Wind energy relies on windmills (also called wind turbines) to capture the wind energy. The formula for obtaining wind energy is:
P=0.37x10 - 4AV3
P represents power, the unit is kilowatts 〔KW〕
A represents the cross-sectional area of the windmill blade, the unit is meters [m]
V represents the average wind speed, the unit is meters per second [m/s] < /p>
It can be seen from the formula that in order to obtain greater wind power, a larger-sized windmill must be used to align the wind direction and receive wind with a higher average wind speed.
Wind direction and wind speed are important indicators of wind energy. Generally speaking, the wind direction refers to the total average (main direction) of all directions that have occurred within ten minutes, which is marked by sixteen directions (such as south-south-east, northwest-west). In addition to expressing the wind speed by [length/time], It can also be described by the scene of wind blowing in nature. This description is called Beaufort scale.
At present, meteorological observation stations observe wind speed eight times a day, and each time the average wind speed within 10 minutes represents the wind speed in the three hours; if you want to use wind power, you should conduct more detailed observations; and record it over a long period of time. Understand the maximum wind speeds and conditions under which turbulence occurs. If within 10 minutes there is an instantaneous wind speed greater than this average value of 5 meters/second, it is called a gust.
For general small wind power generation devices, the required starting wind speed is 3 meters/second and the rated wind speed is 20 meters/second. It will stop when encountering strong winds of 56 meters/second. When actually generating electricity, the wind turbine blade area Each square meter can only generate approximately 124W (average wind speed 10 meters/second).
The formula for calculating wind power cost per kilowatt hour is as follows:
1. LCOE = construction cost + operation and maintenance cost + power generation. When measuring the economic benefits of wind turbines, the unit cost of energy (cost of energy COE), that is, the cost per kilowatt-hour, is used as the evaluation index.
2. The unit’s kWh cost is the ratio of the total cost of the unit to the power generated.