Can geothermal energy be used to fuel vehicles?
Yes, geothermal energy can be used to power vehicles, in a roundabout way. When talking about geothermal energy, it simply refers to the heat energy generated by the earth’s internal forces, which makes its way to the surfaces. This heat is often harnessed to generate electricity via geothermal power plants, which is then used to charge electric cars.
What are the five main sources of renewable energy can be used to fuel vehicles?
A renewable energy source is a source of energy that is sustainable. It simply means that a given energy source cannot run out, or is so abundant it is endless, like the sun. Renewable energy sources are also called alternative energy sources.
This is because they are an alternative to commonly used non-sustainable energy sources that harm the environment, such as coal power plants. The main sources of renewable energy that can be used to fuel vehicles are:
- Geothermal Energy
- Solar Energy
- Wind Energy
- Hydro Energy
- Biomass Energy
Video – Is geothermal energy the way of the future?
Where does geothermal energy come from?
Geothermal energy refers to heat that is generated from the Earth’s core. Most of the geothermal heat harnessed for energy generation comes from regions located on top of tectonic plate boundaries.
These are regions of active volcanic activity. Alternatively, wells can be sunk deep underground to harness geothermal energy.
Geothermal power can also be harnessed by drilling wells deep into the ground to pump hot water, or steam, which is used to power electricity generating plants. This electricity can then be used to power vehicles.
Is geothermal energy renewable?
Geothermal energy is considered a renewable energy source. The reason for this is that there is an unlimited amount of heat energy that is generated by the earth’s core.
This applies even in areas where geothermal energy generation is dependent on a hot water reservoir. If the reservoir ever runs out, more water can be pumped in, which makes it a sustainable source of power.
Scientists have found that at the inner core of the earth, the temperature is around 10,800 degrees Fahrenheit. This is as hot as the sun’s surface.
In the mantle, the temperature ranges from 392 degrees Fahrenheit at the upper boundary to around 7,230 degrees Fahrenheit in regions bordering the core.
Since it would take billions of years for the earth’s core to cool, geothermal is considered an inexhaustible source of energy.
Where can geothermal energy be found?
Volcanoes are very hot, but often not suitable for harvesting geothermal energy
Geothermal energy is found in geothermal reservoirs, which are naturally occurring areas of hydrothermal resources.
These reservoirs are located deep in the ground and are mainly undetected above ground. The main methods by which geothermal energy finds its way to the surface are:
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Volcanoes
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Fumaroles
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Hot Springs
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Geysers
Most of the geothermal resources are near the boundaries of tectonic plates. These are areas where most volcanoes are located.
One of the most active areas of volcanic activity is the Ring of Fire, which is a region bordering the Pacific Ocean. That means regions located on the US west coast are some of the most suitable for harnessing geothermal power.
When magma wells up to the earth’s crust, it heats groundwater found within porous rocks deep in the ground. A hydrothermal feature comprises water and heat. Geologists use various methods and instruments to find the best geothermal reservoirs.
They also drill test wells, which they use to test the temperature of these reservoirs to identify the most suitable locations for setting up geothermal power plants.
Currently, one of the leaders of geothermal power generation is Iceland, which is renowned for its numerous volcanoes.
The country harnesses geothermal heath to produce nearly a quarter of its electricity. It also uses geothermal energy to heat office buildings, pools, and homes. Other countries that harness a significant amount of geothermal energy are:
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United States – 3,714 MW
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Indonesia – 2,133 MW
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Philippines – 1,918 MW
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Turkey – 1,526 MW
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New Zealand – 1,005 MW
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Mexico – 962.7 MW
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Italy – 944 MW
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Kenya – 861 MW
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Japan – 603 MW
How is geothermal energy used?
A domestic heat pump geothermal heat exchange system for home use
There are three main ways to use geothermal energy:
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Direct Use and District Heating Systems
Direct use and district heating entail using hot water from hot springs or underground reservoirs. It is one of the oldest use cases for geothermal energy and was used by the Ancient Romans, Chinese, and Native Americans.
Today, it is used to directly heat buildings or to heat multiple buildings via district heating systems.
When it comes to industrial applications, geothermal energy can be used for food drying, gold mining, and milk pasteurization.
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Electricity Generation
Electricity generation using geothermal energy entails using hot water or steam at high temperatures of 300° – 700°F. These plants are built near areas of geothermal reservoirs, which are around one mile below the surface.
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Geothermal Heat Pumps
Geothermal heat pumps use the stable temperature near the earth’s surface to heat or cool a building. A geothermal heat pump will transfer heat from the ground into the building during winter, and do the reverse in summer.
How does geothermal energy work?
Geothermal energy entails extracting heat from the ground to produce energy. This heat energy is usually in the form of steam.
