Offshore wind power or offshore wind energy is the generation of electricity through wind farms in bodies of water, usually at sea. There are higher wind speeds offshore than on land, so offshore farms generate more electricity per amount of capacity installed. Offshore wind farms are also less controversial than those on land, as they have less impact on people and the landscape.
Unlike the typical use of the term “offshore” in the marine industry, offshore wind power includes inshore water areas such as lakes, fjords, and sheltered coastal areas as well as deeper-water areas. Most offshore wind farms employ fixed-foundation wind turbines in relatively shallow water. As of 2020, floating wind turbines for deeper waters were in the early phase of development and deployment.
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Onshore Component Management
Except for the semi-submersible and TLP FWTs mentioned above, most OWTs require an offshore assembly of wind turbine components after being transported to the site. The number of offshore lifts depends on factors like wind turbine design, lifting equipment, sea conditions, and capacities of transport and installation vessels. For example, although an increased number of pre-assembled pieces reduces the number of offshore lifts, efficient use of the deck space of the transport vessel may be prevented, and large-capacity cranes may be required during the offshore construction consequently. These methods differ because of the number of pre-assembled components. All methods have been applied to installing OWFs in Europe and pertinent works can be found.
There are two onshore strategy definitions; “overall installation” and “split installation” as the two main categories. This definition indiscriminately places most methods under the “split installation” category. The trend is that more OWTs are assembled in a “split” manner because of the growing wind turbine sizes. The onshore pre-construction schedule allows us to stage, prep, and ready as much of the OWT as possible and lower the overall project costs.
As with most pre-assembly processes, the more planning, staging, and pre-construction you can do to an OWT the better. Using an onshore stable environment leads to quicker and safer assembly. This ultimately helps to increase the speed of installation and decrease cost overruns. Our deep understanding of procurement, planning, project management, and installation of onshore wind energy allows us to give you a tried, trusted, and true partner to help deliver your offshore wind project on time and on budget.
Heavy Equipment Management & Procurement
Installation vessels are involved in any OWT installations. Vessels are selected based on reasons including market availability, budget for installation tasks, and wind turbine technologies, e.g., size and number of components. Different types of installation vessels can be used in an OWF development (see lists a brief description of representative vessels below). Among them, tugboats are the most economical and are often used for towing non-self-propelled barges or floating foundations. A tugboat maneuvers other vessels by pushing or pulling them either by direct contact or by means of a tow line.
Heavy lift cargo vessels feature large cargo areas which ensure the vessels carry heavy modular components to suit specific project requirements.
As lifting operations require cranes with good capacities, crane barges and jack-up barges are widely used to lift pre-assembled wind turbines or support structures during installations. Originally used in the offshore oil and gas industry, a medium-sized jack-up barge may have a hull length of 60–80 m. Jackup barges of old generations have mooring systems, and it is necessary to have forecasts of wind and wave directions prior to installations in order to moor the vessel in a safe position relative to the OWT. Another downside of these vessels is that the crane height and crane capacity are inadequate for MW-sized OWTs. To meet this end, purpose-built jack-up vessels were constructed in the past decade. Compared to the older counterparts, these vessels are often in excess of 100 m in hull length, less susceptible to weather conditions, and are equipped with dynamic positioning systems. The large deck spaces make it possible for them to transport and install several OWTs in one trip. Although the day rate is higher, the offshore wind energy sector sees a huge demand for such specialized vessels.
Qualified Technical Manpower Supply
Teamwork has never been easy—but in recent years it has become much more complex. And the trends that make it more difficult seem likely to continue, as teams become increasingly global, virtual, and project-driven. We take a systematic approach to analyzing how well our team is set up to succeed—and identifying where improvements are needed. This makes all the difference in the world. We have a large percentage of repeat hires, who are mature and experienced in the wind energy sector. Experience and repeat hires lead to greater trust, safety, knowledge, and the ability to pivot on projects.