As the population is constantly rising, the need for more energy is always increasing. With most of our energy coming from fossil fuels and other non-renewable resources, it is important to find new ways to go about solving the energy crisis. Geothermal energy is a resource that has been in use for over 100 years; beginning with the use of hot springs for baths, engineers have since learned to harness its energy to transform it into electricity and use it for heating and cooling. It is a technique that can be used on small and large scales making it very accessible to everyone. On top of that, the fact that this energy is always constant makes it an ideal system for producing the energy we need.
The concept of nature producing energy for us is remarkable and the possibilities could be endless. As an enthusiast of the outdoors, I value the environment and think that preserving its health and beauty are very important. For this reason, I have always had a personal interest in alternative energy. There are always new frontiers to explore in the field of alternative energy where current technology can be integrated with nature. Solar, wind, and hydro are all innovative ways of harnessing our Earth’s energy, but geothermal is an area that is neglected fairly often. I believe that this alternative energy has considerable potential to make a positive impact on the Earth’s environment.
FROM HEAT TO POWER
Unlike other renewable energy sources such as wind and solar power, geothermal is always available and not dependent on outside forces such as weather. The core of the Earth is surrounded by molten rock called magma which heats the rock above it. This rock is what’s known as the mantle and right above that is the Earth’s crust. The magma beneath the Earth continually heats the mantle, which is why when the depth increases, more heat is accessible. For this reason, many hotspots for geothermal power plants are along tectonic plates’ edges or close to volcanic activity. Geothermal simply uses this heat via a series of pipes that contain liquids. They capture the heat and bring it to the surface, where it can produce energy using its heat to create steam.
In a geothermal power plant, energy is made in one of three different processes: flash, steam or binary. In a flash power plant, the water and steam that come out of the ground are separated. This steam is then used to power turbines and generate power while the water is injected back into the ground. The second type, a steam power plant, doesn’t need to separate the steam and water because it uses wells. Only steam is produced, which is used for the same purpose. The last type of power plant is the binary. In the same way steam turns a turbine, another liquid with a lower boiling point creates steam by a transfer of heat from the water to do the same job. This type is becoming more popular due to its ability to work with lower temperatures.
However, this is for large scale geothermal power plants. Only a short distance under the ground though, the Earth’s temperature remains relatively constant. For systems that typical homes would use, this area of constant temperature can be used to regulate the temperature within the house by circulating fluids through a series of pipes. Occasionally, pipes are also sent through ponds because of their relatively cool temperatures. These pipes can run through the walls and floors to keep a constant temperature within the house even better than many air-conditioning and heating systems.
WHY IT’S THE BEST SOURCE
Aside from being a reliable source at all times, geothermal provides a practical approach to cutting costs. In the year 2010, the world consumed approximately 18,466.458 billion kilowatt-hours (kWh) of electricity . To put this number into perspective, the average American home that year used about 11,280 kWh . The California Energy Commission on home installed geothermal systems has stated, “They can produce markedly lower energy bills - 30 percent to 40 percent lower, according to estimates from the U.S. Environmental Protection Agency…” . Less energy being used in homes can directly translate to lower energy bills which in turn can cause a butterfly effect if this technology is used by the majority. The United States took advantage of geothermal to produce less than 1% of its total energy consumed in 2011, while fossil fuels provided 68% of all the energy used in the U.S. that year . If all homes were to switch to geothermal heating and cooling systems, the relief to the power grid would be significant.
A factor that makes geothermal even more appealing is that it can be used for singular homes out of sight. By staying out of sight it will make homes more aesthetically pleasing as opposed to a typical heating or cooling unit outside the home. This system is also protected because it is totally contained beneath the ground. After Hurricane Sandy, plenty of homes had their furnaces and air conditioning units destroyed, but geothermal systems stayed intact because they were not out in the open . The other upside to these systems is that they use the constant temperature inside the Earth to not just heat the home but to cool it. After only a few years, these systems will even pay themselves off by cutting electricity costs since the heat and cold are just transferred instead of being produced.
In certain places, geothermal is in such abundance, it’s hard to even take full advantage of all of its power. Iceland, a country with lots of volcanic activity is capable of producing a good portion of their power with geothermal. So much so that they have enough to export to countries close by. However, currently they have no way of transferring the energy to these neighbors. While we continue to burn fossil fuels, this excess energy is just waiting to be tapped into. Similarly, China is a leader of alternative energies, but they have lost immense interest in this technology even though they have a country filled with hot springs and some volcanic activity. China has stayed ignorant like many others to the fact that geothermal has improved and come a long way since the 1980’s when their last benefactor to the science stopped funding it. The energy that could be produced with this resource is vast, and is more reliable than the other alternative energies that they use.
SKEPTICISM OVER GEOTHERMAL
Debate has come up over this method for collecting energy. In France, some initiative has been taken to use geothermal energy on a larger scale, but has been compared to fracking. According to French Environment Minister Delphine Batho, “Some will permeate rock using a process called “stimulation” that blasts acid and
water into fissures to release volcanic heat” . By this description, it appears very close to the process of fracking. It has also been said by P. Bayer through the German Federal Environmental Foundation that “An almost complete recovery is reached after a period similar to the lifetime of the project” . Fossil fuels comparatively take thousands of years to make a full recovery. Others claim that chemicals are released through the process of capturing the geothermal energy, but in fact, in some areas such as The Geysers in Lake County California, the geothermal plants act as filters because they trap most of the chemicals that are otherwise naturally emitted into the air .
THE NEXT GENERATION OF ENERGY
A resource that is this abundant and that is also renewable shouldn’t be looked over because faster way have been found to produce energy. I believe that even though it is proven that there are some drawbacks to geothermal energy, it’s an area that engineers should continue to research and work in. There is widespread agreement on the benefits of this alternative energy too; “A report published in 2007 by the Massachusetts Institute of Technology3 concluded that geothermal energy is the most promising low-carbon source capable of replacing fossil fuels for electric power generation” . Geothermal is a source of energy that we can afford to use and can in turn even help reduce our carbon footprint on the Earth.
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