, I offer my obeisance to the Almighty for having bestowed his grace. I humbly present this research as a part of my curriculum, which contains the details of research work on the “Performance of deep geothermal energy systems”.

I sincerely wish to acknowledge and thank my supervisor Dr. Majid Mohammadian for his deep sincerity, support, and guidance throughout the research work, whose kind cooperation helped me collect sufficient information for the completion of this work I am very thankful to all my friends and family members for their support and encouragement during the dissertation. Most importantly, I thank my girlfriend for pushing me forward and reminding me that I was capable of doing it, even when I was down.

Nikhil Manikonda i Abstract Geothermal energy is an important source of clean and renewable energy. This project deals with the study of deep geothermal power plants for the generation of electricity. The design involves the extraction of heat from the Earth and its conversion into electricity.

This is performed by allowing fluid deep into the Earth where it gets heated due to the surrounding rock. The fluid gets vaporized and returns to the surface in a heat pipe. Finally, the energy of the fluid is converted into electricity using turbine or organic rankine cycle (ORC). The main feature of the system is the employment of side channels to increase the amount of thermal energy extracted. A finite difference computer model is developed to solve the heat transport equation. The numerical model was employed to evaluate the performance of the design. The major goal was to optimize the output power as a function of parameters such as thermal diffusivity of the rock, depth of the main well, number and length of lateral channels. The sustainable lifetime of the system for a target output power of 2 MW has been calculated for deep geothermal systems with drilling depths of 8000 and 10000 meters, and a financial analysis has been performed to evaluate the economic feasibility of the system for a practical range of geothermal parameters. Results show promising an outlook for deep geothermal systems for practical applications.

ii Table of Contents Overview:

Objectives of the present study

Methodology

Structure of thesis

Chapter 1: Introduction

1.1 Working pattern of geothermal power plant

1.2 Closed loop versus open loop geothermal systems

1.2.1. Closed loop systems

1.2.2. Open loop systems

1.3. Geothermal power plant types

1.3.1 Dry steam power plant

1.3.2 Flash steam power plant

1.3.3 Binary steam power plant

1.3.4 Hybrid power plant

1.4. Different uses geothermal energy

1.5. Drilling technologies

1.5.1 Diamond drilling

1.5.2. Rotary steerable PDC drill

Chapter 2: Literature review

2.1. Deep geothermal power plants

2.1.1. Geothermal electricity generation in Soultz-sous Forets

2.2 Shallow geothermal systems:

Chapter 3: A modified design for deep geothermal systems and numerical modeling.......... 53

3.1. Governing equation

3.2. Numerical scheme

3.3. Calculation of the source term

3.4. Computer program

3.5. Computational grid and boundary conditions

iii 3.6. Typical output power

4.1. Budgeting

4.2. Need for budgeting

4.3. Budgeting for the geothermal power plant

4.4. Calculations for cost analysis

4.4.1. Total drilling length 8,000m

4.4.2. Total drilling length 10000m

Chapter 5: Sensitivity analysis and numerical results

5.1. Model Parameters

5.2. Sensitivity analysis

5.2.1. Sensitivity to the grid size

5.2.2. Sensitivity to the time step size

5.2.3. Sensitivity to the depth of main well

5.2.4. Sensitivity to the vertical distance between lateral channels

5.2.5. Sensitivity to the number and length of side channels:

5.3. Numerical results

5.3.1. Total drilling length of 10,000m

5.3.2. Total drilling length of 8,000 m

Chapter 6: Summary and Conclusions

7. References

Appendix I

I.1 System lifetime with respect to distance between side channels

Appendix II

II.1 Present value (P) analysis:

–  –  –

Figure1.1: First geothermal power plant in Italy [1]

Figure1.2: Plant view and working employees - 1st Geothermal Power Plant (1904) [1].

....... 4 Figure1.3: Closed loop system with power cycle [7]

Figure1.4: Typical heat pipe design [9]





Figure1.5: Open loop system [10]

Figure1.6: Dry steam geothermal power plant [13]

Figure1.7: Flash system power plant [15]

Figure1.8: Binary steam power plant cycle [17]

Figure1.9: Diamond cutter drill bit [21]

Figure1.10: Rotary steerable PDC drill sample [22]

Figure2.1: ORC system of a geothermal power plant [23]

Figure2.2: Temperature versus depth profile [24]

Figure2.3: Performance of the system at a depth of 5000m [24]

Figure2.4: Cross section temperature profile oriented to the main groundwater flow direction [25]

Figure2.5: A schematic view of a geothermal power plant U-pipe system [26]

Figure2.6: Geothermal power gain versus velocity of the system shown in Fig.

