Dynamic analysis to reduce the cost for fixed offshore wind energy turbines

Abstract

Offshore wind energy is the most promising marine renewable energy. To harness this type of energy, offshore wind farms are required. The main challenge in developing offshore wind energy is its high cost, necessitating studies to significantly reduce the cost. This study focuses on the optimization of their foundations, which account for over one third of the total cost. Current engineering practices rely on static analysis to calculate the responses of offshore wind turbines under extreme wave excitations, covering inherent uncertainty with a safety factor, often leading to excessively conservative designs. The physical processes associated with offshore wind turbine dynamics under extreme conditions - particularly in breaking waves - remain unclear, leading to overly conservative designs. To better understand the complex physical processes and explore the potential to reduce cost, a series of dynamic analyses is conducted here. The required monopile diameter based on dynamic analysis is found to be only three quarters of that from static analysis, potentially reducing steel consumption by 50 % and significantly lowering costs.