Tidal Energy Advantages And Disadvantages
Tidal energy is a form of alternative energy that is part of hydropower, and turns the kinetic energy of the tides into mechanical energy to rotate an underwater turbine that will generate clean electricity.
The tidal cycles in our oceans are produced by the gravitational forces of the Moon, the Sun and the Earth combined, and can be used as a renewable resource of clean energy that can reduce our dependence on fossil fuels.
The underwater turbines used to generate clean electricity can produce electricity both at the high tide and low tide because they are using reversible electrical generators.
These generators will produce electricity even if the turbine moves forwards or backwards, so clean power will be generated during the entire tidal cycle.
Tidal power can be harnessed in almost all coastal areas of the planet where the tides are high enough to qualify for clean electricity generation. Let’ see what are tidal energy advantages and disadvantages.
Advantages Of Tidal Energy
Being a free form of alternative energy, tidal power is considered beneficial for the local economy because it reduces the consumption of fossil fuels.
1. Is A Free Form Of Alternative Energy
Tidal energy is a natural source of clean power that is part of the alternative energy sources, which will replace the fossil fuels in the future.
To reduce the use of fossil fuels for electricity and heat generation, we need to develop all the known resources of alternative energy (solar, wind, hydro, tidal, geothermal, biomass, hydrogen, etc.) because mankind requires huge amounts of electricity to power all its activities here on the planet.
Tidal power is available in many coastal areas of the planet, and we need to build a global network of tidal power stations to harness this clean and free energy source.
2. Is Part Of The Renewable Energy Sources
Tidal power is an alternative energy source that will replace the fossil fuels in the future, but it is also a renewable energy source because tidal cycles are produced every day by the gravitational forces of the Moon, the Sun and the Earth combined.
Being a renewable energy source it means that tidal power will be available for producing clean electricity as long as we live here on the planet.
3. Is An Environmentally Friendly Energy Source
The tidal cycles have appeared along with the formation of the world’s oceans, and they represent the cyclic movement of the ocean water towards the shore or away from it.
Being a natural movement created by the gravitational forces of the Moon, the Sun and the Earth, the tides are not affecting the environment in any harmful way.
Actually, the presence of the tides in our oceans is keeping alive some species of marine life, which means that these animals could vanish if the tides would disappear.
This way, the tides become beneficial for the environment and in addition, they can provide us with clean electricity to reduce our dependence on fossil fuels.
4. Is An Unlimited Source Of Clean Energy
The technology used to harness the power of the tides is quite new on the market, but evolves pretty fast and will be capable of using not very tall tides (as it is required in the present) to generate clean electricity in almost all coastal areas of the planet.
Today, the capacity to produce tidal power is limited because tidal power stations require that the tides to be pretty high (low tide needs to be at least 5 meters tall).
However, the technology evolves pretty fast, and in a not so far future from now on, we will be capable of producing tidal energy in almost all coastal areas of the planet, even where the tides are not very high.
5. Has A Great Potential To Generate Clean Power
The world ocean covers about 71% of the planet’s surface, which means that tidal energy has a great potential to generate clean electricity.
It is estimated that tidal power can generate about 700 TWh a year, which means that tidal energy can replace a huge quantity of fossil fuels burned every year for heat and electricity production.
6. Is A Predictable Source Of Clean Power
Tidal cycles are predictable because they are produced by the gravitational forces of astronomical bodies such as the Moon, the Sun and our own planet.
Every high tide is followed by a low tide, and all coastal areas of the planet receive two high tides and two low tides in a lunar day (24 hours and 50 minutes).
Being a predictable renewable resource not an intermittent one such as solar and wind power, the amount of energy output produced a tidal power plant can be estimated before even building the station, simply by knowing how high are the tides in that area.
7. Tidal Power Has High Energy Density
Tidal energy has a higher energy density (around 80%) than fossil fuels such as coal, oil and natural gas and also higher than the energy density of other renewable energy sources such as solar energy, wind power and biomass.
The high energy density of tidal power is mostly generated by the density of the seawater (1027 kg/m3), which is way higher than the density of the air.
This way, a turbine used to produce tidal energy will be more robust than a wind turbine and will generate more energy at the same size (aperture) of the turbine.
8. Tidal Power Plants Have Relatively Low Maintenance Costs
The initial costs of building a tidal power station are usually pretty high, but when the station enters into operation mode, it will produce tidal energy very easily and will have relatively low maintenance costs.
The team that operates the station will only need to monitor the tidal energy production and from time to time will need to perform small maintenance operations to keep the power station in good shape for a continuous energy production.
9. A Tidal Power Station Provides Clean Electricity For A Very Long Period of Time
A tidal power station works using flowing seawater which has a much greater density (compared to the density of the air used by wind turbines).
Working in such hard conditions, the tidal turbine needs to be very robust, and at the same time needs to protect marine life (fishes and other marine creatures will use an escaping corridor located in the center of the turbine to get away from the rotating turbine.
Being built to work in such a harsh environment, the tidal turbines used by a tidal power station will work for a very long period of time (over 50 years long).
Disadvantages Of Tidal Energy
There are also a few disadvantages related to tidal energy mainly produced by the high upfront costs required when building a new tidal power station and the impact on marine life.
1. Can Disrupt Fish Migration
The tidal stream technology requires the build of a tidal fence, which will harness the movement of the tides to generate clean electricity.
A tidal barrage usually closes a basin or an estuary, but the tidal fence is better because it can be used in open tidal channels located between the mainland and a nearby island, or even between two islands.
The problem with the tidal fence is created by the fence-like structure, which can block shipping and local navigation, and can also affect fish migration in the area.
2. High Upfront Costs When Building a New Tidal Power Plant
The technology used to turn the power of the tides into clean electricity is pretty new and quite expensive for the moment, but is still under development because we need to be able to generate tidal power cheaper even in coastal areas with low tide level.
At the same time, we need to protect marine life from being caught by the rotating blades of the turbine and we also need to create space for the migrating fish, which are usually affected when a new tidal fence is built because the fence-like structure will limit their movement through the water.
3. Several Natural Events Could Limit the Amount of Energy Produced by a Tidal Power Plant
A tidal power station produces clean electricity both at the high and low tide, but when natural events occur, such as frozen seawater, very low or weak tides, straight shorelines, a quick rise and fall of the tides, the power station will not be able to generate electricity.
4. Is Not Yet Commercially Viable
Once installed, a tidal power station can generate clean electricity with ease, and will require only daily monitoring and occasional maintenance service, but the high price paid for the technology, and the price of the studies regarding the impact on the environment are delaying the projects and are making the costs so high, that the entire project may lose its commercial viability.
5. High Tides Are Usually Located In Remote Areas
Coastal areas with great tidal potential are usually located in remote areas of the planet, which are quite far away from the places where the energy will be consumed.
Building power lines to send electricity from remote areas where is produced in populated areas is always difficult and very expensive, which will increase the price of the tidal project even more.
Final Conclusion
Tidal energy is still considered today a new form of clean and renewable energy source on the market, which means that we need to work hard if we want to exploit this awesome resource of clean power and transform it into something useful for mankind.