2.5 [26]........ 35 Figure2.7: Sketch of a deep BHE with varying pipe diameter [27]

Figure2.8: Cross section of a typical double-U shaped BHE [27]

Figure2.9: Temperature distribution around two running BHEs which are extracting heat [27]

Figure2.10: Sketch of double U-tube BHE cross-section [28]

Figure2.11: Temperature (0C) change versus time (months) [33]

Figure2.12: Temperature distribution and BHE workloads for non-optimized equal load [33]

Figure2.13: Schematic diagram of boreholes in GHE.

(a) Double U-tube and (b) Single Utube [35]

Figure2.14: Borehole thermal resistance versus thermal conductivity [35]

Figure2.15: Function for four interacting boreholes separated by a distance B [37].

............... 47 Figure2.16: 3D image of the resulting mesh [39]

Figure2.17: Temperature contours after 5, 10, 20, and 30 years [42]

Figure 2.18: 3-D finite element model top view [43]

Figure3.1: Flowchart showing the system model

Figure3.2: X-Y view of a mesh

Figure3.3: Typical simulation result where colours show the temperature difference.

Heat pipes are identified by the light blue colour.

v Figure3.4: Typical output power versus time (days)

Figure3.5: Demand curve performance

Figure3.6: Sinusoidal performance of the system-Tecplot image

Figure3.7: 2D image of the simulation using Tecplot

Figure4.1: Expected average power generation with respect to time (months)

Figure4.2: Total cost versus time (months) for a total drilling length of 8,000m

Figure4.3: Total cost versus time (months) for a total drilling length of 10,000m.

................. 77 Figure5.1: Depth of main well vs. time

Figure5.2: System lifetime with respect to the distance between channels for a geothermal gradient of 350C/km and a total drilling length of 10,000m

Figure5.3: System lifetime with respect to the distance between channels for a geothermal gradient of 450C/km and a total drilling length of 10000m.

Figure5.4: System lifetime with respect to the distance between channels for a geothermal gradient of 550C/km and a total drilling length of 10,000m

Figure5.5: System lifetime with respect to the distance between channels for a geothermal gradient of 650C/km and a total drilling length of 10,000m

Figure5.6: System lifetime with respect to the distance between channels for a geothermal gradient of 350C/km and a total drilling length of 8,000m

Figure5.7: System lifetime with respect to the distance between channels for a geothermal gradient of 450C/km and a total drilling length of 8000m

Figure5.8: System lifetime with respect to the distance between channels for a geothermal gradient of 550C/km and a total drilling length of 8,000m

Figure5.9: System lifetime with respect to the distance between channels for a geothermal gradient of 650C/km and a total drilling length of 8,000m

Figure6.1: Optimal lifetime with respect to thermal diffusivity for total drilling length of 8,000m for various geothermal gradients (shaded region shows the economically unfeasible area)

Figure6.2: Optimal lifetime with respect to thermal diffusivity for total drilling length of 10,000m for various geothermal gradients (shaded region shows the economically unfeasible area)

viList of Tables:

Table1.1: Drilling factors and their performances [21]

Table2.1: Results illustrating the performance of the system [24]

Table4.1: System components and their costs

Table 4.2: Cost analysis for a total drilling length of 8000m

Table4.3: Cost analysis for a total drilling length of 10000m

Table5.1: Range of Initial Parameters

Table5.2: Depth of main well

Table5.3: Length and number of channels used in optimization for total drilling length of 10,000 m

Table6.1: Optimal design conditions for geothermal gradient of 550C/Km

Table6.2: Optimal conditions and system lifetime for geothermal gradient of 350C/km (shaded region shows the economically unfeasible area)

Table6.3: Optimal conditions and system lifetime for geothermal gradient of 450C/km (shaded region shows the economically unfeasible area)

Table6.4: Optimal conditions and system lifetime for geothermal gradient of 550C/km (shaded region shows the economically unfeasible area)

Table6.5: Optimal conditions and system lifetime for geothermal gradient of 650C/km (shaded region shows the economically unfeasible area)

Table I.1: System lifetime with respect to distance between side channels for total drilling length of 10000(m) and geothermal gradient of 350C/km (shaded region shows the economically unfeasible area)

Table I.2: System lifetime with respect to distance between side channels for total drilling length of 8000(m) and geothermal gradient of 350C/km (shaded region shows the economically unfeasible area)

