Owner: Eskom Resources & Strategy

Purpose:  Research & Demonstration

Location: Klipheuwel, 15 km north of Durbanville, close to Slent Rd crossing with Stellenbosch-Malmesbury Rd

Unit
Rated Power

Vestas V66
1.75 MW

Vestas V47
660 kW

Jeumont J48
750 kW

Rotor

Diameter

66 m

47 m

48 m

Blade Number x Length

3 x 32 m

3 x 23 m

3 x 23 m

Swept area

3 421 m²

1 735 m²

1 810 m²

Speed revolution

21.3 rpm

28.5 rpm

Variable

Operational interval

10.5 - 24.5 rpm

28.5 - 30 rpm

7-26 rpm

Tip speed

130.6 - 265 - 305 km/h

252.5 - 265.8 km/h

63 - 235 km/h

Rotor orientation

Horizontal, face wind

Horizontal, face wind

Horizontal, face wind

Power regulation

Pitch/OptiSpeed™

Pitch/OptiSlip^®

Stall Aerodynamic uncoupling

Air brake

Feathered

Feathered

Aerodynamic Tip-brake

Disc brake

Hydraulic controlled

Hydraulic controlled

Hydraulic controlled

Tower

John Thompson - Bellville

Vestas Imported

Jeumont Imported

Hub height (approx)

60 (Other  67, 78 m)

40 (Other 45, 50, 55 m)

46 m

Foundation (approx)

~ 500 ton

~ 240 ton

~ 450 ton

Operational data

Cut-in wind speed

4 m/s (14.4 km/h)
Self start

4 m/s (self start at ave wind speed of ~4.5 m/s)

3 m/s (10.8 km/h)

Nominal wind speed

16 m/s (57.6 km/h)

15 m/s (54 km/h)

13.5 m/s (48.6 km/h)

Stop wind speed

25 m/s (90 km/h)

25 m/s (90 km/h)

25 m/s (90 km/h)

Maximum 5 s gust

Class 1: 70 m/s (252 km/h)

Class 1: 70 m/s

Class 2: 55 m/s (198 km/h)

Generator

Type

Asynchronous Induction Generator
(radial flux cylindrical)
with OptiSpeed™

Asynchronous Induction Generator
(radial flux cylindrical)
 with OptiSlip®

 Synchronous generator with permanent magnets,
(axial flux discoidal)
with IGBT electronic converter with vectorial control system

Nominal output

1750 kW

660 kW

750 kW

Operational data

50 Hz; 690 V

50 Hz; 690 V

50 Hz; 690 V (Grid)

Synchronous speed

1,515 - 1,650 rpm

900 V (Gen)

Gearbox

Type

1 planet step
2-step parallel axle gears

Planet/parallel axles

None (Direct - gearless)

Control 

Type

Microprocessor - based monitoring of all turbine fuctions with the option of remote monitoring. Output regulation and optimisation via OptiSpeed™ and OptiTip® pitch regulation.

Microprocessor - based control of all turbine functions with the option of remote monitoring.

OptiSlip® output regulation and OptiTip® pitch regulation of the blades.

Microprocessor

IGBT electronic converter
(with DC-bus)

Weight 

Tower (hub height)

60 m / 100 t (3 sections)
Various sizes available

40 m / 32 t (2 sections)
Various sizes available

46 m / 40 t (2 sections)
Various sizes available

Nacelle

57 t

20.4 t

30 t

Rotor

23 t

7.2 t

9 t

Total

180 t

60 t

80 t

Additional info

Khoebaha Sousoa

Krotoa

Khamisoa

Sousa adopted Jan van Riebeeck as a son on 29 Sept 1660.

Father of the nation at the time of transformation (Last emporer of Hottentot lands)

Transformation Goddess
Daughter of Wind Goddess

The Wind Goddess

Approximate cost

R18 million

R8 million

R12 million

Date Commissioned

13-Dec-02

17-Aug-02

20-Feb-03

Contractor / Tender

Vestas / Partners International Technologies

Intens Lesedi

Civil work by:

WBHO (also road)

Summit Projects

Installation by:

Vestas & Vanguard

Jeumont & Summit Projects

Crane from:

Johnson Cranes: 550 t

Target Cranes: 175 t

Ashley: 1000 t

www.sabregen.co.za

www.windpower.org

www.vestas.com

www.jeumont-framatome.com

Power max (W) = 0.5 x air density x Rotor sweep area x Wind Speed^3 x Cp (0.2-0.4 for slow speed multiple blade)