Often termed as the powerhouse of modernity, dams account for 16 % of world’s electricity. However, with countries quickly shifting towards greener forms of energy, they are constantly coming under public’s scrutiny. People have no second thoughts about the harm by other energy sources like coal and gas. However, opinion about hydroelectricity is still divided. So, now, let us look and the pros and cons of hydroelectricity and see whether it is really viable or not.
Today power generation capacity is spinning at a fast pace as the demand for power and electricity across globe is increasing year on year over crossing the supply. To meet with these uncontrollable demands, conventional methods of power generation is carried out through burning fossils, capturing wind and solar energy along with the classic source of energy from the available abundance of hydro space around the earth.
Hoover dam near Niagara Falls, Grand Coulee, and Boulder Dam are among the popular sites for hydro power plants across world. China’s dam in the upper Yangtze River with 18,200 MW of power makes it the most powerful in this globe. In US, the Grand Coulee Dam is the largest with 6,840 MW. The tallest hydropower dam in the world is the Rogun Dam situated in Russia with 335 meters height. Idukki dam in India gets the credit of Asia’s first and largest dam.
Whether it is the moving water or strongly falling waterfalls, the hydropower needs an abundance of this supply. Very similar to a wind power methodology, the hydropower generation requires a hydraulic turbine to convert the flowing water energy into a mechanical energy. This energy is in turn converted to electricity via hydroelectric generator attached. Hence the power of water flowing is a base for generating electricity and hence these plants are installed in a massive form to capture the water current to produce electricity for the world at large.
Though hydro power is considered a clean and safe source of electric power, the debate is still on to undermine its various ill factors affecting the eco system and habitat around. Let us understand the field reality by judging the good, the bad, and the ugly about this hydroelectricity.
Hydroelectric power is stored with many advantages.
1. Most Abundant:
World is surrounded by almost 72 percent of water bodies including oceans, rivers, lakes and streams. Availability of this resource is abundant and regular hence relying on the movement of these water bodies makes hydroelectric power an easy option for a long lasting power generation scope.
2. Power for years:
Once installed, it can yield productive result for generations to come. With its simple methodology and natural availability of water resources, it is a cost effective and reliable source of energy for decades. For instance, the Hoover Dam, which was constructed in 1922, is still an active source of electricity for three of the most highly demanding states in US – the California, Nevada, and Arizona.
3. Clean power:
The hydroelectric power does not burn fossils, do not depend on foreign fuel, and is not heavy for one’s household pocket. It just gives a clean form of electricity for homes and industrial houses. It is certainly a clean power source with its dams not emitting any nuclear waste or anything hazardous to the environment.
4. Low maintenance cost:
Apart from the initial cost of installation of these plants, the cost to maintain these plants is very cheap and cost effective. Take for instance the Hoover Dam, which did not need any renovation for almost 90 years since its inception. Only one large renovation was undertaken to refresh its state, else it is still going strong to capture the hydropower.
5. Renewable source of energy:
Hydroelectricity is one of the cleanest and renewable sources of energy, as it neither pollutes water nor reduces its quantity on earth. Hydro power plants make use of flowing and falling water and further recycle water by pumping it over and over again to generate energy. In addition, the natural hydrological cycle powered by the sun provides constant supply of water to hydro power plants.
6. No harmful bi-products:
Another advantage of hydroelectricity or hydro power plant is that it does not leave any air or water pollutants during power generation. Unlike nuclear power plants that generate electricity from a radioactive substance causing air and water pollution through radioactive rays and nuclear wastes, hydroelectricity does not produce poisonous bi-products and thus, keeps the air or water fresh and clean.
7. Helps preserve natural resources:
Hydro power plants unlike thermal power plants do not require any fuel to generate electricity and thus, help preserve natural resources, such as coal and fossil fuel, which are non-renewable and facing the threat of depletion. Hydroelectricity is a clean and renewable source of energy that does not interfere with the ecosystem.
8. Constant power generation:
While fossil fuel and thermal power plants rely on the available natural sources, which are fast depleting, hydroelectric plants with constant supply of renewable resource (water) and average life of around 100 years are a long-term investment that keep providing electricity for generations to come. In addition, we can control the power generation through the flow of water according to our needs and requirements.
Can this be better?
Though there is number of plus factors for this traditional hydro electric power, its visibility is not as significant as any other eco friendly power source like solar or wind. If more hydroelectric power stations and their networks are established across globe, it can pave way to reduce its hurdles existing as on date.
Hydropower in spite its effort to sustain energy efficiency, fails to attract the global market due to its existing limitations. As against the popular assumption that the hydropower is an environment-friendly source, in actual it affects the eco system to a large extent.
1. Hydroelectric power can seriously damage the climate:
Experts have confirmed that the hydropower plant dams can pollute the nature by emitting carbon dioxide and methane. The trees and plants around these dams, which get the direct heat of artificial flooding and decomposing underneath the dam’s bed, are considered the main cause for releasing these harmful greenhouse gases.
2. Global warming:
Methane is considered 21 times much stronger than carbon dioxide to effect the global warming. As the dams turbines indirectly let out the methane from the decomposed plants and trees underneath, they directly participate in global warming issue.
Can this be avoided ?
We need to clean these power plants at a regular interval of time. This can help in reducing the advent of buried flora under water. Though this procedure sounds expensive, it is just another option to avoid unwanted gases releasing into the environment. Also, use of alternate source of energy such as wind and solar can replace the existing system. It would help in avoiding any kind of pollution on earth.
