The increasing deployment of Offshore Wind Turbines (OWTs) necessitates larger steel monopiles, whose design currently includes additional steel to account for fatigue damage during installation. Traditional contact-based sensors, such as strain gauges and accelerometers, are challenging to deploy in offshore environments and are susceptible to damage under high stress. To overcome these limitations, a novel non-contact sensor system has been developed, utilizing the magnetomechanical effect to measure strain and an optical method to measure velocity. This paper presents the results of a test series using a full-scale impact hammer on a thin-walled steel pile, comparing the new system’s performance to a conventional Pile Driving Analyzer (PDA). Sources of error in the non-contact sensor measurements were identified, and post-processing techniques were applied to obtain acceptable time signals. Despite some residual errors, the system effectively captured strain and velocity behaviour. These findings demonstrate the feasibility of contactless monitoring for steel structures subjected to impact pile driving, representing a promising step toward more efficient and cost-effective monopile installations.

The integration of seawater desalination and wind energy technologies has allowed for the development of a directly wind-driven desalination system, with the potential to address freshwater scarcity issues without contributing to CO2 emissions. The system described in this manuscript consists of a wind turbine rotor, which employs a hydraulic transmission to directly pressurise seawater into a reverse osmosis desalination plant and a Pelton turbine generator. After building and commissioning of a 44 m hydraulic wind turbine prototype in the port of Rotterdam in the Netherlands, an experimental campaign was conducted to evaluate the operational range and performance of the hydraulic system. A combination of hardware-in-the-loop tests where used to get insight into the behaviour of the integrated system. The control philosophies used for automatic operation and safety of the system are compared and discussed, as well as the system's behaviour in response to different wind conditions using dummy elements to replace the desalination module. Technical challenges and achievements of commissioning and testing the system are also described, along with lessons learned.

The integration of wind energy to desalinate seawater can address the freshwater scarcity issue and alleviate the environmental impact of desalination. This paper presents the use of the Delft Offshore Turbine, an unconventional wind turbine with hydraulic transmission which can be used to directly drive a seawater reverse osmosis desalination process and to produce electricity with a Pelton turbine. A steady-state model is used to identify the potential regions at which it is possible to operate the system and to propose a system settings for maximising water production. The results show that the proposed system provides up to 300 kW of electricity and can desalinate up to 25 m³/h, at rated operating conditions.