The steam comes from an underground reservoir that is located in the ground, a mile or two below the surface. There are three main types of geothermal power plants in existence today:
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Dry Steam
A dry steam plant draws steam from the ground, which is piped directly to the power plant. It is then used to turn a turbine to generate energy.
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Flash Steam
Flash steam plants are the most common type of geothermal power plant. They use geothermal water reservoirs at temperatures higher than 360°F.
This superheated water flows up via cracks in the ground under its own pressure. As it escapes to the surface, the pressure reduces, and some of the water turns into steam.
This steam is separated from the water and used to power an electric turbine. Any excess water and condensed steam are injected back into the ground, which makes the whole process sustainable.
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Binary Steam
A binary cycle plant operates using heated water at lower temperature ranges of about 225-360°F. The plant uses heat from the hot water to boil a working fluid with a low boiling point.
The fluid is vaporized in a heat exchange, and as it expands, it is used to power a turbine. The water is injected back into the ground, where it is reheated. During the entire process, water, and the fluid are kept separate.
How can a car use geothermal energy as fuel?
How can geothermal energy be used in transportation?
Discover your solar saving potential
Geothermal energy can be used to generate electricity, which can be used to power vehicles, and electric trains.
Additionally, geothermal can be used directly to heat roads and other public infrastructure to de-ice them. For instance, it can be used to de-ice airport runways, greatly improving safety.
Geothermal energy can be used as a source of electricity
There are three main types of geothermal power plants. They are:
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Direct Dry Steam
A steam plant uses steam to turn turbines, which drive a generator that produces power. A steam plant eliminates the need to burn fossil fuels that are used to heat water to generate steam. This type of plant also eliminates the need to transport, and store dangerous fossil fuels.
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Flash and Double Flash Cycle
This type of plant is used where there is a reservoir with a temperature above 360°F. A flash plant entails spraying fluid in a tank, which is at a much lower pressure than the fluid, causing some of it to vaporize, or flash.
The steam is used to drive a turbine, which is used to generate power. Any remaining liquid can be flashed in a second tank via a double flash for extra energy.
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Binary Cycle
Most geothermal resources in the world are at mid-range temperatures of below 400°F. These areas are ideal for a binary cycle plant. Hot geothermal fluid and a secondary fluid with a lower boiling point are passed through a heat exchanger.
The heat from the geothermal fluid heats the secondary fluid, causing it to flash. The vapor is then used to drive a steam turbine.
Is geothermal energy expensive to use?
Geothermal heat extraction isn’t cheap – capital costs are high
Tapping geothermal is not cheap. It typically costs $2-$7 million per megawatt of geothermal energy generated. However, while the upfront cost is high, the outlay is easy to recoup as part of a long-term investment.
Besides that, federal and state incentives for green energy plants mean that geothermal power is competitive with other energy sources. For instance, power from The Geysers geothermal field in California is sold at a rate of $0.03 to $0.035 per kWh.
That is quite affordable compared to the state’s average cost of power, which is $0.025 per kWh.
Does geothermal energy use fuel?
Operating a geothermal energy unit such as a heat pump does not utilize any additional fuel. For instance, when operating a ground-source heat pump, the earth, groundwater, or both, are used as a source of heat during winter.
During the summer, the ground is used as the reservoir that extracts heat from the home during summer.
While geothermal heat pumps are not as common as air-source heat pumps, they are gaining popularity around the world.
Their main advantage is that they are not subject to extreme temperature fluctuations since the ground is a constant-temperature reservoir. The result is that they are a more effective type of heat pump system.
What fuel does geothermal use?
Geothermal energy is a naturally occurring source of energy. That means there is no external fuel needed to extract this energy. For instance, when talking about a hydrothermal energy source, the water is heated naturally by the earth’s internal temperature.
Pipes are only placed over the reservoir and used to direct the hot geothermal fluids to a steam turbine. No additional fluid is needed to keep the plant running once it has been set up.
What can geothermal energy also be used for?
The use cases for geothermal energy include:
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Geothermal Electricity Generation
Steam from geothermal reservoirs is used to turn steam turbines to generate electricity.
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Direct Heating Systems
Geothermal energy can be harnessed via heat pumps to heat a single home. They can also be used to directly warn people via a geothermal pool house.
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District Heating
Geothermal energy can be harnessed to heat multiple buildings in a given location by directing steam via pipes to the heating systems of buildings.
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Use of geothermal in Farming
In cold regions of the world, heat from geothermal reservoirs can be used to heat greenhouses, creating suitable conditions for producing food all season.
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Use of geothermal heat to maintain Infrastructure
Energy from geothermal reservoirs can be used to de-ice roads and runways.
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Industrial Use of Geothermal Energy Systems
Heat and steam from geothermal processes can be used for industrial processes. For instance, it can be used to dry food, extract minerals, pasteurize milk, and mine gold.
