1. What is tidal energy?
Tidal phenomenon is the regular movement of seawater caused by the gravitational pull of the moon on the earth, and tidal energy is the energy generated by the tidal movement of the ocean. Tidal energy is a relatively new type of energy, it is clean and sustainable, as long as the construction of tidal power stations can be converted into a large amount of tidal energy into electricity for people to use. The following are the advantages and disadvantages of tidal energy generation:
2. Advantages and Disadvantages of Tidal Energy Generation
2.1 Advantages of tidal energy generation
2.1.1 Renewable
Tidal phenomenon is a continuous and universal occurrence in nature, in other words, tidal energy will not continue to decrease because of your use of consumption, tidal energy will never be depleted, so tidal energy is renewable energy, and tidal phenomenon will continue to circulate in one place, you can continue to use the tidal energy to generate electricity, to provide energy for you for a long time.
2.1.2 No Pollution
Tidal energy does not produce greenhouse gases such as carbon dioxide in the process of generating electricity, not to mention that it does not release toxic gases such as nitrogen oxides, which belongs to the category of clean energy, so tidal energy is pollution-free.
2.1.3 High energy density
Tidal energy is actually the use of the potential energy and kinetic energy of water, compared with the wind turbines using wind energy, it is important to know that the density of water is about 1000kg/m³ (at about 4 ℃), while the density of air is about 1.23kg/m3 (at standard atmospheric pressure), through the data can be known that the density of water is probably about 813 times as high as the density of air.
Therefore, the tidal energy generated by even a slow-flowing water current can far exceed that of wind energy. The high energy density of tidal energy is especially evident in places with fast currents or large drop-offs.
As an example, for example, the tidal power station located at the entrance of the Bay of Fundy in Canada, according to the relevant data shows that the installed capacity of the Bay of Fundy tidal power station is about 20MW, assuming that the capacity factor of the Bay of Fundy is 30%, then the daily power generation = Installed capacity × Capacity Factor × Daily Running Hours, and substituting into the data to get the daily power generation of 1.44×105kWh, we should know that the Bay of Fundy tidal power station is only about 250 acres. 250 acres or so.
2.1.4 Long service life
Tidal power stations are constructed with highly corrosion-resistant and pressure-resistant materials, and key equipment involved in the generation of electricity, such as the turbine generators, are coated with special coatings to ensure that they can withstand the erosion of water currents. These measures also contribute to the long service life of tidal power plants.
According to data, tidal range power plants typically have a lifespan of around 50 years. Tidal current power stations typically have a service life of around 70 years.
2.1.5 Highly predictable
Tides are a cyclical phenomenon with a fixed period, making the prediction of tidal energy far more accurate than other forms of power generation.
Take the Bay of Fundy tidal power station, assuming that the cross-sectional area of the Bay of Fundy is 1010 square meters, and the local gravitational acceleration is 9.8 m/s, calculate the potential energy of each tide = 1/2 × the density of water × the cross-sectional area of the Bay of Fundy × the square of the tidal difference × the gravitational acceleration, and substituting the data yields 1.25 × 1014 J. There will be two tides in the Bay of Fundy every day, and the potential energy of the Bay of Fundy’s daily tides will be 2.5 × 1014J.
2.2 Disadvantages of using tidal energy to generate electricity
2.2.1 Huge upfront investment
Tidal power stations require huge upfront capital investment because of their complex design, extremely stringent requirements for materials and construction structures, the need for workers with proven skills to construct them, and a construction cycle that takes several years.
According to data provided by the International Renewable Energy Agency (IRENA), the construction cost of a tidal power plant is roughly US$1,500 per kWh, and the construction cost of a large-scale tidal power plant may reach hundreds of millions of dollars.
2.2.2 Geographical constraints
Tidal power stations are mainly constructed in places with high tidal range or fast flow velocity, or undersea terrain with suitable water depth, and there are not many places that meet these conditions. According to the relevant data, there are only about 100 tidal power stations in the world, and they are mainly located in Europe and the northern part of North America, which is enough to see the limitation of geographic environment on the construction of tidal power stations.
2.2.3 Influence environment
First of all. The construction of tidal power stations will change the structure of the seabed, affecting the movement of underwater sediments, which in turn will make the underwater topography change, causing aquatic organisms to lose their habitats.
Secondly, the tidal barrage will block the migration routes of fish or other aquatic organisms, and the turbine generator in the tidal power station will emit a loud noise when it is working, which will affect the judgment of aquatic organisms on the direction. These conditions can have a significant impact on aquatic life.
Although tidal energy itself is a clean source of energy, heavy metals and other toxic chemicals can enter the water during the construction of tidal power stations and pollute the water supply.
2.2.4 High maintenance costs
Tidal power generators are always immersed in water and are affected by water currents, and as tidal power stations are large in size, their maintenance costs are naturally high, but they vary from one tidal power station to another.
For example, tidal range power stations require regular inspection of the dam structure and maintenance of facilities such as sluices and turbines, which entails high costs. Tidal current power stations are relatively smaller in size and hence have lower maintenance costs.
3. Is there a better way to generate electricity than using tidal energy?
The answer is yes. Solar power may be a better way to generate electricity. You should know that solar energy and tidal energy are both renewable and clean energy sources, but solar energy is prevalent in nature, so the use of solar energy is not limited by geographic factors, which makes it possible to install solar power generation equipment in your own home to provide power for your equipment.
Secondly, solar power system has been developed over several years and is not only technologically mature, but also inexpensive. Take monocrystalline solar panels as an example, this solar panel conversion efficiency of up to 30%, and the market price of $ 0.1 per watt, you install a 10kW solar energy system cost is in the 4000-6000 U.S. dollars or so, and the solar power equipment later basically do not need specialized maintenance.
It is worth noting that solar power stations can be expanded at any time, you just need to widen your space, and then buy the right solar equipment and install it, but the tidal power station obviously can not do so, it can be seen that the expandability of solar power generation is much higher than the tidal energy generation.
Finally, the construction period of solar power station is much shorter, and the construction process is basically no accident, according to the relevant data, solar power station usually only need a few months after the construction can be put into use.
In summary, solar power is applicable to a wide range of applications, including home use, factory use and national use, and can have a good output power, to a certain extent, is superior to tidal power generation.
Summarize:
Tidal energy power generation is an important means of reducing carbon emissions and advancing the cause of human environmental protection, from this point of view, the construction of tidal power stations need to be vigorously promoted, but there are still some drawbacks, so we need the relevant technical personnel to continue to improve the technology.
