Humans are now scrambling for alternatives to the depleting stocks of fossil fuels. Over the years, man has found several inexhaustible forms of energy such as solar energy, nuclear, wind energy, geothermal energy etc. Using these energies to back up the growing need for fuel has been successful to some extent. Renewable forms of energy need advanced technologies for harvesting and implementation. However, innovation and proper research in this direction have borne results.
Studies have shown that geothermal energy has been used since the paleolithic age. However, the first actual power generation was done in 1904. Currently,the United States of America happens to be the largest producer of geothermal energy, housing the largest development plant. Iceland is a close second with a lot of scope for geothermal energy harvesting.
What is Geothermal Energy?
Thetrapped heatin the earth’s core is tremendous, reaching 40000 C.The heattravels through the mantle and reachesseveral miles below the earth’s surface. Making it available for humans to harvest and use this thermal energy generated. Since we use the heat energy from the earth, it is known as Geothermal energy.
Initially, geothermal energy was used for bathing and heating purposes, and the non-availability of technology did not allow for commercial purposes. Now harvesting geothermal energy to generate electricity is one of the major projects several companies have undertaken.
How Does it Work?
A common way of harvesting geothermal energy is to use a geothermal heat pumpinstalled underground upto a depth of 10 feet.To pipes are then filled with water or anti-freeze solution,and water is then pumped around the pipes wherein the loops have been sealed. We can use thisto cool or heat the building according to seasonal requirements.
Types of Geothermal Energy
One of the methods employed is to use steam directly from the ground fractures and drive the turbines is called the dry steam system. Here two separate wells are drilled. One is used in the production well, and the other is the injection well. The production is used to extract steam and direct it towards the turbine.
When cooler, low-pressure water is mixed with hot, high-pressure underground water, the steam generated will help drive the turbines. This method of harvesting geothermal energy is called flash plants.
When a secondary fluid witha lower boiling point is used, the hot water from underground will enable the secondary fluid to turn into vapor and drive the turbine. This harvesting method is called a binary plant. They have an efficiency of 10-13%. However, it is considered the future of harvesting geothermal energy for large-scale purposes.
Geothermal Energy Basics
The production of geothermal energy on a large scale is possible when there are huge underground reservoirs that run a mile deep to harvest geothermal energy through hydraulic stimulation. Advanced geothermal systems to access the naturally occurring heat can help drive the turbines linked to generators that produce electricity for consumption.
Tapping steam and hot water from underground and using it for a variety of applications can help nations save money spent on importing fuel.If the geothermal reservoir is managed efficiently, then there could be a balance in the rate of energy extracted to the natural recharge rate of the reservoir.
Since the compactness of geothermal plants has been the calling card, unlike other fuels, which use more land hence a smaller footprint. However, doubts raised on the water consumption used for harvesting and its consumption are relatively less compared to the lifetime of energy output derived from the reservoir.
Electricity generation using a geothermal plant will requirethe voltage to be amplified to reduce the loss when conveyed on the grid, requiring highly insulated piping.
Geothermal Energy Advantages
- One of the major advantages of using geothermal energy is that it does not emit greenhouse gases hence an environment-friendly option.
- Since it is a renewable energy source, there is no fear of exhausting it, unlike fossil fuels.
- You can utilize the power generated by geothermal energy irrespective of weather conditions every day throughout the year without major disruptions
- The plants in greenhouses are now using geothermal water
- The energy is utilized to bring heat and cool homes and commercial establishments
- When geothermal water is piped under roads, it helps to melt the snow
- It is low on costs
- Warm water, exhaust heat, and other products generated during geothermal harvesting could be used for various purposes.
Since geothermal energy is clean and green energy that we can procure from the earth, it will help deal with climate change better. As the burning of fossil fuels to meet energy needs gets minimized, the dependency on them will come down. Exploring ways to harness geothermal energy the world over will enable us to make the switch and bring in the much-needed change for saving the planet.