A new Floating Wind Energy Generator - May 4, 2023


Ali Mardani, Saeed Askary

The global energy resources is limited Also this limited energy resources causes greenhouse effect. Energy is vital need of civilization and without it all aspects of civilization endangered Also, the greenhouse effect of current energy resources have an adverse effect on environment. Ground mounted wind turbines that are installed on the ground has tower and wind turbine positioned on top of it turning but ground mounted wind turbines need large amount of structural materials. Floating inflatable wind turbines that filled with helium gas and tethered to the ground using a conductive tether The wind turbines turns and generates electricity transferred to the ground station via the tether but the floating wind turbine has a low mechanical efficiency because of the shape of the wind turbine. flying kites that are pulled by wind and it turns a ground mounted electrical generator generates electricity but flying kites are hard to control and needs a complicated stablizing mechnism and sometimes the kites get out of the control. In this paper, multi wind turbine wind energy generator This wind tubines consisted of a circular inflatable that is floating but turned by several cylindrical wind turbines turning the circular system. It has a higher mechanical efficiency. It is easier to control and stabilize.

KEYWORDS: Floating wind farm, wind turbine, wind power, electrical generator

The energy resources worldwide is ending and they releases green house gases causes the earth get warmer. It is estimated the fossil fuel energy last by future 50 years. Energy is the key need of human life now and any interuption in electricty can have adverse effect on several aspects of human life Also, current fossile fuel resources causes the earth temprature get higher and changes climate patterns into danrous climate pattern for nature and biological creature including human. The consumers in cities increase as the cities expanded and population increases The greenhouse effect of fossil fuel also makes the earth warmer. To solve this problem several solutions proposed so far. The wind turbines that installed on the ground and it has a tower with a windturbin on top of it connected to an electrical generator but the wind turbines that installed on the ground rquire large amount of structural materials for tower and foundation. Also, it needs a costing foundation and installation cost. Floating cylandrical wind turbines that are empty and filled with a ligher than air gas like helum gas and tetherd to the ground using a the tether and this tether also has a cable inside These floating wind turbine rotate around their axis and produce electricity This electricity is transferred to the ground via that cable inside the tether but the wind turbine which are cylandrical filled with ligher than air gas and are floating has a low mechanical efficiency due to this fact that they have a savonious style shape which has low efficiency. Futhermore, these wind turbines also can only operate at a low altitude as the tether length cannot increases due to its raising weight. the kites that are flying in the air and they pul a tether when wind blows and this tether becuse is turned around a drumi its turns the drum connected to an electrical generator on the ground generates electricity but flying kites energy generators need a complex control strategy and also not always this control strategy gurantees stability of it as the kiy flying in the air in higher wind speeds is unpredictable and very rotational. Moreover, the kite located at low altitude and it occupies a large territory. To solve these problems in past solutions, in this paper, a floating wind turbine with multiple floating wind turbines connected to it proposed. This wind turbine is has floating circular structure as the main body that seven other floating wind turbines are connected to it and rotate it.. this wind turbine can operate in high altitude where stronger wind blow. It has a significat mechanical efficiency because of its structure. The wind turbine uses cylindrical wind turbines filled with lighter than air gas that has a large energy production efficiency. This wind turbin is alway aloft and it will not reach the ground and the only problem remains is controling the pitch angles of the seven wind turbines in different wind speed. This wind turbine is more stable than flying kites.. The wind turbine uses cylindrical wind turbines filled with lighter than air gas that has a large energy production efficiency.

