Brown Hill Wind Farm (Hallet One)
Scope of Work
The Brown Hill Wind Farm is a 94.5 megawatt renewable energy project located some 220km north of Adelaide. This project comprised of 45, 2.1MW Wind Turbine Generators supplied by Suzlon Energy Australia under contract to AGL Energy Limited.
icubed consulting completed the detailed design and documentation of the Wind Turbine foundation system for the Brown Hill Wind Farm. Working closely with local civil engineering contractor, Built Environs and Coffey Geotechnics, an alternative high-performance rock-anchored footing system was developed and deployed on this project. The foundation design exploits the rocky ground conditions which prevail on the development site.
icubed consulting devised a high capacity rock anchor solution which was able to achieve the massive overturning resistance under operating and ultimate load conditions, using only one third of the concrete and reinforcement required in traditional gravity foundations.
Each rock anchor has an ultimate capacity of around 450 tonnes and is vertically stressed to lock the entire tower and foundation down to the ground with a combined force of over 2300 tonnes.
Horizontal post tensioning cables were adopted within the foundation cap to minimise the amount of conventional reinforcement, minimise bar congestion and simplify construction processes. The substantially reduced physical dimensions of the foundation resulted in large savings in excavation requirements. Typically a conventional foundation would require in excess of 1000 cubic meters of excavation, whereas the alternate design required only 150 cubic meters.
This foundation design achieved substantial time, cost and material savings, whilst improving the environmental performance through a reduced physical and carbon foot print. The foundations consume far less raw material and construction effort reducing CO2 cost by over 50t per unit. Significant productivity gains were achieved, such that the foundation works were effectively complete prior to the commencement of the intensive tower and turbine installation program. The project team of icubed consulting, Built Environs and Coffey Geotechnics has gone on to secure a further five projects in SA and NSW, including Hallett Two. These projects will comprise of 231 Turbines and an overall installed capacity of nearly 500MW.
Dates: July 2007 – December 2010
Disciplines: Detailed Design & Documentation
Sector: Renewable Energy