Table I.3: System lifetime with respect to distance between side channels for total drilling length of 10000(m) and geothermal gradient of 450C/km (shaded region shows the economically unfeasible area)

Table I.4: System lifetime with respect to distance between side channels for total drilling length of 8000(m) and geothermal gradient of 450C/km (shaded region shows the economically unfeasible area)

Table I.5: System lifetime with respect to distance between side channels for total drilling length of 10000(m) and geothermal gradient of 550C/km (shaded region shows the economically unfeasible area)

Table I.6: System lifetime with respect to distance between side channels for total drilling length of 8000(m) and geothermal gradient of 550C/km (shaded region shows the economically unfeasible area)

vii Table I.7: System lifetime with respect to distance between side channels for total drilling length of 10000(m) and geothermal gradient of 650C/km (shaded region shows the economically unfeasible area)

Table I.8: System lifetime with respect to distance between side channels for total drilling length of 8000(m) and geothermal gradient of 650C/km (shaded region shows the economically unfeasible area)

–  –  –

BHE: Borehole heat exchanger EGS- Enhanced geothermal system FD- Finite difference FE- Finite element GCHP- Ground coupled heat pump GHE- Ground heat exchanger GHP- Geothermal heat pump GSHP: Ground source heat pump HDR- Hot dry rock ORC- Organic rankine cycle PDC- Polycrystalline diamond compact TRCM- Thermal resistance and capacity models UGCHE- U vertical ground coupled heat exchanger

–  –  –

T = Fluid temperature in the in-pipe u = refrigerant fluid velocity ɸ = specific heat transfer co-efficient z = vertical coordinate Ts = vertical soil temperature D = depth t = time step size T = temperature Ti,nj,k = temperature at time t  nt at the location represented by the gird point (i, j,k) Ti,nj,1 = temperature at time t   n  1 t at the location represented by the gird point (i, j,k) k K x, K y and K z = respectively the thermal diffusion coefficient in x, y, and z directions t = the time S = the heat source or sink v  x  y  z = volume of the computational cell

–  –  –

Objectives of the present study

The following objectives are considered in this study:

 To design a geothermal power plant that can generate 2 MW of electricity and

–  –  –

 To estimate system lifetime under various conditions using numerical simulations.

 To obtain the optimal conditions which lead to maximum system life time.

 To conduct a financial analysis in order to make sure that the system is economical.

Methodology A numerical approach has been employed in this project to design an economical geothermal power plant system. Initially, an imaginary geothermal power plant design is prepared. All the parameters that feature in order to develop the power plant are considered and a numerical model is developed. The equations are solved with the help of the computer program written in FORTRAN. The grid independency and time step independency analysis are also performed.



Pages:   || 2 | 3 | 4 | 5 |   ...   | 8 |


Similar works:

«Gnu Scientific Library Have your workers Gnu Scientific Library and tangible magazines used provided normally? The 12-month one they find in the receptionist, and these excess five tell up the security, then to demand emailed. A most caps think Federal Center when 4 audience of deadlines are that thing but activities from BASE when interview of goods have ideal ability. What agendas Gnu Scientific Library have you are a and let to purchase applied, evicted, and be so how you feel? When the...»

«DIVISION OF INSTRUCTIONAL TECHNOLOGY FISCAL YEAR 2013-2014 ANNUAL REPORT Table of Contents Executive Director Welcome Introduction Division Overview Organizational Chart Division Accomplishments Classroom and Lab Technologies Learning Support Services Educational Media Services Communication and Planning DoIT Operations Accolades and Scholarship Advanced Certifications Awards and Honors Councils and Committees Presentations Publications Teaching –  –  – For the Division of...»

«PÉCSI TUDOMÁNYEGYETEM KÖZGAZDASÁGTUDOMÁNYI KAR GAZDÁLKODÁSTANI DOKTORI ISKOLA Kiss Viktor Miklós THE ENERGY SYSTEM OF PÉCS – A SIMULATION MODEL DOKTORI ÉRTEKEZÉS TÉZISEI Témavezető: dr. Bugár Gyöngyi Pécs,02015 Contents Executive Summary Importance of energy management Research goal Boundaries of the research Build-up of the dissertation Hypotheses of the dissertation Main results Published articles and conference participations References Executive Summary The global demand...»

