The gentle giants that spin in the wind, have become the norm to see over miles and miles of land across South Africa and the world. Using the wind as a renewable energy source just makes sense and these large wind turbines have been designed to maximise the amount of wind available and turn it into energy that we can use in our homes.
Many of us wonder though just how do they put wind turbines up? How are these huge spinning goliaths installed and how do they get such a large piece of machinery to stand upright and function?
Wind turbine installation and the transportation of the tower sections to the wind farm is a specialist service we, at Concord Cranes, offer. We’ve put together a wind turbine installation guide for the curious out there.
What is a wind turbine?
Let’s understand firstly, what wind turbines actually are. According to Wikipedia, a wind turbine or wind energy converter, converts kinetic energy from the wind into electrical energy for human use. Many countries, including South Africa, are using wind farms as a “source of renewable energy to reduce their reliance on fossil fuels.”
There are small turbines that generate just enough energy to power a battery or much larger ones that generate huge amounts of energy for a nation’s power supply. In South Africa, the large turbines can range between 80-114m in height. Chester Rawstron, Concord Cranes’ Sales Manager for the Eastern Cape, says that there is talk of these turbine heights increasing significantly as they are looking at developing farms with a greater output per turbine. “In 2024 we might see turbines 170m high being installed with blade lengths of 80m plus” he says.
How many parts do wind turbines consist of?
One large wind turbine consists of four or five tower sections, a nacelle or generator, and the hub which is connected to three rotor blades. Before you can begin to fit these parts together to create one turbine, these large parts need to first be expertly transported from their port of entry (having been shipped from the manufacturer) to the wind farm site.
“Concord Cranes is one of the leading wind turbine installation companies in SA and we’ve the secured a contract to transport a number of large blades from Coega to Golden Valley in the Eastern Cape. We’ve been involved in the transport of blades and other components to multiple other wind farms in South Africa over the past 7 years too” adds Chester.
The turbine components have to be loaded and offloaded using large cranes and the abnormal vehicles then create the road freight link between port and site. “All the main components of a turbine are considered abnormal loads due to their weight and size. Therefore, we use very specialised trailers to ensure that the weight is distributed correctly, and the load size does not exceed the abnormal load restrictions put in place. These restrictions are put in place by the Department of Transport,” he adds.
How are wind turbines installed?
The components of the wind turbines arrive on site in the correct lifting order to increase efficiency and to assist with traffic accommodation on site as the space on site is very limited.
“At Concord Cranes, we begin the installation by tandem lifting the tower sections from a horizontal position to a vertical position using a “tip & tailing” method. We use a smaller crane for this job as only one or two parts need to be positioned for the tower” says Chester. This is the “pre-population” process and by using a smaller crane, it allows Concord Cranes the ability to free up the larger main crane for the heavy-lifting part that comes next.
After the tower sections are installed, the main crane hoists and positions the nacelle. Once the nacelle is in place, the main crane as well as a secondary crane will assemble the rotor on the hardstand. Once the rotor is assembled, the cranes will “tip & tail” the rotor and attach it to the hub at the top of the turbine. The team of turbine technicians are responsible for ensuring that the components are attached together correctly.
How many cranes are used to install a turbine?
According to Chester, two cranes are needed for the “pre-population” phase. “We usually use a 130 tonne crane as well as a 550 tonne crane for this phase” adds Chester. “When it comes to the main lift and the nacelle and rotor installation, we make use of a 130 tonne mobile crane crane as well as the big 750 tonne lattice boom crane” he says.
From start to finish, it usually takes approximately three days to install a wind turbine – a small amount of time for a piece of design genius that will be able to generate electricity for consumption for a lifetime.
To find out more about wind turbine installation or the services offered by Concord Cranes – including mobile crane hire,heavy lift, turnkey solutions and rigging services – call 011 805 8071 or email us at email@example.com