Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature...
Transcript of Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature...
![Page 1: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/1.jpg)
Geothermal Energy
![Page 2: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/2.jpg)
Learning objectives:
1)To describe the principle behind tapping of Geothermal energy
2)To indicate limits and challenges with Geothermal energy usage
![Page 3: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/3.jpg)
Crust 30
Upper Mantle 720
Lower Mantle 2170
Outer Core 2260
Inner Core 1220
Thickness
(km)
Cross-section of the Earth
Core: Iron, Nickel, noble metals
Mantle: Sulphide and Oxide rich
Crust: Oxides
![Page 4: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/4.jpg)
Crust 30
Upper Mantle 750
Lower Mantle 2920
Outer Core 5180
Inner Core 6400
Depth
(km)
Cross-section of the Earth
Core: Iron, Nickel, noble metals
Mantle: Sulphide and Oxide rich
Crust: Oxides
![Page 5: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/5.jpg)
Crust 0-700
Upper Mantle 1000
Lower Mantle 3500
Outer Core 4000
Inner Core 7000
Temperature
(oC)
Cross-section of the Earth
Core: Iron, Nickel, noble metals
Mantle: Sulphide and Oxide rich
Crust: Oxides
![Page 6: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/6.jpg)
Deepest spot in the oceans:
The Challenger Deep / Mariana’s Trench: 11 Km deep
(In the Pacific Ocean, near Japan)
Deeper than the height of Mt Everest 8.9 Km
Deepest spot in the lands:
Drill hole in Soviet peninsula of Kola: 12 Km deep
![Page 7: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/7.jpg)
Composition of Earth determined from:
1) Flow of heat from inside earth
2) Experiments on surface minerals and rocks under high P, T
3) Gravity and magnetic fields of earth
4) Path of earth quake waves travelling through the earth
![Page 8: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/8.jpg)
Principle of Geothermal energy usage:
Temperature gradient is of the order of 25 oC to 30 oC per km
20 oC per km in northern latitudes 40 oC per km closer to equator
![Page 9: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/9.jpg)
Principle of Geothermal energy usage:
Temperature gradient is of the order of 25 oC to 30 oC per km
Common usage 150 m to 200 m with temperature increase of less than 10 oC
Oil industry drills 5,000 to 10,000 m, temperature greater than 350 oC. Electronics will struggle
Faults will enable access to higher temperatures
![Page 10: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/10.jpg)
Principle of Geothermal energy usage:
Deep Water Horizon (US, Transocean, 2010): 10.5 km deep
Sakahlin-1 (Russia, Exxon, 2012): 12.3 km deep
![Page 11: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/11.jpg)
Principle of Geothermal energy usage:
Anticipated lifetime: approximately 30 years
![Page 12: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/12.jpg)
Conclusions:
1) Geothermal energy preferably tapped near faults
2) Deep drills already being made for oil industry
![Page 13: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/13.jpg)
Geothermal EnergyTechnological aspects
![Page 14: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/14.jpg)
Learning objectives:
1)To describe the different conditions relevant to Geothermal energy availability
2)To describe variations in Geothermal plant design
![Page 15: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/15.jpg)
Crust 0-700
Upper Mantle 1000
Lower Mantle 3500
Outer Core 4000
Inner Core 7000
Temperature
(oC)
Cross-section of the Earth
Core: Iron, Nickel, noble metals
Mantle: Sulphide and Oxide rich
Crust: Oxides
![Page 16: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/16.jpg)
Prospecting
To enable identification of better locations for plant
Temperature as a function of depth
Tattapani, Balrampur District, Chhattisgarh
![Page 17: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/17.jpg)
Prospecting
Helps identify low density regions for drilling
Nearly 40% of cost of geothermal energy associated with exploration
![Page 18: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/18.jpg)
Large plants
Geysers geothermal complex California (1500 MW)
Philippines (3); US, Indonesia (2); Mexico, Italy, Iceland (1)
![Page 19: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/19.jpg)
Super heated steam
Rare to find
Run a turbine. Should be corrosion resistant
Follow up with a condenser. Replenish the water
![Page 20: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/20.jpg)
Pro
du
ctio
n w
ell
Inje
ctio
n w
ell
Generator
![Page 21: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/21.jpg)
Pro
du
ctio
n w
ell
Inje
ctio
n w
ell
Generator
![Page 22: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/22.jpg)
Saturated steam
Found relatively more often
Cannot be used directly since it can damage the turbines
Heating? Pressure?
Flashing
![Page 23: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/23.jpg)
Pro
du
ctio
n w
ell
Inje
ctio
n w
ell
GeneratorFlash Tank
![Page 24: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/24.jpg)
Hot water
Found in many places
Binary fluid cycle: Butane (-1 oC), Isobutane (-11.7 oC) or Pentane (36.1 oC)
![Page 25: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/25.jpg)
Pro
du
ctio
n w
ell
Inje
ctio
n w
ell
GeneratorHeat
Exchanger
![Page 26: Geothermal Energy - Nptel · 2019-02-21 · Principle of Geothermal energy usage: Temperature gradient is of the order of 25 oC to 30 oC per km Common usage 150 m to 200 m with temperature](https://reader030.fdocuments.us/reader030/viewer/2022040403/5e8a37cabd9a2037f65fc40b/html5/thumbnails/26.jpg)
Conclusions:
1) Geothermal energy is available with differing levels of heat
2) Geothermal plants have to be designed to account for the different prevalant conditions