Ocean waves is one form of energy that can be exploited by knowing the wave height, wave length, and time periods.There are 3 ways to capture wave energy, namely:
1. Buoy: electricity is generated from the vertical and rotational movement pelambung.
2. Oscillating water column (Oscillating Water Column): electricity is generated from the rise and fall of water due to waves in a hollow cylindrical pipe. Rise and fall of the water column will result in exit and entry of air at the top of the pipe hole and turn the turbines.
3. Wave Surge. This equipment is also commonly referred to as tapered channel or canal taper or tapchan system, mounted on a channel structure that was built on the beach to concentrate the waves, took him into the pool of the elevated reservoir. The water that flows out of these ponds are used to generate electricity by using standard hydropower technologies.
This energy can be converted into electricity through two categories: off-shore (offshore) and on-shore (beach). Categories offshore (off-shore) is designed at a depth of about 40 meters by using mechanisms such as the Salter Duck coil created Stephen Salter (Scotish) which utilizes the movement of waves to pump energy. These systems utilize the relative movement between the part / outer (external hull) and the pendulum in it (an internal pendulum) to be converted into electricity. Equipment used to float the pipe fittings on the surface that follows the wave motion. Ups and downs of buoyancy effect on the subsequent drive the rotation of the pipe connecting the underwater turbines.
In the United States, there have been companies that develop a string of plastic buoys buoys that support this electricity producer. Each Buoy buoy can produce 20 kW of electricity and has now been developed to recharge (recharge) for the U.S. Navy submarine robot and used for small communities. Another way to capture wave energy offshore is to build a special place like Matsuda tube system, method is to utilize the incoming wave motion in the lower chamber in the float and causing the displacement movement of air into the top of the buoy. The movement of this air displacement turbine. Marine Technology Center of Japan has developed a prototype of this type is called 'Mighty Whale' of a wave catcher equipment is in place on the sea floor (anchored) and controlled from the shore to the electricity needs of small islands.
The system converts the on-shore coastal waves to produce electrical energy through 3 system: channel systems, float systems and oscillating water column systems. The principle of mechanical energy that is created from these systems directly activate the generator by transferring the wave in the fluid, water or air mover which then activate a turbine generator. In channel systems are transmitted through a channel waves into the trap of building such artificial pond (lagoon).
When the wave comes, gravity will force the water through turbines to generate electrical energy. On float systems that govern the form of a string of hydrolic pumps rafts associated with the hinges (Cockerell) moves up and down following the relatively moving gelombang.Gerakan hydraulic pump which is between two rafts. Kayser upright tube can also be used with a float that moves up and down in it because of water pressure. Movement between the buoy and the tube causing the hydraulic pressure which is converted into electrical energy. Oscillating water column systems use waves to push air between the containers. When the waves get into the water column resulting container column lifted and fell again so that there is a change in air pressure. Circulation is happening to enable the turbine as a result of pressure differences that exist. Some systems serves also as a wave breaker 'breakwater' like on the beach Limpit, Scotland with electrical energy generated by 500 kW. There are four wave energy technology that Cockerell raft system, upright tube Kayser, buoy Salter, and Masuda tube.
Cockerell raft system shaped string of rafts are interconnected by the hinges and the system moves up and down following the wave of the sea. Relative motion rafts moving hydraulic pump which is between two rafts. Kayser upright tube system uses a float that moves up and down the tube due to water pressure. Relative motion between the buoy and the tube causing the hydraulic pressure that can be converted into electrical energy. Salter buoy system utilizing the relative movement between the part / outer (external hull) and the pendulum in it (an internal pendulum) to be converted into electrical energy. In the tube system Masuda method is to utilize the ocean wave motion into the space under the float and cause the displacement movement of air in the room above the buoy. The movement of this air movement can move the turbine udara.Lokasi potential to build a wave energy system is on the high seas, latitudes and in coastal waters. Wave energy can be developed in Indonesia in the south seas island of Java and Sumatra.
The workings of this new power plant is very simple. A concrete tube mounted at a certain height on the beach and the tip placed below the sea surface. Each time there are waves coming to shore, the water in the concrete tube that will push the air contained in the tube which is located on land. When the waves receded, air movement that otherwise occur in the tube earlier. Air movement back and forth is utilized to rotate the turbine which is connected to a power plant. A special device mounted on the turbine, so that the turbine rotates in one direction only, although the direction of air flow in the concrete tube turns.
