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| How much power can the wind turbine generate in a circle when it rotates so slow |
| Release time:2023-02-09 10:22:30| Viewed： |
In Zhejiang, there are various wind farms
Jiaxing Jianshan Onshore Wind Farm
Taizhou Dachen Island Offshore Wind Farm
Linhai Kuocangshan Wind Farm
These wind farms provide a steady stream of green power for local economic development. It is believed that many young friends have had such doubts: the windmill rotates so slowly, and how many kilowatt-hours can it produce in one circle?
Let's start with the power generation principle of wind turbines.
The wind turbine generator unit is composed of impeller, engine room, tower and other basic components. Its power generation principle is very simple: the unit uses the wind to drive the wheel of the windmill to rotate, and converts the wind energy into mechanical energy. The generator then converts the mechanical energy into electrical energy, and then the electrical energy is transmitted to the booster station of the wind farm through the power collection line. After boosting, it is transmitted to the power grid, and can become clean wind power for thousands of households.
Kuocangshan wind turbine But a wind farm is composed of dozens or even hundreds of windmills. How do so many windmills work?
Each windmill is controlled by the main control room, which is the "central brain" of the wind farm. The staff responsible for the operation of the wind turbine unit monitors 24 hours a day to ensure the safety and health of the windmill.
So how many kilowatt-hours can the windmill leaf generate when it turns around?
Take the 1500 kW fan unit as an example, the blade of the unit is about 35 meters long (about 12 floors high). Each rotation of the wind turbine takes about 4-5 seconds (but the blade tip speed can reach more than 280 kilometers per hour, which is comparable to the speed of high-speed rail), and can generate about 1.4 kilowatt-hours of electricity. Under normal full power conditions, one day's power generation can be used by 15 households for one year. Such a wind turbine can reduce 3000 tons of carbon dioxide, 15 tons of sulfur dioxide and 9 tons of nitrogen dioxide annually.
Like the wind farm in the western mountain area of Huangyan, the total land area of the project is 1.6727 hectares, and 28 wind turbines with a unit capacity of 1500 kW are installed. The total installed capacity is 42000 kW, and the annual on-grid power can reach 84.14 million kWh.
Is wind power generation as strong as possible?
According to the law of conservation of energy, it is true that the higher the wind speed, the more electric energy will be provided. But when the wind speed reaches a certain value, our wind energy converter will be damaged due to excessive intensity. In fact, the power generation does not depend on the blade speed.
Because there is a device similar to the automobile gearbox in the wind turbine generator unit, for example, if the gearbox is shifted to the first gear, even though the blade speed is very fast (equivalent to the full throttle pedal), the transmission through the gearbox to the generator unit is still relatively constant low speed (equivalent to the car or not running fast). With such a device, the direction change also plays a protective role. In the case of constant blade speed, the power will increase with the increase of blade force. The larger the blade of the fan, the greater the power, and the more the corresponding power generation.
So the wind will not be obedient and only blow in one direction?
Don't worry, the head of the wind turbine is integrated with a sensor and a yaw system. Once the wind vane and anemometer collect the wind direction and wind speed changes, the yaw system will urge the yaw motor to adjust the position of the engine room, so that it can smoothly align with the wind direction and maximize the efficiency of using wind energy.
Wind power can be divided into onshore and offshore
Wind power is also subdivided into onshore wind power and offshore wind power. Such as Huangyan Bubao Mountain, Linhai Kuocang Mountain and Wenling Donghai Pond are onshore wind farms, while Jiaojiang Dachen Island Wind Farm and Yuhuan Kexiao Wind Farm are typical offshore wind farms.
Huangyan Youneng Wind Farm located on the ridge of Dasiji Mountain
Wenzhou Nanji Island Offshore Wind Farm
There are great differences in construction costs between the two. Generally speaking, the construction cost of offshore wind farms is twice that of onshore wind farms, and the operation and maintenance cost is 2-4 times that of onshore wind farms. This is mainly due to the poor offshore construction conditions and high construction difficulty, as well as the fact that the wind power in Shanghai is far away from the shore, typhoon, storm surge and other adverse sea conditions will also have a great impact on the operation and maintenance of wind power.
Why should we continue to develop wind power offshore?
The sea is vast and has abundant wind energy resources. The offshore wind power generation has high utilization hours, does not occupy land, does not consume water resources, and is suitable for large-scale development. The power generation efficiency is generally 20% - 40% higher than that of onshore wind power. In other words, potential is "leverage". Wind power has great potential to achieve carbon peak.
Zhoushan Liuheng Offshore Wind Farm
Wind energy is renewable energy and very environmentally friendly. Moreover, wind energy facilities have little impact on the ecological environment. Although the initial investment is large, compared with hydropower and thermal power, the later maintenance and management costs are extremely low, and it is one of the most mature, large-scale development conditions and commercialized power generation methods in the field of new energy at present.
However, wind is an intermittent renewable energy. Its power changes greatly in a short time, but its power is relatively stable in a long time. This makes wind power generation unable to increase or decrease power generation according to demand and cannot be used as a base load power source. Therefore, wind power must be used together with other power sources or storage facilities to provide stable power. With the increase of wind power generation in the region, more conventional energy such as thermal power generation and nuclear power generation may be needed as backup, or the power grid may be upgraded.
However, power management technology can be used to solve these problems, such as dispatching different renewable energy and generating units with different geographical distribution, importing and exporting power to neighboring areas, and storing energy. Therefore, at present, power grid companies are exploring how to achieve large-scale consumption of new energy.
State Grid Zhejiang Electric Power once proposed to build a multi-element and high-flexibility grid in the form of energy internet, and proposed to achieve efficient interaction of "source network load storage" and solve the problem of new energy consumption by accelerating the construction of energy storage. With the "30 · 60 target" proposed, the development of new energy is encouraged at the national level, which provides a good opportunity for large-scale development of wind power. |
