Sea current generation – the main power of Vietnam in the future

Sea current generation – the main power of Vietnam in the future

So the warming up of the earth by the greenhouse effect from using of fuels such as oil and coal is a disaster that people face. The loss of lives when people face the storm is much less in the face of flash floods, floods of rain on arriving of storms. With the human life perspective above all, reservoirs should prioritize flood control rather than the task of generating electricity. Wind power and solar power are also expensive. What kind of electricity resouce do Vietnamese people need to develop their economy?
The author believes that it is the sea current generation in the Central and South of Vietnam.
Hydropower uses water energy when moving from high to low to generate electricity.
Hydroelectric power is described by the formula W = mgh

 

Figure 1A :  Natural water current have the depth and the breadth

Sea currents generation use natural flow to generate the electricity.This energy is described by the formula W = 0.5mvv.
First of all we need to know why the energy resource of sea currents on this earth are concentrated in Central and South Vietnam.
Bottom circulating flow is formed by the difference in temperature.
In the experiments, we discovered that due to the temperature differences between the equator and the Arctic, a bottom circulating current flows along the central coast in 365 days a year in the southward direction.

As the earth turns from west to east, the current flow has moved from the Arctic to the Equator and at the same time has moved from east to west and created the currents along the Vietnamese coast from the south of Hainan island to Ca Mau cape.
The velocity of the bottom flow is the maximum value with three components:
1 / The thermal difference between the south pole and the north pole of the water area is the largest.
2 / The place where the bottom flow is present in the North Pole with latitude => 90 degrees.
3 / The southernmost part of the water area where the generator is located is latitude => 00 degrees.
The central coast is the only location on this earth that meets all three above factors.Therefore the velocity of bottom circulation in Vietnam central coast is the highest in comparison with other circuits in the world.

When researching the passenger car accident named 48K-5868 was flooded into the Lam River on 18/10/2010 in Ha Tinh province, the bodies have been drifted out to sea and are moving to the south at an estimated speed 0.386 m / s.
The above velocity is the average velocity at the generator location. Further research, we can see that at the location of the generator, the average speed also varies with the longitude and depth of the water.

The surface sea current formed by the wind
Vietnam is located in the monsoon area, so the monsoon created the surface sea currents for nine months a year, with an average velocity of 0.757 m / s.
Surface sea current velocity data is commonly used for use by vessels when navigating.
The Truong Son mountain prevents the Southwest moonsoon.
Thanks to the Truong Son mountain, the Southwest winds have little influence on the Vietnam Central Coast. Thus, the sea current in the Vietnam central coast being bold one-way currents is very suitable for conversion into electricity.
The above natural resource have been discovered by Eng. Doan Manh Dung and the author have gotten the Copyright in Dec. 2014
Sea curent at Vietnam central coast have six advantages that are aimed at exploiting into commercial electricity :
1- Near shore.
2- Seabed is shallow,
3- High velocity.
4- Direction north – south line stability.
5- The width is very wide (24 km at the mouth of Gianh)
6- Length of sea currents is very long (1000 km from Hon La – Quang Binh to Ke Ga)
The four factors (1, 2,3, 4) by US and Taiwan experts commented and published 3/2015.
Eng. Doan Manh Dung confirmed two last characteristics (5 and 6).
With these above characteristics of sea current, we understand that the Vietnamese ancestors left the generation behind an clean, endless source of cosmic energy that would last forever in the same state of heat and rotation of the earth.
The question is what technology will Vietnam use to convert the above energy into electricity?
The world today uses the following types of blades to convert the kinetic energy of natural flow.

Figure 1: Types of blade in the world for coverting the kinetic energy of natural folow.

The above blades are placed in a horizontal, vertical or tilt configuration to obtain the kinetic energy of natural flow.
The above blades in the world has four limitations:
1- The blade only receives kinetic energy in the woking area.
2- The weight blades should lose a lot of energy during converting from kinetic energy to electricity.
3- Sea current or winds have spilled by 47.7% as they crossed the traditional propeller system.

Figure 2: Model using wind turbine or water turbine
( Source : Wind energy – NXB Giáo dục – 2009)
Energy spilled by 40.7% when passing through the blades.
4- The force is partially lost before turning the rotor.
Force to touch propeller, divided into two parts, a part pushs the propeller that is useless, other part create moment of force to turn the rotor.
New solution of Vietnamese people
The new solution of the Vietnamese is “Doan Blade” called “Doan blade” to gratitude Doan family.
The rotary drum is a humming -top in the water. It has a drum shape, orbiting its axis. With the above rotating, the drum can delete the turbulence that have been appeared when a solid moves in water. The drum cover is fitted with a suitable blade. The rotary drum is internally vacuumed, so the Archimedes force let the rotary drum float in the water, thus reducing the weight of the drum. So the rotary drum is the ideal humming -top to convert the kinetic energy into mechanical energy and then convert the later into electricity.
The first test machine completed May 2016
The theory of rotary drum was presented at the Ho Chi Minh City Union Association of Science and Technology on 22nd June 2016.