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Its original object ganSpoiler for description:
Water Column Moving to and fro (OWC): Water column moving to and fro and researched all of the tools developed from the coastline. Water column moves to and fro using a structure which is partially dive to take advantage of potential and kinetic energy includes an ocean wave. To build the necessary OWC is a major concern because the whole site should be "dry". A barrier wall is generally built on top / side of the ocean area of construction. Although this tool is much easier to access than the cost of building offshore generator of a barrier wall is important. The part of the structure is hollow with a port on the back of the turbine / generator good (Figure 1). Medan wall extends into the water and the need to fully dive continuously. In connection with this purpose that the tidal fluctuations should be relatively small compared to the size of the structure of [it].
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Assume that the red lines persuaded to continue to figure 1 is represented by the water surface. If this is the case, when the waves are coming / next channel into the structure, a portion of the airflow will come off the opposite direction because the wave will not exist "seal" the air force until the port on the back of the wall structure. Like that, the tidal fluctuations should not drop below the edge of the base field wall in order to maintain operational parameters. When the wave approached, it causes the air to force so that the space / area and out of the harbor, near the back wall. When the wave retreated opposite direction, the air drawn from the port on the back wall to the turbine and the outer wall near the entrance to the field. Turbine either by itself is a major breakthrough in the implementation of the OWC, the use of two-way rotation direction generators. While OWC has tremendous potential when applied to ocean energy has several drawbacks. Initial cost of the barrier wall and the attachment is very high because most of the placement is the entrance to the machine. In general, coastal places are hard to obtain, depending on zoning. Moreover, the location of these reefs are worth to placement of the various types of ocean life and sometimes that is protected under the law. As previously, the main problem with OWC taking advantage of bi-directional air flow is present. Use of a Mechanical Turbine combines with an induction generator is a typical manifestation of an OWC.
The advantage of this wave of energy utilization are:
1. This energy is free, no fuel, no waste / pollution
2. Renewable energy sources
3. Can generate a lot of energy
4. The cost is not expensive
While weaknesses are:
1. Depends on the characteristics of the wave, it can sometimes produce great energy, sometimes nothing.
2. Need an exact location where the waves consistently great.
3. Appliance should be sturdy so resistant to bad weather conditions
Turbine well:One of the biggest problems that include wave power generation is the simple fact that the sea state is an element that is very nature to destroy, especially when in relation with mechanical parts to determine the period. This has been solved in the design of OWC with the use of forced air instead of seawater to turn the generator. The next problem encountered is the attempt to use both air flow presented by the OWC. Both turbine has been designed by Alan Well in 1980. Pumpun primary is to develop a turbine that can receive a two way flow in the direction that only rotate in one direction, ignoring the direction of water or airflow. As shown in figure 2-b, blade design innovation turbines themselves are good.Blade is similar to an air kerjang otherwise they are symmetrical about a horizontal axis, which is typically air kerjang is oval shaped in a state and not symmetrical. An air kerjang only use and lifting strength present, while the turbine is best to use it to lift and drag Kakas to obtain a self-rectifing the direction of rotation of the generator. When the space moved to the positive or negative things which direction the blade rotates in the same direction (figure 2-a).
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TAPCHAN:TAPCHAN was an abbreviation for the tapered channel and has designed and implemented by the Norwegian researcher in 1985. The location overlooking the ocean and surrounded by high concrete walls is a form of half-ball on each side (figure 3). Water entered the structure is a value / class a little [as / when] is approached from the beach with a reservoir on the far side. The channels are very wide area nearest to the sea and sharpen to a smaller width when approaching the reservoir.
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When the reservoir fills an urgent water channel toward the reservoir, a turbine housing. Spinning turbine to produce electricity, which is very similar to a power station hydroelectric. This arrangement requires a perfect average vibrational energy in order to have enough power to push most of the water into the reservoir. Moreover, tidal changes can no longer 1m from high to low tide to ensure that the reservoir was full corset.
Potential ResourcesTo predict the power that can be raised on the beach performed by using wind data. The wind is blowing on the surface of the sea are the main factors causing sea waves. The wind that blows across the water will move its energy into the water. The longer and the stronger the wind blows, the bigger the waves are formed. According to the theory of Sverdrup, Munk and Bretchneider (SMB), the minimum wind speed to generate a wave is about 10 knots, equivalent to 5 m / sec. To convert height and wave period used for shallow water wave equation (CERC, 1984). The equation used is:
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Where:F = fetch lengthUA = wind stress factorG = acceleration of gravityWhile the power that can be generated from wave energy is calculated using the wave equation, namely:
P = 0:55 H2S Tz kW / m (3)
where P is the power (kW / m wavelength), H is wave height (m), S is the period (seconds), and Tz is the zero crossing period.
Conclusion:Within both tools we have to evaluate each on its own services and the placement of the desired implementation. Both these tools have a great potential, just because the lack of interest in renewable energy applications of new technologies has not occurred. With more research and funding both of these tools can have a much wider application area.source