14 Main Advantages and Disadvantages of Tidal Energy

Tidal energy pertains to a form of power that particularly transforms the efficiency of the tides to beneficial forms of dynamism. Though it is not widely used, it serves as a significant investment when it comes to electricity generation.

Currently, tidal energy is still in the early development stages, not being able to compete with fossil fuels. However, the focus on renewable energy sources and the demand for clean energy are contributing to a rapid development of methodologies to harness this type of energy source. Tidal energy is already offering many advantages, but put in mind that it is also linked to some disadvantages. In order to completely understand its significance and effects, it would help to gain a clearer understanding of these opposing aspects.

List of Advantages of Tidal Energy

1. It is renewable.
Tidal energy’s source is a result of the effects of the sun and moon’s gravitational fields, combined with our planet’s rotation around its axis, which result in low and high tides. With this in mind, the power source of tidal energy is potentially renewable, whether we are talking about tidal barrages, stream generators or the more recent technology, dynamic tidal power (DTP). Compared to nuclear reserves and fossil fuels, the sun and moon’s gravitational fields, as well as the Earth’s rotation around its axis, will not cease to exist any time soon.

2. It is green.
Aside from being renewable, tidal energy is also an environmentally friendly energy source because it does not take up a lot of space and does not emit any greenhouse gases. However, there are already some examples of tidal power plants and their effects on the environment. Important studies and assessments are being conducted on these things.

3. It is predictable.
Sea currents are highly predictable, developing with well-known cycles, which makes it easier to construct tidal energy systems with the correct dimensions, since the kind of power the equipment will be exposed to is already known. This is why both the equipment’s installed capacity and physical size have entirely other limitations, though tidal turbines and stream generators that are being used are very similar to wind turbines.

4. It is effective at low speeds.
Water is a thousand more dense than air, which makes it possible to produce electricity at low speeds. Based on calculations, power can be generated even at 1 minute per second, which is equivalent to a little over 3 feet per second.

5. It has a long lifespan.
So far, there is no reason to believe that tidal energy plants are not long lived. This means an ultimate reduction of the money spent on selling the electricity, making this energy source a very cost-competitive one. As an example, the La Rance tidal barrage power plant was constructed in 1966 and is still generating large amounts of electricity up to this day.

6. It reduces foreign importation of fuel.
By harnessing tidal energy on a large scale, we can help reduce foreign fuels importation and enhance energy security, as people would no longer have to rely much on foreign fuel import to satisfy the growing energy demand.

7. It serves as coastal protection.
Small dams and barrages, which are used to harness tidal energy, could protect ship ports and coastal areas from the dangerous tides during storms and bad weather conditions.

List of Disadvantages of Tidal Energy

1. It still has some environmental effects.
As previously mentioned, tidal power plants are suspected to have some environmental effects, but are yet to be determined. As we know it, these facilities generate electricity with the use of tidal barrages that rely on ocean level manipulation, thus potentially having the same environmental effects as hydroelectric dams. Also, the turbine frames may potentially disrupt the natural movement of marine animals, and the construction of the whole plant may also disturb migration of fish. Nevertheless, technological solutions are now being developed to resolve these issues.

2. It is an intermittent energy source.
Tidal energy is considered as an intermittent source of energy, as it can only provide electricity when the tide surges, which happen about approximately 10 hours per day on average. This means that tidal energy can only be considered as reliable when accompanied with effective energy storage solutions.

3. It should be close to land.
Tidal energy facilities need to be constructed close to land, which is also the place where technological solutions that come with them are being worked on. It is hoped that in a few years we will be able to use weaker tidal currents at locations further out to sea. In addition to this disadvantage, the areas where this energy is produced are far away from the exact locations where it is consumed or needed.

4. It is expensive.
We should know that the method of generating tidal energy is relatively a new technology. It is projected that it will be commercially profitable by 2020 in larger scales with better technology. Also, the plants that harness this type of energy are linked to higher upfront costs that are required for construction. Thus, tidal energy displays a lack of cost-effectiveness and efficiency in the world’s energy market.

5. It is not cost-effective.
The tidal energy technology is not that cost-effective, as more technological advancements and innovations are still needed to make power commercially viable.

6. It is still considered a new technology.
Still a more theoretic source of power, tidal energy is limited in real life to just a few prototype projects because the technology has just begun to develop and needs plenty of research and huge funds before it reaches the commercial status.

7. It requires long gestation time.
The time and cost overruns can be huge for tidal power plants, which led to some of them being cancelled, such as UK’s Severn Barrage. In fact, some tidal power stations, like the one being planned in Russia, will never be realized because of very long gestation time.


By weighing down the advantages and disadvantages of tidal energy listed above, you can gain a clearer realization on its over-all impact. On your end, do you think that this type of power source is more helpful to society, or not?

Author Bio
Natalie Regoli is a child of God, devoted wife, and mother of two boys. She has a Master's Degree in Law from The University of Texas. Natalie has been published in several national journals and has been practicing law for 18 years.