Some Basic Information about Tidal Energy
Have you ever thought of renewable energy sources? What are these? From where we can find these renewable energy sources, solar energy or wind energy? But have to hear anything about tidal energy. This is an oldest form of renewable energy but not very commonly thought of while considering renewable energy ways. Tides can be caused by moon and its gravitational forces. Ocean wave energy is kind of hydro power which basically requires rising and falling of sea levels. These rise and fall of sea level is then converted into electricity through tidal energy devices.
There are different ways in which you can capture tidal energy. You can lay surface devices on ocean surface which capture electricity from the wave’s movement. You can also place horizontal and vertical turbines underwater, which are just like wind turbines as these can create electricity as the tide passes from the turbine. Reservoirs can also create tidal power, as you can place turbines at the face of the reservoirs and when the water passes through the turbine it will create electricity. If the speed, mass and height of water are at the peak level it, they will efficiently create tidal energy.
How tidal energy works
Tidal power is a massive source of energy that is known to mankind for centuries but how to produce electricity from it is discovered in recent past. If we properly use the ocean wave energy, then we can easily produce around 450TWh per year. Other than this the potential of electricity making from the river flow is yet to be estimated.
As it is discussed above that it is relatively a new concept, so not many companies investing in tidal energy projects. Still there are many tidal energy plants which are working and few are in developing stage. Few of these active tidal energy plants are just used for experimental and research purposes but some are used for commercial purposes as well and the number is on continuous rise.
La Rance tidal power station was among the first ocean wave energy project that was started in 1966. It is constructed on the river Rance, located in North-western France. This project has 24 turbines with a total of 240 MW installed capacity. This project produces around 600 GWh per year. It means that if we take average per day production from this power plant it comes to 68 MW per day. La Rance is a kind of tidal barrage power plant.
Tidal Barrage Energy
Tidal barrage power plant has three key parts. First one is the barrage, which holds water back in case through high tide. Sluice gate is the second part, it will let water through. Third part is turbine and generator that generates electricity.
Mostly when there are high tides the sluices gates remain open, but were closed during low tides. This is done to create water level differential. This will resultantly create difference in electricity generation.
Tidal Stream Generator
This is same as wind turbines expect these are under water surface rather than being above or on land. These turbines and generators translate the water movement that comes from variation in tide into electricity. As water is 830 times denser as compare to air, so it is easy to generate electricity at less speed than wind turbines.
Dynamic Tidal Power
This concept is still in development stages. The basic theory behind this concept is that we can generate tidal power and then electricity through the interaction of tidal flows with kinetic and potential energy.
Advantages of tidal energy
Tidal energy sources come from the gravitational movements of sun and moon as these creates high and low tides. When you think of it, it means that the ocean wave energy sources are renewable as compare to fossil fuels and nuclear reserves, moon and sum gravitational fields is not though of to be ceased in near future.
Other than being a renewable energy source, it is also an environment friendly option. The good thing is that it do not emit greenhouse gases as well as don`t take a lot of space. Currently there are many studies going on about the advantages of tidal energy for environment.
Mostly sea currents are predictable, these develop with well-known cycles, and it will make it easy to construct ocean wave energy system with accurate dimensions.
Low speed effectiveness
As water is denser than air so it makes it easy to generate electricity even at low speed. As per the calculations, it is seen that the power can easily be generated at 1 minute per second.
If you become able construct a good tidal energy source, then your import of fuel will surely decrease and it will allow you to meet the growing need of electricity from within your own sources rather than depending on fuel import.
In case of bad weather conditions and storms these barrages and dams that are constructed for electricity generation can protect your coastal areas and ports from dangerous tides.
Disadvantages of tidal energy
Intermittent Energy Source
The biggest disadvantage associated with tidal energy is that it is intermittent source of power because it can only produce electricity when tide surges. On average it happens for about 10 hours a day. So if you are working with tidal energy then you should also ensure some proper storage solution to get the maximum benefit.
If you consider the monetary aspects of tidal energy, then you can find that because of the new technology, it is still an expensive choice. Experts says that this source of energy become profitable on large scale near 2020 with the invention of new technology. Another thing that increases cost of such project is the upfront investment in shape of construction of plant.
The time and money that you have spent or are intended to invest on tidal energy project is very high. Sometimes you may have started a project but cannot be able to complete it within its given time frame.