Figure 3A : The Experiment No1

 

Figure 3 B : Model of sea current generator with “Rotary Drum” – Experiment 2.

 

Figure 3C : The Experiment No2 – view from front

 

Figure 4 : The Experiment No2 – view from top

 

The results of the second test machine presented at the Ho Chi Minh City Union Association of Science and Technology on 13rd Oct. 2017

 

Figure 5 : one unit with 14 rotors

Figure 6: Multi-module connection model for power plants in Vietnam central coast .

With the rotary drum model, all the forces acting on the drum are integrated as positive moments. The author uses a 3 degree diagonal directional wall so that the ability to convert kinetic energy into mechanical energy reaches 99.6% .
With the flow being unchanged by direction, we receive 100% of the kinetic energy itself in positive momments.
Thus, the leakage energy of the sea current is very small when it acts on the rotating drum to form the positive momments. In other words, the energy loss of the sea currents during conversion into the rotating mechanical power of the drum is the power that rotates the drum. This energy depends on the material, the radius of drum and the depth of the rotating drum. The loss is about 5-10% of the ocean current. We choose only 10%.
In the world, wind generators converted from mechanical power to electricity, achieve 70% efficiency.
With the above logic, the generators by the “rotary drum” flow model are expected to reach the efficiency of 70% (100% -10%) = 63%.
With a rotary drum model, the machine has a vertical axis so each module can exploit the full depth of the flow. Rotor and stator are located in the air , so the generator does not need water tight and low cost.
In order to see the full potential of sea currents and the ” Rotary drum ” application, the author introduces the following simple problem so that knowledge can be universally accessible.
Scientists from USA and Taiwan report that the sea currents in Vietnam central coast have the highest velocity in the western Pacific: v = 1.05 m / s to 1.26 m / s. Here we choose the low data v = 1m / s.
One sea current, the width is B = 1 m, depth is H = 1 m, flow velocity is v = 1 m / s , the energy of the above is E :
E = 0.5 m v v
1 m3 of sea water is 1034 kg; 1 kg = 9.8 N.
Output capacity of the above sea current is N= 0.5 x 1034 x 9.8 x 1 x 1 = 5066.6 W

One worker has an average power of 100 W, so the above energy source is equivalent to 50 workers.
Calculating output capacity in hourly power:
N = 3600 x 5066.6 W = 18,239,760 W / h = 18,239KW / h = 18.239 MW / h
The sea current generator with efficiency of 63%, the width of sea current – B = 1 m, depth of sea current – H = 1 m, flow velocity – v = 1 m / s can supply :
E = 18.239 MW/h x 63% = 11.49 MW / h.
If the depth H= 15 m and an average speed of 1 m / s, the sea current generator can supply :
E = 15 x 11.49 MW / h = 172.35 MW / h
Hoa Binh Hydropower Plant has 8 units, 1 unit with a capacity of 240 MW. Total capacity is:
E = 240 MW x 8 = 1920 MW / h.
The width of a hydroelectric power plant equivalent to that of the Hoa Binh Hydropower Plant:
1920 / 172.35 = 11.14 m
To have a Sea Curent plant equivalent to the Hoa Binh Hydropower Plant, it is only necessary to use a water area with a sea current velocity v = 1m / s, depth H = 15m and width B = 11.14 m.
The sea current in Vietnam Central coast with a depth of 10 m to 35 m, the width of it up to 24 km, the length of the current about 1,000 km can be installed 330 Sea current Generators Plant, it is a new and abandon energy that can help us to change the face of Vietnam economy.
We have these above figures because the sea water density is 832 times higher than air. Therefore, the exploiting water curent even in the mall velocity, but still bring a great effect.
Some people worry that the currents are natural flow, can not compress, can not change the direction … the author consider your thinks is the right concern and the author is confident that has solved by experiment, physics and mathematical theory.
Vietnam has tide power but amplitude is only 5m in the east sea coast of North and the South. However, it is possible to exploit tidal power in the following model:

Figure 7: The model for tide curent generator plant
The next step is that the Vietnamese need to find an effective institution to implement the goals and solutions that the State of Vietnam has advocated: Rich people, strong country, democracy, justice and civilization.
The author expects that the solution for justice must begin with respect for the hard work of others.

 

Figure 8 : The experiment existing  bottom sea current

 

Figure 9 : Velocuty vector of sea current in the northern hemisphere

 

Area of coordinates where contains velocity vector used for generator.

Dynamic currents energy are common in many countries, such as the northern coast of the Florida peninsula. The author hopes to find partners  to perform  the above idea in Vietnam and other countries. Please contact us by email: dungdzoan@gmail.com


Eng. Doan Manh Dung