As offshore wind farms move further into deeper waters, optimised foundations are key to help reduce uncertainty and minimising the Levelised Cost of Energy (LCoE).
Continuously increasing turbine sizes combined with challenging soil conditions necessitate accurate, robust and efficient design models to maximise the competitiveness of offshore wind energy in the future.
The Monopile has established itself as a standard foundation type in the current marketplace. However, conventional design models have proved unreliable and non-optimal. The industry has therefore commissioned intensive research efforts to develop improved design methodologies. These research projects have yielded significant advances, such as updated distributed soil-spring-models (e.g. PISA) and optimised macro-elements (e.g. RedWin).
Within the offshore market, NGI has been at the forefront of developing and implementing fit-for-purpose geotechnical models with direct application in industry projects. We have taken our knowledge from almost 50 years' experience of offshore foundation design to develop analysis tools tuned to the needs of dynamically-sensi- tive offshore wind structures.
These analysis tools are based on distributed springs and macro-elements, adapted to the design situation, i.e. ULS, SLS and FLS. The models are carefully calibrated with numerically-efficient Finite Element Analysis (FEA) models according to industry best practice. NGI's unique understanding of cyclic and dynamic soil behaviour combines our extensive numerical analysis capabilities with the world's largest independent advanced geotechnical laboratories. This feeds directly into the soil models used for FEA and the results of the analysis methods.
- ULS design ensures that overall pile dimensions are kept to a minimum to satisfy the operational loads whilst avoiding unnecessary material costs and installation risk
- SLS design requires understanding of the lifetime performance of the system to ensure that displacements and inclinations stay within the specified limits
- FLS design calls for efficient but accurate models that are easily included within integrated time-domain analyses and capture the non-linear dynamic response.
NGI's optimised monopile design solutions therefore ensure a streamlined approach which is tailored to the needs of the industry and is easily integrated within the overall design process to provide technical value without burdening the overall project timeframe. The design process is easily coupled with high quality site investigations, ground model development and the use of structural health monitoring for the installed support structures.
In this way, NGI provides a unique range of services for Next Generation Monopiles in the worldwide offshore wind market