In 10 years, the Offshore Wind Accelerator (OWA) has run over 150 projects supporting innovations that have led to both a significant reduction in the cost of energy and risk, whilst making offshore operations safer. To mark this milestone in R&D collaboration, we have selected 10 high impact innovations to showcase the breadth and depth of the programme.
In order to make the most efficient use of the wind resource when developing large wind farms, the turbulence intensity needs to be measured and modelled to fully understand wake losses and predict the maximum array efficiency limit. More accurate turbulence intensity predictions allow unnecessary costs to be eliminated from the foundation design and to reduce uncertainty.
As next generation wind farms are developed further offshore, significant cost savings can be achieved by refining the foundation design and making the turbines more reliable by having a more accurate means of predicting the wind turbulence and fatigue loading.
The OWA ran a project which validated and refined the Frandsen model for turbulence intensity in large wind farms by comparing data collected from the model with turbulence intensity measurements extracted from the Rødsand II and Greater Gabbard datasets. This project resulted in increased confidence in the efficiency of the Frandsen model. These learnings were applied to the Beatrice project allowing SSE to refine the designs and increase the certainty of their turbulence predictions and fatigue loading.
Computational models are widely used for wake loss predictions to support wind farm planning. These models not only allow developers to understand the optimal design of projects, they also allow developers to justify the predicted revenues to investors and funders. In July 2015, the OWA published a journal article which showed that the default wake loss uncertainty of 50 per cent was unnecessarily high and it would be more appropriate to apply an uncertainty of 25 per cent or less. A reduced default wake loss uncertainty has now been accepted by a wide range of institutions, and have also been applied to the Beatrice project among many others which has had a significant positive impact on the financing costs.
Wake models are used during the development process to understand the likely yield from a wind farm. Ansys’ Windmodeller is an example of a wake model that is widely used by the industry to help understand the theoretical wind flow through wind farms. In practice, the application of models like Windmodeller varies by user, making the results inconsistent. In order to increase understanding of how best to apply the model and ensure it is used effectively to get the best results, the OWA developed a detailed guide to provide support for an effective and consistent approach to using these models, including Windmodeller, which was used on the Beatrice project.
The Offshore Transformer Module (OTM®) concept reduces an Offshore Platform (OSP) down to its bare essentials and places the substation components on smaller substructures. The solution removes the need for large heavy lift vessels to install the large OSP foundations and their topsides, and opens up the potential to utilise smaller and more cost-effective vessels. In 2015, the OWA launched a study to further investigate the benefits of the OTM® concept, and a project to support the market introduction of OTM® technology. The project investigated the engineering and regulatory challenges faced during design and refinement to allow a better industry understanding and acceptance of this cost saving solution.
The first two of these pioneering designs were designed and installed by STDL on the Beatrice project in 2018.
Development of offshore wind farms has led to the need for specialist vessels to transfer workforce and equipment safely to and from the turbines during both the construction and O&M phases. Performance characteristics of these vessels vary considerably, leading wind farm developers to consider the need for a better understanding of vessel performance, not only to improve the relationship between the charter rates of CTVs to their operational capabilities, but also to increase vessel availability in more challenging environmental conditions.
The P-plot method of recording vessel performance during transit and at the point of transfer will be carried out at Beatrice to monitor O&M vessels.
The ensuing research, run through the OWA, developed a standardised sea trial programme and subsequently undertook sea trials for a range of CTVs. This led to a better understanding of performance for a range of vessels, including how CTVs interact with inclined boat landings on turbines, as opposed to the standard vertical landings.
This article is part of 10 years, 10 innovations: A summary of the impact of the Offshore Wind Accelerator