The hydropower has a heavy price to its label. The cost of investment and its adverse effects on the habitat around is what makes it in the list of ugly. Expensive installing of the dams and turbines cost the sky. Only massive projects and industries can think of such investments.
Though once installed it does not call for any expenses of its own, it does make other habitats around to cry for help. This includes not just the trees and plants around but also the villages surrounding these dams.
To create electricity, the movement of water is well captured by these intelligent dams but equally result in artificial flooding. This flooding in turn drowns the existing green valley around and deprives local people out of their homes and livelihood of agriculture. Hence, to revive the nature back and provide a new shelter for people around does require a huge budget.
By adding significant portion of green house gas methane and carbon dioxide into global warming, it gets the not so environment friendly badge to it. The construction of Hoover dam is believed to trigger many earthquakes and altered the earth’s surface in that location.
In addition, these dams result in decreasing the dissolved oxygen level. This makes it extremely difficult for the fish and other marine species. Because of this, they suffer and diminish.
Five technologies that might make hydroelectricity greener
In view of the many dangers that large water reservoirs meant for hydropower can pose, there is a growing urgency to derive the same energy result without building dams. Fortunately, this urgency has spawned attractive concepts that could very well see us doing away with dams in the future.
1. Hydropower Kinetic Technology
Hydro Green Energy has developed turbine arrays that work on the principle of hydrokinetics. These modular turbines can be lowered and raised with the help of an on-board gantry, making it easier to conduct maintenance operations and doing away with the need to dive below the surface of the water to conduct checks. A floating raft acts as a platform for whatever operation needs to be undertaken. The rated capacity of the turbine arrays is 250kW per unit.
What difference will it make
This method of hydropower ensures that marine life is not disturbed and balance is maintained in the ecosystem. Unlike conventional hydropower, no dams are needed and the only requirement is flowing water.
2. FlipWing turbine
Seattle’s Hydrovolts Inc. launched the FlipWing turbine in 2010, with a view to generating hydropower without the use of dams. What is great about the technology is that the turbine can be used to generate power in shallow waters, serving as a solution to those areas where water bodies aren’t deep. The turbine is completely submerged and the blades are pushed against the center shaft by the current to drive the rotation. Incidentally, the technology is believed to be able to generate about 4kW of power. The company is currently working on building turbines of different sizes.
What difference will it make
The FlipWing turbine can be used in aqueducts and irrigation canals, offering areas with shallow water sources a chance to generate their own hydropower.
3. Free flow underwater turbines
Ontario’s Verdant Power has built free flow turbines as part of the Cornwall Ontario River Energy Project. The turbines work much like a wind turbine does, except that they’re powered by water. The blades are slow-moving to allow marine life safe passage through the waters.
What difference will it make
Verdant’s free flow water turbines can also be applied to harness tidal currents to generate more energy. And while the impact of this technology cannot be said to be nil, it is still a far safer option than conventional hydropower techniques.
4. CARE Electric
Johann Hoffmann is a name that is synonymous with eco-based inventions. Continuing his legacy of patenting innovative concepts, Hoffmann had CARE Electric Energia develop a turbine that generates electricity while protecting marine life and ensuring passage for small boats. The system is suspended in the midst of flowing water bodies while attached turbine blades rotate due to water flow and pressure that builds up from behind the installation. CARE Electric says that their system generates up to 90 percent of the total capacity of the generator which is substantially higher than conventional systems.
What difference will it make
The system, unlike conventional ones, can operate all year round to generate smooth supply of electricity. What is more impressive, however, is that CARE Electric’s system offers fish and small boats easy passage, maintaining the ecological balance and giving way for transportation and commerce.
5. Hydrokinetic river turbine
A hydrokinetic river turbine developed and installed by New Energy Corp and Alaska Power & Telephone respectively, is currently being used by the small town of Eagle, Alaska, to generate hydropower in a safe manner. The system has been attached to a barge and rotates at speeds slow enough so as not to disturb aquatic life. According to the makers, their system is capable of generating 25kW of renewable power.
What difference will it make
The system is beneficial where aquatic life is seen in plenty and offers towns the option of generating their own clean power.
Why are we so critical?
The hydroelectric power is there for decades. It is a classic source of providing electricity to the world at large. However more than its pros, its many cons. Moreover, all these that are getting into the eyes of scientists and activists. They are making this source of energy a real issue to debate.
In a recent study, it has been proved that the hydroelectric power dams facilitate emitting the carbon monoxide. This leads to global warming. They not just affect the eco system but also the marine life. It destroys fish and changes the flow of rivers and streams. Artificial flooding and huge investment towards it are also considered the main critical points against this system. For instance, during the construction of Three Gorges Dam in China, millions of people had to leave their habitat. The artificial flooding and unnatural flow of water has buried many important archaeological sites and monuments.
The Bottom line
Hydropower has been a great and economical source of generating electricity. However, with the advent of modern technologies and findings, this traditional system is under microscopic scrutiny. There are many research published against the use of hydropower. It is estimated that by 2020, the percentage of power from hydropower dams will come down to just 4 percent. This is also because there are no new plants or dams build on hydropower. Wind and solar energy are taking the center stage as a cheap and best alternate source of energy. Hence, it will not be a surprise to see the disappearing interest in hydropower electricity. However, this system will always remain as a simple yet effective source of energy in the books of records.