Application of Ocean Wave Generator Equipment
K’Adesh A.D. Hepburn
University of Arkansas
Department of Electrical Engineering, Energy Systems
Fayetteville, Arkansas 72701

Abstract- This paper purposes the techniques and optimization of Ocean Wave Generation equipment. This paper analysis the characteristics and operational reformation of Power generation through Ocean wave technology, with special background in Oceanology. “Ocean energy has the potential of providing a substantial amount of new renewable energy around the world.(Carbon Trust 2006)” [3]. Ocean Wave generator equipment should be primarily use for power generation. Ocean wave can be advantageous due to nonexistence fossil fuel coal emission and nuclear radiation. The most basic functionality requirement of a generator in a wave energy converter (WEC) is that of mechanical to electrical power conversion – in similar manner to the functionality of a generator in a fossil fuel power plant. [2]. Oppose to on water oil rigs, whose residue still resides in the gulf coast. Ocean Wave generator can be the future of renewable energy. The gist of Ocean Wave generation relies mostly on kinetic energy of the tidal wave develop by the wind. Power generation can be control with an Ocean Wave generator. Research is also being conduct on Ocean wave harvesting allowing us to harness this energy. However, there is the question about Marine life, if there are any harmful toxins that can jeopardize the marine life in a particular area. The amount of money invested into this program and research in to this study. Also, relying solely on the environment is unpredictable. Inclement Weather, Natural disasters can cripple an environmentally dependent electrical grid leaving the area vulnerable. Ultimately, Ocean Wave generation can be revolutionary, further research can be committed to providing a fail-safe for natural disasters.

I. INTRODUCTION

Waves are caused by the wind blowing over the surface of the ocean. In most areas around the world, wind blows at a consent rate and force, this energy produce by the waves is potential energy along with the kinetic force being applied. The Ocean wave generator has the notion to extract energy from the motion of the moving wave.
The overall application of ocean wave equipment can be manageable, just as all the renewable energy. Solar is easy but very high maintence and expensive but a small load capacity. “The amount of electricity a solar panel produces is not only proportional to the sun’s intensity, but also depends on three factors: solar cell efficiency, solar panel size and the amount of sunlight directly hitting the panel.”[11] Wind Power can generate a great amount of power than can supply over 1400 homes. That only requires 4-8 mph wind. However, wind turbines are large and require large land masses and at very high cost. Although looking at renewable energy is a very high cost business, it is beneficial in the long run.

Figure1. Normalized resource time series for (top) wind turbine [2]

[pic]
Figure2. Normalized resource time series for WEC over a 40 s time slot [2]

Wave energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power plants and water pumps. Energy output is determined by wave height, wave speed, wavelength, and water density. To date there are only a handful of experimental wave generator plants in operation around the world. This paper explores the world of wave energy and its possible applications. According the renewable analyst, ocean energy wave and tidal resource potential is typically given in terawatt-hours/year (TWh/yr). This is shown by the figure3 and table1 below.

Figure3. Wave external power along the coast [9]

TABLE 1. Ocean wave Power across Coastal Region [12]
|Coastal Region |EPRI 2004 Estimate |Present Estimate Outer Shelf|
|West Coast (WA, OR, CA)|440 TWh/yr |590 TWh/yr (34% greater) |
|East Coast (ME thru NC)|110 TWh/yr |200 TWh/yr (82% greater) |
|East Coast (SC thru FL)|Not estimated |40 TWh/yr |
|Gulf of Mexico |Not estimated |80 TWh/yr |
|Alaska (Pacific Ocean) |1250 TWh/yr |1360 TWh/yr (9% greater) |
|Alaska (Bering Sea) |Not estimated |210 TWh/yr |
|Hawaii |300 TWh/yr |130 TWh/yr (not |
| | |comparable**) |
|Puerto Rico |Not estimated |30 TWh/yr |
|Total |2,100 TWh/yr |2,640 TWh/yr (26% greater) |

II. CONTRIBUTING FACTORS
[pic]
Figure4. Full converter topology [8]

Ocean wave generation is a common notion that is looked at in all areas and probably the least looked into as a primary source for power. As stated earlier, Ocean wave can be the future of renewable energy. Most countries were fortunate in making a better economy by this device. “Plans are underway to install 875 submerged turbines inside the Niagara River” [10] it is economical about the opportunities this kind of power can bring, let own the equipment used to build it. This requires less resource but a high demand of labor. In the economic sense, that is the goal of every economy, reduce unemployment but save money on exports (resources). This eliminates the constructions of dams, conduits and impoundments. “Similarly, the US Department of Energy is charting out plans to harness the tremendous amount of energy trapped in ocean waves, tides and currents.”[10] With the implication of this technology, there is reduction of marine lost, civil disasters due to natural causes.
Only investment needed in ocean wave application is the equipment and location. As stated earlier, the ocean uses both aspect of renewable energy, heat (sun) and wind. Location serves as an important, although the earth is made up of 70% water so we would want to take up the concept of having the transmission to be as little as possible in generating this much power. A heavy machine on the coast shore would look unappealing for those countries that rely on overseas visitor. A concept to adapt is that of an oil rig on water. Oil rigs generate over 10 million. The same concept can be used for the ocean wave technology but substitute the long drill for a turbine, buoy or oscillating water column.

