Contributed by Pete O’Connell, Lead Project Manager, Mammoet
The drive to create greater amounts of renewable power from onshore wind farms is creating a new set of challenges, especially as developments move to more remote locations and turbines reach greater heights. This means that work to install these facilities is changing too, and demands seasoned expertise so that a flexible approach can be taken depending on the scope of a particular project.
The onshore wind challenges: height and size
Larger turbines generate more power, which is good news for the efficiency of wind farms.
But as hub heights reach ever higher so do the cranes required to install them, which in turn means larger-scale equipment. Wind farms must also choose from a smaller pool of cranes, given that there are fewer cranes above 175m.
Dealing with higher hub heights is not the only challenge created by larger turbines. The size and scale of components from longer, heavier blades to larger nacelles and tower sections must be accounted for in project methodologies.
Longer blades and heftier components aren’t just challenging to install but also to transport. The obstacles don’t end on public roads; it’s tough on site too. This translates to the need for wider site roads and larger, sturdier hardstands, escalating civil costs which heavy lifting and transport project partners must try and mitigate with clever selection of equipment.
The increase of turbine sizes in the search for ever higher productivity also means those larger cranes need to be moved between pads where turbines are constructed. The speed at which this can be done, when mobilization and demobilization of equipment such as crawler cranes can take days, can be a critical factor in how quickly turbines are installed and generating power.
Furthermore, the scale-up in turbine size and component dimensions is putting a strain on available equipment. Particularly for hub heights beyond 169m, there are very few cranes capable of meeting the demands.
Navigating remote wind farms
The industry is also venturing further out to more remote locations. For every extra mile, more roads, bridges, or tunnels may need modifications, not to mention the additional permitting involved. Heavy transportation partners must work hard to identify not simply the shortest route to the site but above all the most efficient in minimizing the number and scale of modifications to civil infrastructure.
Invaluable expertise from other projects
Ultimately, the logistics of setting up renewable energy infrastructure in a remote location is a specialized job. While local people can be trained for some tasks, certain aspects demand experienced hands.
Therefore, working with a specialist heavy lifting and transportation partner can reap dividends, especially as wind farms become more and more remote. Experience from other similar projects whether in the same part of the world or further afield can be invaluable in identifying where time can be saved, and turbines brought online sooner.
Mammoet’s solution at Kaban Wind Farm
Neoen’s Kaban Green Power Hub in Australia, a region renowned for its distinctive environmental conditions, has its own set of unique challenges – from dense fog to tricky terrain.
Here at Mammoet, we needed to overcome the challenges posed by the remote nature of the site, with narrow access roads and steep slopes, if we were to achieve the right levels of safety and operational efficiency, while also minimizing the project’s carbon footprint.
The scope of work included the offloading, preassembly, and main installation of 28 Vestas wind turbines. We assisted in the lifting and assembly of turbine components, including tower sections, nacelles, powertrains, hubs, and blades. Once assembled, these turbines stood at an impressive tip height of 226m.
Central to navigating this formidable task was the ability for us to select the right equipment from our extensive inventory.
Streamlining turbine construction
With efficient offloading and preassembly key factors in keeping components available for installation in a timely fashion, we explored options to offer an agile approach. A 700t capacity Terex Demag AC700 crane was selected for this scope, engineered to set up in a single optimal position, which enabled a two-stage offloading process with intermediate preassembly. This approach decreased the number of teams required on-site from three to two, and minimized crane movements needed between lifts, resulting in significant time and cost savings.
A much larger crane was needed to complete the installation of the huge turbines. A LG 1750SX, equipped with a 151m main boom and 12m fixed fly, was used to provide the required reach. Meeting the requirements of these high and powerful Vestas wind turbines, it lifted the powertrains, each weighing 92t, to a hub height of 149m.
A range of SPMT and multi-axle trailers were used to maneuver 400t of superlift counterweight at once, supporting the LG 1750X installation, and up to 280t of counterweight at once during on-site relocations. This method not only accelerated operations but also reduced the number of truck and trailer trips, ultimately minimizing the project’s carbon footprint.
In summation, the rewards of setting up wind farms in remote locations like Kaban are significant. It’s a journey of persistence, innovation, and collaboration. However, as the world grapples with climate change, these challenges aren’t deterrents; they’re calls to action.