Airborne wind energy is a new research field that aims to harvest winds at high altitudes. The pumping kite concept investigated at the Delft University of Technology is based on leading edge inflatable kites that divide a generation cycle into three phases: traction, retraction, and transition. This research project aims to optimise the trajectory flown by the kite to increase the cost-competitiveness of the system. Thus, the complete system was simulated, and a sensitivity analysis was conducted. The results show that there is an area in the wind window that maximises the power production of the cycle. This area is defined by the wind speed, the shape of the figure, and the reel in/out force. Based on the findings, an algorithm that seeks the optimal path during the flight was developed. In the case study, the algorithm led to a 100% increase in cycle power and a 16% increase in the average traction power.

Energy demand from wind greatly increases, as such more remote sites need to be explored in order to find good wind resources. These remote sites are driving the industry further offshore and therefore into extreme wind and sea conditions. This push towards extreme conditions requires technological advancements concerning the wind turbine loads, power production and installation. The levelised cost of wind energy is strongly dependent on the capital expenditures and thus on the installation and logistics of erecting a wind turbine offshore. Improving the robustness of the installation to higher wind velocity and turbulence will increase the weather window and therefore drastically decrease the levelised cost of energy (LCoE). This thesis will focus on one particular technique of wind turbine installation: Horizontal Single Blade Mounting (HSBM).
HSBM is a wind turbine blade lifting technique performed by Siemens Wind Power (SWP). This technique is currently limited to low wind speeds, which contradicts the fact that the industry is targeting high wind speed offshore sites. This technical problem is the basis of the thesis study. This thesis study will answer three research questions in order to improve future lifting
methods. In a nutshell these questions are: one, how to model the aerodynamic forces and dynamic behaviour of a hoisted wind turbine blade?, two, what are the critical parameters affecting the blade response? and three, how can single blade mounting be improved for higher wind speeds?.