Tidal Energy Pros And Cons
Tidal energy also known as the power of the tides is a form of hydropower that turns the kinetic energy of the tides into mechanical energy, which is used to spin a turbine and generate clean electricity with the help of generators.
The tides on planet Earth are produced by the gravitational forces of the Moon, Sun and Earth combined that are applied to the water surface of the oceans.
The level of the tides have different values depending on the position of the Moon and the Sun towards the Earth.
When the gravitational forces of the Moon and the Earth are aligned, they become very strong and they produce the “high tide” which represents the movement of a very large volume of water in our oceans towards the shores.
When the gravitational forces of the Moon and the Earth are at an angle of 90 degrees to each other, the “low tide” will be created, which means that the large volume of water in our oceans will be moved back to its initial position (away from the shores).
A tidal cycle consists of a high tide that is followed by a low tide.
All coastal areas of the planet receive in a time period of 24 hours and 50 minutes two high tides and two low tides.
If the gravitational forces of the Moon are aligned perfectly with the gravitational forces of the Earth and the Sun, a very high tide will be produced, which will be followed by a very low tide in the same tidal cycle.
Pros Of Tidal Energy
Tidal energy like all the other forms of clean and renewable energy available on the planet have more pros than cons, which makes them to be the perfect energy sources for the clean future that will follow.
1. Is A Renewable Energy Source
The tides on planet Earth are generated by the gravitational forces of the Moon and the Sun, which means that tidal power is a renewable resource because the Moon and the Sun will be here to create tides in our oceans for another 4 to 5 billion years.
Being a renewable energy source, tidal energy is considered one of the clean and green energy sources of the future.
2. Is An Alternative Source Of Power
Being an energy source that is renewable (never ends) and also clean (does not pollute), tidal energy is also considered an alternative energy source because in the future, tidal power along with the other alternative energy sources available on the planet, will replace the dirty fossil fuels such as coal, oil and natural gas in terms of energy production for a future without pollution.
Tidal energy alone cannot replace the dirty fossil fuels as the main source of power on the planet, but along with the other alternative sources of clean power, such as: solar, wind, geothermal, biomass, nuclear fusion, etc. will be capable to replace all these polluting fuels that are used today on a mass scale.
3. Is A Predictable Source Of Energy
Despite the fact that the other renewable energy sources known today, such as solar and wind power (energy sources that are generated by the Sun), are intermittent sources of energy, tidal power is also produced by the gravitational forces of the Moon and Sun, but even so, tidal energy is a highly predictable power source.
Tidal cycles are predictable, and this way the power output of a future tidal power plant can be easily calculated before building the plant, and scientists will know this way if building a tidal power in a specific coastal area is sustainable (if the tides are high enough).
4. Tidal Power Plants Are Long-Term Projects
Because tidal cycles never go out (the gravitational forces of the Moon and Sun are always applied to the water in our oceans), building a tidal power plant is a project that will produce clean electricity for a very long period of time.
Having parts that can be replaced, a tidal power plant can work for decades if the sea currents and the height of the tides remain the same.
5. Tidal Energy Is Cost-Effective
A power plant that burns fossil fuels has a life span a few decades, while a tidal power plant can work much longer (at least one century).
Besides this, a tidal power plant can be effective even at low tide speeds, producing power that will bring down the overall costs.
6. Tidal Power Plants Are Storm Surge Barriers For Shores And Naval Ports
A tidal power plant is usually built in the area between the coastal area and the sea or ocean, which means that the facility will stay in front of a storm that tries to violently hit the shores.
These power plants can protect even naval ports that could be heavily affected by the presence of a violent storm in the area.
Cons Of Tidal Energy
Like almost all the other renewable energy sources available on the planet, tidal power has its own disadvantages mostly related to the upfront prices and the effects on the environment.
1. Being A New Technology, Tidal Energy Is Expensive
Being a new form of clean power, tidal energy is not cheap.
Building a Tidal power plant in the coastal area where the tides are high represents a pretty expensive investment because we are dealing with relatively new technology.
Even if today, tidal power is considered an expensive form of renewable energy, by the end of this decade (2020), tidal energy will become commercially effective by using improved technology and a larger number of power plants built all over the planet.
2. Tidal Power Plants Can Affect the Local Environment
Tidal power plants are usually built near the shore and they are using turbines similar to the ones used to produce wind energy.
The only difference between wind turbines and tidal turbines is represented by the fact that tidal turbines are using reversible electrical generators in order to produce energy both at the high and low tides.
The presence of the vertical turbines spinning underwater will always affect marine life that swims in the area close to the turbines and can also disrupt the tidal cycles.
3. Tidal Barrages Can Restrict Access To Open Water
Tidal barrages are usually built across bays and estuaries, and they look like dams that are using the tides to generate clean electricity.
Being built across bays and estuaries tidal barrages restrict the access to open water.
4. The Places Suited For Harnessing Tidal Power Are Limited
Tidal power plants require a certain level of the tides, which is not so easy to find on the planet.
However, scientists are working today to produce tidal turbines that can produce electricity even in very low tides and are also more friendlier with the marine life.
5. Tidal Power Plants Can Change The Tidal Level In The Surrounding Area
The presence of a tidal power plant, tidal barrage or tidal fence can reduce the tidal level in the surrounding area.
The underwater turbines will use the kinetic power of the tides to generate clean electricity, and the water that escapes the spinning turbines will loose almost all its kinetic power, which will reduce the level of the tides in the area.
Tidal power plants require a certain level of the tides, which is not so easy to find on the planet.
Conclusion
Scientists are working today to produce tidal turbines that can produce electricity even if the level of tides is very low, and are also more friendly with the marine life interacting with the turbines.