The global offshore wind industry has accelerated the steady pace of the global pandemic, with industry investments growing and offshore wind turbine manufacturers competing to see who will build a larger turbine. With offshore wind turbines, the bigger the better, Rystad said recently.
Wind turbine manufacturer Siemens Gamesa in May 2020 announced that it was working on the development of wind turbines with a capacity of up to 15 MW and a rotor of 222 meters – The the world’s largest under construction. The prototype should be ready in 2021, with commercially available turbines in 2024. The giant Siemens Gamesa turbines have already been ordered – conditionally – for projects in Taiwan and the USA
GE, the company behind the world’s largest wind turbine in operation, Haliade X – the prototype in Rotterdam – which has been spinning since the end of 2019 – recently improved this same turbine, from 12 MW to 13 MW. The improved 13 MW Haliade-X will continue to feature blades 107 meters long and a rotor of 220 meters.
In addition, GE just a month ago signed a contract to deliver the Haliade-X 14 MW wind turbines for the Dogger Bank C offshore wind farm in the UK. This will mark the first time that these turbines will be installed in any project worldwide.
So, with offshore wind turbines getting bigger and bigger, Offshore Engineer TV’s Greg Trauthwein recently interviewed Philip Lewis, Research Director, World Energy Reports, author of “Outlook for Offshore WInd Power, the Frontier of Future Energy”, to learn what larger turbines mean for the offshore wind industry and offshore wind installation contractors. In short, larger turbines require larger installation machines and larger vessels.
Lewis said: “We now have a series of projects to be installed from now until the mid-decade with turbines up to 14 MW. The main vessels used to install turbines are the wind turbine installation or WTIV vessels. The demand is driven by the number of turbines to be installed and the size of the turbines. “
WER expects more than 77 GW of new offshore wind capacity to start operating between now and 2025, requiring the installation of an average of more than 1,400 turbines per year.
But what about the size of the turbine?
“Turbine sizes have evolved rapidly […] but what does it really mean? Well, larger turbines mean large areas swept by larger rotor diameters, “explains Lewis.
“Larger rotor diameters require higher hubs, in which heavier nacelles sit to turn this wind energy into electrical. How wind turbine installation ships are raised to create stable platforms for installing the turbine and reduce requirements of crane reach, turbines up to 10 MW generally require elevation capacity above the deck height of more than 90 meters, with a capacity of not less than 800 tons.
“When looking at a 12-14 MW turbine, minimum lifting heights of 120 meters and more than 1,200 tons are required. And the next generation of ships is designed to lift more than 150 meters above the deck and more than 1,500 tons, ”he says.
According to Lewis, to date, more than 115 vessels – excluding support vessels – have been involved in the installation of wind turbines and their monopiles and jackets.
However, these were not the giant 14 MW + turbines of the future. These turbines require larger vessels and, although there are not many vessels currently capable of handling such turbines, the installation of offshore wind energy contractors are working on it.
“We only have two WTIVs active today that can already lift turbines over 14 MW or have confirmed upgrade plans to do so. There are 5 more under construction and 7 as options with a patio or project,” said Lewis.
“In World Energy Reports, we see the supply side for the larger wind turbine installation vessel segment growing from 8 vessels today to 28 in the coming years,” he adds.
Where will the growing WTIV fleet be built and deployed? Who will benefit most from the construction activity? What are the effects on local content restrictions in some countries, such as Japan and the USA? What are some of the largest ships ordered to transport and install the largest offshore wind foundations? Watch the full interview above for answers to these questions.