Karreebosch Wind Farm, South Africa, located near Sutherland in the Northern Cape, has achieved a significant construction milestone with the successful erection of its first wind turbine. The 3-blade rotor was successfully lifted in one piece and mounted onto the nacelle on 4 March.

The Karreebosch Wind Farm will comprise 25 wind turbines installed across a 3 000 ha project area extending approximately 25 km from north to south near Sutherland. Each turbine has a rated capacity of 6.0 MW and uses permanent magnet direct drive technology to improve efficiency and reduce mechanical complexity. Once operational, the wind farm will supply approximately 460 GWh of renewable electricity annually to Northam’s mining operations under a 20-year power purchase agreement.

Developed by Cennergi Holdings and G7 Renewable Energies, the project represents continued investment in large-scale renewable energy infrastructure in South Africa.

Precision Engineering in Turbine Installation

Wind turbine erection is a tightly sequenced engineering process requiring coordination across multiple technical disciplines. At Karreebosch, installation progressed in three sequential steps:

1. Assembly of four individual tower sections to a 100-metre hub height.

2. Installation of the nacelle and ring generator.

3. Execution of the star lift - the installation of the fully assembled rotor (hub and blades).

During the star lift, the hub and three blades are pre-assembled at ground level and lifted as a single unit using heavy-lift crane systems before being secured to the nacelle at hub height. This operation demands narrow wind-speed tolerances, precision rigging design, and strict safety governance.

Turbine specifications:

• Rated Capacity: 6.0 MW per turbine
• Tower Height: 100 m
• Rotor Diameter: 165 m

The component weights underscore the scale of the operation:

• Generator: 117 tons
• Nacelle: 43 tons
• Hub: 57,3 tons
• Weight of the star (3 blades and hub):  128,4 tons

Each wind turbine stands on a foundation approximately 20 metres wide and 4 to 5 metres deep, requiring roughly 600 cubic metres of concrete.

The project also incorporates environmental mitigation measures, including painted turbine blades to improve visibility for birds. The team is further investigating an AI-based monitoring system using cameras to detect sensitive bird species and automatically curtail turbine operation when required.

Dr Kilian Hagemann, Chief Executive Officer of G7 Renewable Energies, said:

“The star lift represents one of the most technically demanding moments in wind farm construction. It signals that planning, engineering, logistics, and safety systems have aligned successfully. Milestones such as the star lift demonstrate the engineering capability being deployed locally.”

The star lift reflects a successful convergence across project delivery interfaces, including:

• Civil and foundation engineering
• Heavy-haul transportation logistics
• Crane engineering and lifting studies
• Weather-risk planning
• Multi-contractor execution management

“Seeing a 165 m rotor assembled in the sky is a reminder of what coordinated engineering effort can deliver. Reaching this milestone demonstrates the strength of collaboration between our project partners, contractors and specialist teams. Credit goes to the OEM specialists, safety personnel and Karreebosch site management for achieving this milestone with discipline and precision,” said Hagemann.

Construction of the remaining turbines will continue through 2026, with commissioning scheduled thereafter.