Offshore wind power generation can generate electricity on the whole earth, but it also has a negative impact on the Earth's climate

ByVattenfall

Constructing several wind turbines on the sea away from the land and generating power by receiving a strong windOffshore wind power generationResearch has revealed that there is a possibility that all electricity used around the world can be created. On the other hand, however, it is also revealed that changing the wind energy on the ocean to electric power will cause the earth 's climate mechanism to collapse and have an unfavorable effect.

Geophysical potential for wind energy over the open oceans
http://www.pnas.org/content/early/2017/10/03/1705710114

There's enough wind energy over the oceans to power human civilization, scientists say - The Washington Post
https://www.washingtonpost.com/news/energy-environment/wp/2017/10/09/theres-enough-wind-energy-over-the-oceans-to-power-human-civilization-scientists-say/

This research was conducted by research teams such as Ken Caldeira and Anna Possner of the Carnegie Institute,Bulletin of the National Academy of Sciences(PNAS) has been announced. According to the contents, the wind blowing on the ocean is much stronger than the ones on the ground, and it has the energy that can generate enough electric power to support the earth's civilization.

On the ocean unaffected by the topography, more than 70% of wind is blowing than the land, and the idea of ​​offshore wind power generation is to convert this power to electric energy. In areas where research and development are being promoted mainly in Europe, researches are progressing to construct a huge offshore wind power plant off Chiba Prefecture and Akita Prefecture even in Japan.

In addition to the merit that the wind itself is strong at the offshore power, there is a characteristic that the efficiency is raised owing to the difference in the mechanism by which the wind is supplied. In order to understand this, firstly it is necessary to understand the phenomenon that when the wind rotates the windmill and generates electricity, the force of that wind weakens. When arranging several windmills in a straight line and hitting the wind from the front, it is the wind turbine that receives the wind the first time it is able to produce electric power most efficiently. However, in the second and later wind turbines, the efficiency of power generation is greatly reduced.

ByCGP Gray

When the wind hits the first windmill and electricity is generated, it means that the energy of the wind was deprived and converted into electricity. Supposing that the conversion efficiency from wind to electric power is 50%, the wind strength (= energy) corresponding to the second wind turbine is only 50% of the initial value left, and it is produced by the second wind turbine I can only expect half the power of the first windmill. In this way, when the wind turbine is laid out in line with the wind, wind power generation can not receive enough energy from the wind. Therefore, when arranging a windmill on the ground, the construction site is considered as much as possible so that the wind direction and windmill do not line up on a straight line.

However, at ocean, this phenomenon is greatly improved. Especially, in the vicinity of the equator where temperature and water temperature are high active convection of the atmosphere near the sea surface and the sky is actively occurring, and the movement of the wind is not only the horizontal direction but also the movement of the wind blowing from the top to the bottom also exists about. Therefore, more wind energy is supplied to the windmill placed on the ocean, and it is said that the power generation efficiency which is not comparable with the land is realized.

In other words, wind power generation on the land merely scrapes a part of the kinetic energy of the wind that flows near the surface of the earth, whereas offshore wind power generation is at the atmosphericTroposphereIt is possible to convert energy of electricity into electricity. The research team estimates that offshore wind power has the potential to generate three times the electric power of land wind power generation. If we were to construct a wind farm with an area of ​​2 million square kilometers on land, then we can not meet the "7 Tera watt-hours per year" required by China and the United States for the power that can be generated there. However, if wind power plants of the same area are constructed on the ocean, it is thought that they will have the capacity to supply electricity to other countries, while satisfying the demand of these two large electricity consuming countries I will.

World electricity consumption | electricity consumption | Enerdata
https://yearbook.enerdata.jp/electricity/electricity-domestic-consumption-data.html

In the future, it is certain that the electricity demand will further increase on the Earth, and we will not be dependent on fossil fuels and nuclear forever forever. Although it is offshore wind power generation that is going to collect expectations in such a situation, it is not necessarily all that is good. Converting the energy of the wind into electricity means that the movement of the wind surrounding the earth weakens or changes. The wind that circulates the earth greatly has the function of moving the heat of the atmosphere of the earth, but this movement is stagnant due to the weakening of the wind, the conventional climate model is affected, the global climate balance collapses It is also thought that climate change that did not predict will occur on a global scale.


Caldeira pointed out that "pulling out the power to support the civilization from the wind will bring problems." At the same time, however, it is also possible to reduce the negative dependence by lowering the dependency on offshore wind power generation, not making the power generation facilities too large, and further dispersing them at several points on the earth.

But it may be a problem of "budget" that really becomes a big challenge. Compared to the solid ground of the foundation, construction of a windmill on a watery ocean, building windmills with thousands to tens of thousands of unbreakable wind blows even more strongly than the ground can be quite costly, It will cost a lot to maintain that equipment. Whether we should advance research and development of offshore wind power generation after subtracting that cost seems to be necessary to watch the development of future technology. Of the offshore wind power generation projects that had been undertaken in Japan, there are things that were canceled because the wind situation (wind condition) and cost deviated far from the original assumption in the plan off the Ibaraki prefecture. Although it is premature to think that the same problem exists in all plans, it seems that offshore wind power generation is still at a stage where many things will come to be known.

Disadvantages of offshore wind power generation [offshore wind power generation navigation]
http://www.o-wp.net/demerit/

Canceling planned offshore wind power generation project, costs and wind conditions are out of expectation (1/2) - Smart Japan
http://www.itmedia.co.jp/smartjapan/articles/1701/13/news026.html