[pic]
Where H=height, T=period, p=density of water, A=amplitude of wave. With this formula above, for a given wave period and height, we can compute the power that can be extracted per meter of crest of that wave. One can then use this formula, along with measurements of the average wave length and height to determine the available worldwide (or local) resources in terms of wave power. Ocean wave uses the same principles of physics, in terms of heat energy and pressure. Wavelength, amplitude, crest and tough are all taken into consideration in designing this equipment. In design this, these factor are taken into consideration, in addition, wind speed, which is depict below. As you can see we will be focusing on various form of wave, on the shallow and deep parts.
The velocity of idealized traveling waves on the ocean is wavelength dependent and for shallow enough depths, it also depends upon the depth of the water. The wave speed relationship is;

[pic]
Where λ=wave length, d=depth, g=acceleration of gravity. It we can be presumed that ocean waves obey the basic wave relationship c=fλ, where c is traditionally used for the wave speed or "celerity". The term celerity means the speed of the progressing wave with respect to stationary water - so any current or other net water velocity would be added to it. Any such simplified treatment of ocean waves is going to be inadequate to describe the complexity of the subject. It is certainly a subject that has been studied thoroughly, but no single model is going to apply to all cases.
“Tidal currents provide a highly reliable source of renewable energies. If one con-siders average time intervals of some minutes the current velocity is highly predictable and is designated as mean velocity hereafter. The mean velocity shows roughly four peaks per day in almost all locations in the world. As the current velocity in the open sea is too low to allow for efficient energy con-version, only sites where the currents are accelerated by narrows or other geo-graphical conditions qualify for the installation of tidal energy converters. One can assume that this requires peak currents above 2 m/s, which occur in many parts of the world. Some places even exhibit peak currents more than 8 m/s” [2]
There are a few draw back that makes this very risky, the ability to control the amount of power being generated. Having a fixed speed solution (wave speed) can assist the situation but a lot of factors are being lost, low energy capture, Mechanical stress, Power quality and reactive energy compensation. Another adverse effect of ocean wave equipment would be the environmental impact to marine life. In addition, the power distribution to enclose land base states that would traditionally cost more to send power. The cost for a startup and produce material would be expensive. Being the case, this would be a better investment as oppose to wind power, as stated; the wind has restriction and limitations as well. Although ocean has restriction as well, it is not limited as wind power and it is more diverse than any form of renewable power. Certain application can be implemented in most to any water-based area, including rivers and streams. This is further discussed.

III. TYPES OF OCEANS EQUIPMENT APPLICATIONS

This application of ocean wave generator technology is doable by the liberty it provides. There are so many factors, as mention earlier that contributes to this. All of these ways have been accounted for and provide a sense of raw creativity and principle to allow this project to be successful. Some actual concepts that were use are known as terminators, attenuators, point absorber, and overtopping devices.
Terminator devices are extended perpendicular to the direction of the wave. The captures the on shore wave, which acts as a piston in an engine, which pushes the air into the chamber, which connects to the turbine to generate power. This typical device generate from 500kW to 2MW. The power is also dependent on the size of the devices, and waves climate. Attenuators follow the basic principle like a ship, when waves hit them; they are extracting energy using fetters around the whole device. The force of waves along the length of the device, hitting it, causes contracting to the connect segments. The segments are connected to a hydraulic pump or a converter that generate power as the waves move across. There is a transformer in the bow of the device to steps up the voltage for transmission being led to shore. Power is then sent to an umbilical cable to a junction box in the seabed, connecting it and other machines via a common subsea cable to shore. “It was tested and operated in 2008. 3 miles offshore, using the Pelamus Wave Energy Conversion Device.”[9] A point absorber acts as a buoys; it’s a floating structure with components that move to wave action. Point absorbers often look like floating oceanographic buoys. The rise and fall motion of the wave height at a single point moves it’s up and down which is used for energy conversion. This can be closely related to the up and down bobbling motion caused by passing waves is used to drive electromechanical or hydraulic energy converters to generate power. Overtopping devices basically is a reservoirs filled by incoming waves, that buildup with water pressure like a dam. The water is then released, and gravity causes it to flow back into the ocean. The energy of the falling water is used to turn hydro turbines to generate power. There are specially built floating platforms that create electricity by channeling waves through internal turbines and then pumps it back to the sea.

CONCLUSION Ocean wave equipment is a very good investment, taking into consideration the pros and cons. Ocean wave technology provides economical sustainability as well as low cost, long term efficiency. The start-up will be expensive but the can be supply by distribution cost across the power supply footprint. Ocean wave equipment can eliminate the fossil fuel and tip over the renewable bridge towards the future. It’s reliable, reusable and affordable. “Ocean energy has the potential of providing a substantial amount of new renewable energy around the world.(Carbon Trust 2006)” [3]. Adopting this technique will beneficial as it upholds the level of excellence given by IEEE board and members. Ocean wave equipment helps maintain and improve our technical knowledge, as well as broaden our scope through the field of Electrical and electronics engineering. This is useful by skill individual who studied diligent into this field of power generation. It utilizes the concepts learnt throughout everyday life and build it to make a very good future., in addition, the safe implemented throughout this project would provide safe renewable energy for the world and help generate a bright future, and pave the way for a new wave of engineering, that can be develop an extend arm of electrical engineering.

REFERENCES

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