This new wind turbine is floating at high altitudes and consisted of several parts The first part is a cicular inflatable structure as seen in the image Fig1 This circular part that is filled with a lighter than air gas and is floating over the ground at a high altitude This structure has four aluminum rings These ring keeps the strengthen the the circular structures There are four aluminum bars also as diameter of the the circular structure The diamtere of structure is 10 meters The thinkess of the structure is 4 meters .
Fig. 1. The circular structure filled with helium gas lighter than air gas keeps is floating at a high altitude.
The second part is a metal bar connects the center of circular structure to ground based generator as seen in Fig2 This metal bar is made of compressed carbon It is light weight and strong It acts as the shaft of the circulart structure and when the circular structure turns the bar also turns.
Fig. 2. The shaft of the ciruclar structure which is a strong light weight bar.
The third part is a electrical generator positioned on the ground and it is turned by the metal bar as its prime mover as shown in Fig3 It is a permanent magnet electrical generator The generator is fixed on the ground The genertor shalf is connected via joint to the carbon-bar (shaft of the circular structure) This joint allows the bar to rotate the electrical generator shaft at different angles Because the shaft of the circular structure is not vertically connected to electrical generator shaft Depends on the wind speed the ciruclar structure causes the carbon-bar aligns at different angles compared to the ground.
Fig. 2. The ground-based electrical generator that is rotated by the shaft of the circular structure.
The third part is the Gas Filled Savonius Style (GFSS) wind turbine are connected to the circular structure and they turn it GFSS are cylandrical shap structure that is filled with ligher than air gas This type of wind turbines are savious shape wid turbine It turns around its horizontal axis GFSS has diamtere of 3 meters and length of 6 meters The GFSS wind turine not only pull the circular structure but also turns around itself because a small permanent magnet generator is connected to the shaft of this GFSS wind turbine One one of such GFSS wind turbine connected to the circular structure shown in Figure 4.
Fig. 3. Gas Filled Savonius Style (GFSS) wind turbin connected to the circular structure.
In fact totally 7 GFSS wind turbines are connected to the cicular structure Once the wind blows, these turbines not only rotate around and generates electricty but also they pull the circular struture and rotate it as well as shown in Fig5.
Fig. 4. Seven GFSS wind turbines connecred to the ciruclar structure.
As seen in Fig6, the GFSS wind turbines are floating at a higher altitude than the circular structure They are tetherd to the cicular structure Each GFSS wind turbine is connected to the cicular structure using two tethers as shown in Fig 6.
Fig. 5. The seven GFSS wind turbines rotate altogether the ciruclar structure causes rotation of the carbon-bar rotates the ground based generator.
The generated electricity by the generator of the GFSS wind turbin transferred to the circular structure via the tethers and then from there is tranfered to ther ground via that bar becase a cable also is inside of the bar At the ground station, two electrical brushes get the electrical energy from the bar In fact the long bar transfer both electrical and also machnical energy.
Fig. 6. The carbonbar transfers both electrical energy and mechanical energy from the floating circular structure to the ground.
Considering a 10 meter diameter circular structure and thinkess of 4 meters, with GFSS turbine with diamtere of 3 meteres and lenght of 6 meters, the generated electricty at wind speed of 30km/h will be 18KWh. At very high speed the deviation angle of whole floating wind turbin to the ground will be low but it still will be at a high altitude and generates electricty according to calculations. A floating wind farm using such new floating windturbin also designed and its output power stimated. A wind farm with area of 1km x 1km with 200 number of such wind turbine can generate 3600Kwh in wind speed of 30k/h.
The proposed wind turbine occupy lower area as it is floating at higher altitude and only the ground is on the ground occupy a small area Also this new wind turbin can be used to make floating wind farms that has minimum enviromental beauty effect Because this wind turbin floating at higher altiutude and not visible from the ground This new wind turbin also generate more energy as it benefits high altitude winds that has higher wind speed and more consistent wind speed.

Due to greenhouse problem of the fossile fules which are limitted as well, there is a active seeking for extraction of renewable energies because electrical energy consumption also increasing worldwide Renewable energy generation technologies including wind power, solar power, water power, biomass, and nuclear power has several problems of cost or low efficiency To alleviate these problems a new airborn floating wind turbine propsoed The wind turbin floats at high altitude and generates electrical energy The propsoed floating wind turbine system parts explained in detail and it output power estimated and also a floating wind farm using such floating wind turbine also considered and its output power estimated Finally advantage of this floating wind turbine are explained.

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