What are the Disadvantages of Geothermal Energy?
- Environmental Concerns about Greenhouse Emissions.
- Possibility of Depletion of Geothermal Sources.
- High Investment Costs for Geothermal System.
- Land Requirements for Geothermal System to Be Installed.
There are three types of geothermal power plants: dry steam, flash, and binary. Dry steam, the oldest geothermal technology, takes steam out of fractures in the ground and uses it to directly drive a turbine. Flash plants pull deep, high-pressure hot water into cooler, low-pressure water.
The steam rotates a turbine that activates a generator, which produces electricity. There are three types of geothermal power plants: dry steam, flash steam, and binary cycle.
A Geyser is an example of Geothermal energy. Hot springs, lava, and fumaroles are natural examples of geothermal energy. Geothermal power is currently more common in homes and businesses, using geothermal heat pumps to control the temperature in the building.
Which kind geothermal plant is most common type? Explanation: Flash Steam Power Plants are the most common form of geothermal power plant. The hot water is pumped under great pressure to the surface.
Geothermal energy is derived from the Earth's natural heat, which increases with depth. It has two main applications: heat production (via heat pumps or by direct heat exchange), power production (via steam turbines).
Enhanced geothermal systems, which require energy to drill and pump water into hot rock reservoirs, have life-cycle global warming emission of approximately 0.2 pounds of carbon dioxide equivalent per kilowatt-hour [11].
Hot water near the earth's surface is piped into buildings for heat. A district heating system provides heat for most of the buildings in Reykjavik, Iceland. Industrial applications of geothermal energy include food dehydration (drying), gold mining, and milk pasteurizing.
The flash steam power plant is the most common geothermal power plant type globally and is more energy efficient than the dry steam model. Flash steam power plants operate on highly-pressurized reservoirs where the water typically exceeds 360°F.
Geothermal energy is heat within the earth. The word geothermal comes from the Greek words geo (earth) and therme (heat). Geothermal energy is a renewable energy source because heat is continuously produced inside the earth. People use geothermal heat for bathing, to heat buildings, and to generate electricity.
The conversion efficiency of geothermal power plants is lower than all thermal plants. Worldwide review of published data gave an average conversion efficiency of 12%.
An Overview of Geothermal Pros and Cons:
| Pros | Cons |
|---|
| This energy source is more environmentally friendly than conventional fuel sources. | The largest single disadvantage of geothermal energy is that it is location specific. |
| A source of renewable energy. | Gases are released into the atmosphere during digging. |
Geothermal energy can heat, cool, and generate electricity: Geothermal energy can be used in different ways depending on the resource and technology chosen—heating and cooling buildings through geothermal heat pumps, generating electricity through geothermal power plants, and heating structures through direct-use
Why is geothermal energy a renewable resource? Answer: Because its source is the almost unlimited amount of heat generated by the Earth's core. Even in geothermal areas dependent on a reservoir of hot water, the volume taken out can be reinjected, making it a sustainable energy source.
Geothermal Power Plants are CompactA power plant that can generate 1 gigawatt (1,000 megawatts) per hour of electricity would take up a good deal of space.
Geothermal systems are built to last a very long time. “The indoor components typically last about 25 years (compared with 15 years or less for a furnace or conventional AC unit) and more than 50 years for the ground loop,” The Family Handyman magazine reports.
Geothermal heating system price varies depending on the type of loop system, usually either vertical or horizontal. On average, a typical home of 2500 square feet, with a heating load of 60,000 BTU and a cooling load of 60,000 BTU will cost between $20,000 to $25,000 to install.
Geothermal electricity generation is currently used in 26 countries, while geothermal heating is in use in 70 countries.
Direct Dry Steam(Also eliminating the need to transport and store fuels!) This is the oldest type of geothermal power plant. It was first used at Lardarello in Italy in 1904. Steam technology is used today at The Geysers in northern California, the world's largest single source of geothermal electricity.
Geothermal plants can release small amounts of greenhouse gases such as hydrogen sulfide and carbon dioxide. Water that flows through underground reservoirs can pick up trace amounts of toxic elements such as arsenic, mercury, and selenium.
Geothermal Power Plants
- Hot water is pumped from deep underground through a well under high pressure.
- When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam.
- The steam spins a turbine, which is connected to a generator that produces electricity.
The disadvantages of geothermal energy are mainly high initial capital costs. The cost of drilling wells to the geothermal reservoir is quite expensive. Inefficient geothermal heat pumps might hike electricity bills. Geothermal sites may just run out of steam after years of activity.
Geothermal heat pumps can be used just about anywhere in the United States because all areas have nearly constant shallow ground temperatures—although systems in different locations will have varying degrees of efficiency and cost savings.
15 Fun Facts: Geothermal Energy
- The largest hot spring in the world is Frying Pan Lake in New Zealand.
- Today, geothermal energy is used in more than 24 countries around the world.
- Geothermal energy produces 0.03% of the emissions that coal produces and .
- Geothermal energy is more than 2,000 years old and is believed to be first used in China.
Technology can transfer heat energy from underground water to electricity, then it can also store the extra energy into underground water. Unlike other widely used energy storage such as battery, thermal energy storage, and solar storage, geothermal energy storage stores energy in subsurface groundwater.
The future of geothermal energyAmong the most recent systems for the exploitation of geothermal energy, the most promising are the third generation ones, also called EGS (Enhanced Geothermal Systems). Their technology allows to dramatically improve energetic efficiency of both geothermal wells and dry rocks.
