Over the last couple of decades, there has been increased interest in environmentally friendly technologies. One of the renewable energy sources that has experienced huge growth over the years is wind power with the introduction of new wind farms all over the world, and advances in wind power technology that have made this source more efficient. This recognition, together with an increased drive towards ensuring the sustainability of wind energy systems, has led many to forecast the drivers for future performance. This study aims to identify the most sustainable wind turbine design option for future grid electricity within the context of sustainable development. As such, a methodology for sustainability assessment of different wind turbine design options has been developed taking into account environmental, data uncertainty propagation and economic aspects. The environmental impacts have been estimated using life cycle assessment, data uncertainty has been quantified using a hybrid DQI-statistical method, and the economic assessment considered payback times. The methodology has been applied to a 1.5 MW wind turbine for an assessment of the current situation and potential technology improvement opportunities. The results of this research show that overall, the design option with the single-stage/permanent magnet generator is the most sustainable. More specifically, the baseline turbine performs best in terms of embodied carbon and embodied energy savings. On the other hand, the design option with the single-stage/permanent magnet generator performs best in terms of wind farm life cycle environmental impacts and payback time compared to the baseline turbine. With respect to the design options with increased tower height, it is estimated that both designs are the least preferred options given their payback times. Therefore, the choice of the most sustainable design option depends crucially on the importance placed on different sustainability indicators which should be acknowledged in decision making and policy.