The rotor blades of wind turbines represent up to 30% of the total turbine cost. The blades are also heavy and difficult to transport. By introducing a new frame-work based design for rotor blade, the cost and weight can be reduced dramatically. Being module, the transportation can also be done at a lower cost. In the project Ongeas worked on analyzing and optimizing the design with regards to aerodynamic efficiency, low manufacturing cost, low mass and with a high degree of modularity.