These 2 (two) PhD vacancies are part of the H2020 X-Rotor project, which aims to develop disruptive new offshore wind turbine concept known as the “X-Rotor”. The X-Rotor has potential to reduce the cost of energy (CapEx and OpEx) from offshore wind by up to 20%, based on a conservative estimate from early feasibility study work. The X-Rotor concept is an offshore Vertical Axis Wind Turbine with blade-tip mounted Horizontal Axis Wind Turbines for power conversion.