Formula Used
Swept Area: A = π × (D / 2)²
Wind Power: P = 0.5 × ρ × A × V³
Capacity Factor AEP: AEP = Rated Power × Hours × Capacity Factor
Net AEP: Net AEP = Gross AEP × Availability × Remaining Loss Factors
Full Load Hours: Full Load Hours = Net AEP / Rated Power
How to Use This Calculator
Choose a calculation method first. Use the capacity factor method when you already know the expected capacity factor. Use the power curve method when you want to estimate output from turbine speed limits, average wind speed, and Weibull behavior.
Enter rotor diameter, rated power, average wind speed, air density, losses, and availability. Then press the calculate button. The result appears above the form and below the header. You can export the result as CSV or print it as a PDF report.
Annual Energy Production Wind Turbine Guide
Annual energy production shows how much electricity a wind turbine can produce during one year. It is usually expressed in kilowatt hours, megawatt hours, or gigawatt hours. This value is more useful than rated power alone. Rated power only shows maximum output under strong wind. Yearly production shows expected real energy.
Why Wind Speed Matters
Wind speed has a strong effect on production. The available wind power follows the cube of wind speed. A small increase in wind can create a large gain in energy. This is why accurate wind measurement is important before selecting a turbine. Hub height, terrain, trees, buildings, and seasonal changes all affect the final estimate.
Rotor Area and Turbine Size
The rotor captures moving air. A larger rotor sweeps more area and can collect more energy. The swept area is based on the rotor diameter. Modern turbines often use larger rotors to improve low wind performance. However, the generator, tower, controls, and blade design also matter.
Losses and Availability
No wind project converts every available kilowatt into delivered electricity. Wake losses occur when turbines disturb each other. Electrical losses happen in cables, transformers, and converters. Other losses may include icing, curtailment, turbulence, blade soiling, and maintenance downtime. Availability measures how often the turbine is ready to operate. Higher availability improves annual energy.
Capacity Factor Meaning
Capacity factor compares actual annual energy with the energy produced at full rated power all year. A turbine with a high capacity factor uses its rated capacity more effectively. Good wind sites may have strong values. Low wind sites may need larger rotors or smaller generators.
Using the Result
This calculator helps compare turbine options, site assumptions, and loss cases. It can support early planning, classroom work, feasibility studies, and quick project checks. The result is an estimate, not a certified energy assessment. For investment decisions, use measured wind data, certified power curves, and professional site modeling.
FAQs
What is annual energy production?
Annual energy production is the electricity a wind turbine produces in one year. It is commonly measured in kWh, MWh, or GWh. It gives a practical view of yearly output.
Why is rated power not enough?
Rated power shows maximum output at rated wind speed. Real winds change often. Annual energy production includes time, losses, wind behavior, and operating availability.
What is capacity factor?
Capacity factor is actual yearly energy divided by maximum possible yearly energy. It shows how effectively the turbine uses its rated power over the year.
Which wind speed should I enter?
Use the long term average wind speed at hub height. Do not use ground level wind speed. Hub height speed gives a better production estimate.
What does Weibull shape factor mean?
The Weibull shape factor describes wind distribution. A value near two is common for many sites. Higher or lower values change how often useful wind speeds occur.
Why include wake loss?
Wake loss happens when one turbine reduces wind energy behind it. It is important in wind farms. A single isolated turbine may have low wake loss.
Can this calculator replace a wind study?
No. It is best for planning and comparison. A bankable wind project needs measured wind data, detailed terrain modeling, and certified turbine power curves.
What is full load hours?
Full load hours convert annual energy into equivalent rated operation time. It equals net annual energy divided by rated power. It helps compare projects quickly.