Heavy lift company, Johnson Crane Hire has secured a long-term contract with Danish wind turbine manufacturer Vestas for its South African projects.
The 12-month contract entails finding and instituting appropriate heavy lift solutions for Vestas’ involvement in four wind farm projects throughout the Western and Eastern Cape.
Vestas is providing wind turbines to wind farm projects at Grahamstown, Saldanha, Great Kei Municipality, Tsitsikamma and Grassridge that were selected in the second round of the Renewable Energy IPP Procurement programme.
Lifting 27 turbines
Johnson Crane Hire’s involvement on the West Coast 1 project in Saldanha, which entailed executing the lifts for 27 of the 46 turbines, was completed at the beginning of March 2015.
The company was responsible for the heavy lift of each of the 80 metre high, 2MW capacity, V90 turbines, including the 96 ton nacelles and 13 ton blades, as well as for relocation of the crane components between each turbine pad.
The Chaba heavy lift contract in the Great Kei Municipality, adjacent to the N2 near Komga, commenced immediately after the finalisation of the West Coast 1 contract and was completed in April 2015.
This project involved the lifting of seven V112 3MW turbines, each with an installed height of 84 metres.
Cornelis Grotius says that typically for heavy lift solutions such as required by Vestas, Johnson Crane Hire would be contracted on a project by project basis. However, the company was able to offer a long-term sustainable heavy lifting solution to Vestas, which was accepted in September 2014.
“It is very rewarding to be working with a company like Vestas that has a footprint of 53,700 wind turbines worldwide, effectively reducing carbon emissions by over 60 million tons of CO2 every year.”
Grotius says that the benefits of the long-term lifting solution accrue to each of the parties. Vestas received preferential long-term contractual pricing, is also assured of constant service delivery levels in-between each of the four contracted projects.
While each project can proceed without delay as the crane, a Liebherr 750-ton LG1750 lattice boom truck mount crane, has been requisitioned for sole use at the Vestas wind farm sites.
Johnson Crane Hire benefits from the constant use of its crane over the 12-month period and the elimination of time-consuming renegotiations between contracts.
No need for civil works
The crane, the largest machine of its kind in South Africa, is a combination hydraulic/lattice machine mounted on rubber wheels. According to the company, the Liebherr LG 1750 design allows for easy relocation between sites with increased mobility on sites with varying terrain.
Grotius says that typically crawler cranes require extensive civil works to mobilise, but this is not the case as the crane’s truck mounted carrier and extendable outrigger base eliminates the necessity for this.
Grotius says that preparatory work for the two completed lifting projects was complex, with intricate lift design and planning being the order of the day.
“Since each installation was undertaken in an area chosen for its constant, consistent and high-speed winds, we had to carefully calculate the effect of the wind on the lifting of each wind turbine component.
“Extensive rigging studies and methodologies were required not only for the shipping, but also for the building and installation of the crane. Safety of all on site during the lifts was a primary concern”, he said.