6.4 KiB
6.4 KiB
4. Horizontal Wind Turbine (HAWT) Solution and Comparison
Example: Commercial HAWT (ManoMano)
- Product: 800W, 6-blade HAWT (link)
- Rotor Diameter: ~1.05m (area ≈ 0.87 m²)
- Rated Power: 800W (at high wind speeds, e.g., 12-15 m/s)
- Cut-in Wind Speed: 1 m/s (starts turning)
- Nominal Voltage: 12/24V
Realistic Power Output Calculation
- At 1.5m height: Wind speed is still low (see VAWT section)
- Average wind speed used: Same as VAWT, 3.3 m/s
- HAWT efficiency: Typically 30-35% (use 30% for estimate)
Power Formula
P = 0.5 \times \rho \times A \times v^3 \times \text{efficiency}
Where:
A= 0.87 m²v= monthly average wind speed (see VAWT table)\rho= 1.225 kg/m³- Efficiency = 0.30
Monthly Power Output Table
| Month | v (m/s) | P_avg (W) | kWh/month |
|---|---|---|---|
| January | 4.0 | 10.3 | 7.7 |
| February | 4.0 | 10.3 | 7.0 |
| March | 3.8 | 8.8 | 6.5 |
| April | 3.5 | 6.9 | 5.0 |
| May | 3.2 | 5.2 | 3.9 |
| June | 3.0 | 4.3 | 3.1 |
| July | 2.8 | 3.5 | 2.6 |
| August | 2.8 | 3.5 | 2.6 |
| September | 3.0 | 4.3 | 3.1 |
| October | 3.3 | 5.4 | 4.1 |
| November | 3.6 | 7.3 | 5.2 |
| December | 3.9 | 8.5 | 6.3 |
Annual total: ~57 kWh/year
Comparison: VAWT vs HAWT
| Type | Area (m²) | Efficiency | Annual Energy (kWh) | Pros | Cons |
|---|---|---|---|---|---|
| VAWT | 1.0 | 25% | ~54 | Simple, omni-directional, easy to build | Lower efficiency, less power at low height |
| HAWT | 0.87 | 30% | ~57 | Higher efficiency, more power at same wind | Needs to face wind, more complex, needs tail/yaw |
- Both types at 1.5m height produce similar (low) annual energy due to low wind speed.
- HAWT is slightly more efficient, but complexity and need to face wind are drawbacks.
- Commercial 800W HAWT will only reach rated power in very strong winds (rare at 1.5m).
Recommendations
- For learning and experimentation, both types are valid.
- For best results, try to raise the turbine higher (wind speed increases rapidly with height).
- Use data logging to compare real output with theoretical predictions.
- Consider safety and local regulations for both types.
Additional References
Wind Turbine Experiment in Plounéventer, France (29400)
1. Estimating Wind Power Output
Key Parameters
- Location: Plounéventer, France (29400)
- Turbine Type: Vertical Axis Wind Turbine (VAWT)
- Height: 1.5 meters above ground
- Swept Area: 1 m²
- Field: Open, unobstructed
Wind Resource Estimation
- Average wind speed at 10m in Plounéventer: ~5.5 m/s (source: wind resource maps)
- At 1.5m height: Wind speed is lower due to ground friction. Estimate: ~60% of 10m value ≈ 3.3 m/s
Power Calculation Formula
Theoretical wind power:
P = \frac{1}{2} \cdot \rho \cdot A \cdot v^3
Where:
P= Power (W)\rho= Air density (1.225 kg/m³)A= Swept area (1 m²)v= Wind speed (m/s)
Turbine efficiency (Betz limit): Max 59%, but real VAWT: 20-30%. Use 25% for estimate.
Monthly Wind Speed Estimates
| Month | Avg Wind Speed (m/s) |
|---|---|
| January | 4.0 |
| February | 4.0 |
| March | 3.8 |
| April | 3.5 |
| May | 3.2 |
| June | 3.0 |
| July | 2.8 |
| August | 2.8 |
| September | 3.0 |
| October | 3.3 |
| November | 3.6 |
| December | 3.9 |
Monthly Power Output Calculation
For each month:
P_{avg} = 0.5 \times 1.225 \times 1 \times v^3 \times 0.25
| Month | v (m/s) | P_avg (W) | kWh/month |
|---|---|---|---|
| January | 4.0 | 9.8 | 7.3 |
| February | 4.0 | 9.8 | 6.6 |
| March | 3.8 | 8.4 | 6.2 |
| April | 3.5 | 6.6 | 4.8 |
| May | 3.2 | 5.0 | 3.7 |
| June | 3.0 | 4.1 | 3.0 |
| July | 2.8 | 3.3 | 2.5 |
| August | 2.8 | 3.3 | 2.5 |
| September | 3.0 | 4.1 | 3.0 |
| October | 3.3 | 5.2 | 3.9 |
| November | 3.6 | 7.0 | 5.0 |
| December | 3.9 | 8.1 | 6.0 |
Annual total: ~54 kWh/year
2. Best Practices for Your Experiment
A. Turbine Design
- Use a simple, robust VAWT design (e.g., Savonius or Darrieus)
- Ensure the structure is stable and safe at 1.5m height
- Use lightweight, weather-resistant materials
B. Site Selection
- Place turbine in the most open, unobstructed area
- Avoid trees, buildings, or other windbreaks within 20m
C. Measurement & Data Logging
- Use an anemometer at 1.5m to log real wind speeds
- Install a wattmeter or data logger to record power output
- Record data at least hourly for best results
D. Safety & Legal
- Ensure the installation is secure and not a hazard
- Check local regulations for small wind turbines
E. Optimization
- Test different blade shapes and angles
- Compare results with theoretical predictions
- Try raising the turbine (if possible) to see the effect on output
3. Conclusion
- At 1.5m, wind speeds are modest, so expect low power output (max ~10W, average much less)
- Annual energy: ~54 kWh (best case)
- Main value: learning about wind energy, data collection, and optimization