Geothermal Energy pt. 1 Flashcards
“Energy is the only universal currency”
- Vaclav Smil
___ means “earth,” and ____ means “heat” in Greek.
geo
thermal
_____ is heat that flows continuously from the Earth’s interior to the surface and has been doing so for about 4.5 billion years.
The temperature at the center of the Earth is about the same as the surface of the sun (nearly 6,000°C, or about 10,800°F).
Geothermal energy
Why Is Geothermal Energy A Renewable Source?
This heat is continually replenished by the decay of naturally occurring radioactive elements beneath the subsurface and will remain available for ____, ensuring an essentially inexhaustible supply of energy.
billions of years
Island ocean trenches, volcanoes, and mid-ocean ridges are all formed by the _____ of molten material between the Earth’s mantle and crust
movement
Earth Gets Hotter the ____ You Go
Internal heat production: 20TW
Measured heat flow Qs = 44TW
Deeper
Earth cools down ____ quicker than heat production, however the heat content of the Earth would take over 10 (billion) years to exhaust via global terrestrial heat flow (practically inexhaustible on human-scale)
2X quicker
Why is the inside of the Earth hot?
The _____ left over from the collisions of large and small particles that created Earth in the first place.
The other source is radioactivity, specifically the spontaneous radioactive decay of the isotopes ^ 235 U, ^ 238 U ^ 40 K, and 232Th which are primarily present in the mantle.
frictional heat
Geothermal Features
- _____ - jets of water and steam
- _____
- _____ - vents or openings at the surface where volcanic gases and vapors are emitted.
- ______ form when limited amounts of geothermal water mix with mud and clay
Geysers
Hotsprings
Fumaroles
Mudpots
GEOTHERMAL ENERGY: BASIC CONCEPTS
_____ (GSHPs) are the primary method for direct use of geothermal energy.
The United States generates the most geothermal electricity in the world-more than 3.7 gigawatts. That’s enough to power about 2.7 million U.S. homes.
The______ near Newcastle, Utah, is one of the dozens of greenhouses in the USA that benefit from its direct use of geothermal energy.
Geothermal (or ground source) heat pumps
Milgro Nursery Greenhouse
GEOTHERMAL ENERGY: BASIC CONCEPTS
Geothermal energy has two primary applications: ______ and _____ generation.
The U.S., Indonesia, Philippines, Turkey, New Zealand, and Mexico had 75% of global installed geothermal power capacity in 2021
The largest geothermal plant in the world is located in north San Francisco California: The ________ is comprised of 18 power plants.
______ Geothermal Power Plant is a 458-MW geothermal power station complex in Laguna and Quezon
heating/cooling and electricity generation
Geysers Geothermal Complex
Makiling-Banahaw (Mak-Ban) Geothermal Power Plant
GEOTHERMAL ENERGY: BASIC CONCEPTS
__ invents the first geothermal power plant at the Larderello dry steam field in Tuscany, Italy in 1904.
_____ from that geothermal source was used to turn a small turbine which powered five light bulbs.
The _____ geothermal power plant in Tuscany is the oldest dry steam power plant in the world
Prince Piero Ginori Conti
Steam
Larderello geothermal power plant
GEOTHERMAL ENERGY: BASIC CONCEPTS
The most active geothermal resources are usually found along major tectonic plate boundaries where most volcanoes are located.
One of the most active geothermal areas in the world is called the _____, which encircles the Pacific Ocean.
Ring of Fire
Three Methods for Geothermal Energy Capture (Heat Mining)
- ____
- Liquid and superheated water
- Vapor and dry steam - _____
- hot dry rocks (HDR) or Enhance Geothermal Systems (EGS) - Geothermal heat pumps (GHP)
Hydrothermal
Deep geothermal systems-
Three Methods for Geothermal Energy Capture (Heat Mining)
- _____
Considered conventional geothermal resources (they can be developed using existing technologies and do not require creation of human-made reservoirs as needed)
Steam or hot water occur naturally
When temperature of a hydrothermal resource is around ____ (105 °C) and up, it can be used to generate electricity
Hydrothermal
220F
Three Methods for Geothermal Energy Capture (Heat Mining)
- _____
Much more abundant than hydrothermal regions: temperatures of 200 °C
______ , created artificially by hydraulically fracturing a deep well drilled into hot, impermeable, crystalline basement rock.
Deep wells for production and injection of water.
Deep wells for production and injection of water.
same answer
Hot dry rock
Hot dry rock reservoirs
Economics of Geothermal Energy
The Hot Dry Rock (HDR) resource is much larger and more widespread than hydrothermal resources.
The minimum cost for HDR will likely occur later than that for hydrothermal (see Figure), and at some point the curves will probably intersect, meaning it will become less expensive to develop HDR resources than the remaining low quality hydrothermal resources.
basa
Requires significant amount of start-up capital, but the overall capital cost and operating costs of geothermal power are significantly lower than many other technologies.
Geothermal plants have no fuel cost, and minimal maintenance.
If geothermal power is so economical why are there not projects generating power across the world?
* High upfront cost
* Risk of exploratory drilling
* Uneven policies and subsidies
basa
The Three Laws of Geothermal Economics
- 1st Law-Completed well cost increase _____ with depth
- 2nd Law-Power plant cost decrease ____ with temperature
- 3rd Law - As resource quality ________ drilling cost dominate
exponentially
linearly
decrease
Geothermal energy provides electricity generation in more than ____ countries.
Countries belonging to the geothermal “1 GWe club” (Indonesia, New Zealand, Philippines, Türkiye and the United States) - geothermal plants have been operating for decades.
20 countries
The Nesjavellir Power Plant is one of six geothermal power plants in Iceland. Nesjavellir provides eleciricity to Iceland’s capital, Reykjavik.
The global installed capacity for geothermal generation of electricity was 15.96 GWe at the end of 2021, distributed across five main regions.
The regions with the largest installed capacity are ____, ____ and ____
Asia and Oceania
North America
Eurasia
SUPPLY AND SOURCES (INTERNATIONAL)
Global geothermal power generation potential is between 70 to 80 gigawatts (GW).
Just _____ of known geothermal reserves around the world are exploited for electricity production, generating just 13 GW.
15%
SUPPLY AND SOURCES (INTERNATIONAL)
_____ take advantage of natural underground sources of steam. The steam is piped directly to a power plant, where it is used to fuel turbines and generate electricity.
The United States has only one dry-steam power plant, The ____ in California
Dry-steam power plants
Geysers
SUPPLY AND SOURCES (LOCAL)
The Philippines being located in the Pacific “ring of fire” is abundant of geothermal resource potential.
Geothermal exploration was started in 1962, and the first large commercial power plants came on line in _____.
The Philippine Government aims to increase its renewable energy capacity to an estimated 15,304 MW by 2030 comprising of 1495 MW for geothermal capacity.
1979