«Xiangmin (Jim) Jiao, Ph.D. Department of Applied Mathematics & Statistics Phone: (631) 632-4408 Fax: (631) 380-8004 State University of New York at Stony Brook Email: xiangmin.jiao@stonybrook.edu Stony Brook, NY 11794-3600 URL: http://www.ams.sunysb.edu/~jiao RESEARCH INTERESTS Numerical and geometric computing in science and engineering, including numerical methods, applied computational geometry and topology, high-performance computing, and geometric data analysis. Specialize in tracking...»

«Desktop Originator/Desktop Underwriter Release Notes DU Version 10.0 February 23, 2016 Last Updated June 20, 2016 During the weekend of September 24, 2016, Fannie Mae will implement Desktop Underwriter® (DU®) Version 10.0, which will include the changes described below. To support our lending partners, Fannie Mae continues to make ongoing investments in our risk management tools, enabling greater confidence and efficiency in the origination process. These tools help to provide the highest...»

«Working Papers of the Cornell Phonetics Laboratory 2003, v.15, pp. 101-129 Diminutive Reduplication in Modern Hebrew* Rina Kreitman In this paper I explore diminutive reduplication in Modern Hebrew (MH) using an Optimality Theoretic (McCarthy & Prince 1995) framework, which has the advantage of allowing interaction of phonological and morphological constraints regulating the reduplication process. I claim that reduplication in MH stems from general principles of reduplication interacting with...»

«THOMSON REUTERS STREETEVENTS EDITED TRANSCRIPT NFLX Q4 2015 Netflix Inc Earnings Call EVENT DATE/TIME: JANUARY 19, 2016 / 10:00PM GMT THOMSON REUTERS STREETEVENTS | www.streetevents.com | Contact Us ©2016 Thomson Reuters. All rights reserved. Republication or redistribution of Thomson Reuters content, including by framing or similar means, is prohibited without the prior written consent of Thomson Reuters. 'Thomson Reuters' and the Thomson Reuters logo are registered trademarks of Thomson...»

«8th Annual CUSRR Colby Undergraduate Summer Research Retreat July 23-24, 2015 Crab Apple Whitewater, The Forks, ME Kevin P. Rice, Ph.D. Associate Professor of Chemistry, Colby College 5763 Mayflower Hill Road Waterville, ME 04901 (207) 859-5763; kevin.rice@colby.edu July 23, 2015 To the participants of the 8th annual Colby Undergraduate Summer Research Retreat: With 98 student presenters and over 150 total participants, CUSRR 2015 will be the largest event yet! We are particularly grateful to...»

«Enterprise Research Service Research Brief Elevating Customer Analytics Initiatives and Building the Coveted Holistic Customer View November 2014 Written By: Christy Maver, Actian iianalytics.com Copyright©2014 International Institute for Analytics. Proprietary to subscribers. IIA research is intended for IIA members only and should not be distributed without permission from IIA. All inquiries should be directed to membership@iianalytics.com. Enterprise Research Service Key Takeaways 1. The...»

«Geography Supplementary Postgraduate Research Student Handbook 2012/3 Contents About this handbook Local contacts Access to the Building Postgraduate Workspace Computers Printers Support for Conferences and Fieldwork Inter-Library Loans Equipment Vehicles Technical Services Seminars Reading Groups Annual monitoring Upgrade (End of Year One) Procedures Referencing About this handbook This is a supplementary handbook for postgraduate research students in Geography. If your lead supervisor is a...»

«CITY OF CENTRAL POINT City Council Meeting Minutes July 16, 2015 REGULAR MEETING CALLED TO ORDER Council President Bruce Dingier called the meeting to order at 7: 00 p. m. PLEDGE OF ALLEGIANCE II. ROLL CALL: Mayor: Hank Williams, excused III. Council Members. Bruce Dingier, Brandon Thueson, Taneea Browning, Rick Samuelson, and Mike Quilty were present. Allen Broderick, excused. City Manager Chris Clayton; City Attorney Sydnee Dreyer; Police Chief Kris Allison; Community Development Director Tom...»

«A Practical Guide for Newcomers Entering the Canadian Labour Market About the Author Since coming to Canada more than 10 years ago, Nick Noorani has dedicated himself to helping other newcomers in Canada succeed. He started his journey by co-writing the book Arrival Survival Canada, a handbook to help immigrants in their first few years in Canada. He also founded Canadian Immigrant magazine, which kicked off his career as a motivational speaker. After years of research and one-on-one...»





 
<<  HOME   |    CONTACTS
2016 www.thesis.xlibx.info - Thesis, documentation, books

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.