# Wind Turbine Technology Trends
## 3 Discussion
### Offshore Wind Turbine Development
Figure 8: Installed and planned new annual capacities of offshore turbines until 2025 [53]. Figure 7: Announced offshore wind foundation types in future projects [53]. Wind turbine floating structures must withstand harsh conditions. The combined effects of high winds and waves cause vibration, material fatigue, and severe loads on the elements of the wind turbine. These problems lead to increased maintenance efforts and increase the risk of failures [59]. Therefore, maintenance is very important as it reduces the number of repairs required. Improved maintenance scheduling can reduce costs and increase turbine availability. The possibility of remote maintenance has also developed. This includes remote monitoring, which allows early detection of problems and preventive maintenance. Subsea equipment has also been developed for inspection and repair of components that are difficult to access [53]. Improving and upgrading the power grid is necessary in many countries to accommodate large amounts of renewable energy, including energy from offshore wind farms. Policymakers urgently need to mobilise more public and private investment in secure, smart, and flexible grids that can accommodate an ever-increasing share of renewable energy. Otherwise, the availability of appropriate grid connections, capacity, and transmission lines may be a significant bottleneck to the growth of new utility-scale wind and solar energy projects. Grids need to be comprehensively modernised not only in terms of physical infrastructure, but also in terms of intelligence. The grid in the future energy system is likely to be a data network grafted onto a physical grid, enabling multidirectional energy and information flow with effective and precise controls. In addition, the development of ports and vessels is accelerating to keep pace with the increasing production of offshore wind turbines and the increase in their dimensions [60]. A sharp increase in offshore wind farm projects leads to a rise in demand for submarine cables. The market is divided into cables connecting an offshore substation to the onshore station and cables connecting adjacent wind turbines and offshore substations. It is estimated that the need for offshore cables in Europe will be about 2000 km per year. In addition, there are efforts to install cables with a voltage of 66 kV, compared to the current 33 kV [53]. The work of [PERSON] et al. [61] examines the market trends for offshore technologies in Europe and provides a detailed overview of installed and planned capacity. There is a clear shift from smaller reduction gear turbines to larger direct drive turbines. To investigate the impact of this shift on wind farm reliability, the failure rates of 39 wind farms in Europe and South America with direct drive and geared turbines were analyzed. The analysis revealed several key similarities between the configurations, with the electrical system responsible for the majority of turbine failures in both cases. When considering the total downtime due to failure of all components, the direct drive wind turbine had the highest value, primarily due to the relatively higher downtime associated with the electrical system,  
Figure 9: Cumulative floating offshore wind capacity [53]. generator, and control system. This indicates that further improvements are needed for direct-drive power plants. It is estimated that the cost of electricity for floating offshore wind turbines will decrease from $160/MWh (2010) to $50-105/MWh (2030), i.e., it can be said that technological progress in the design of floating wind turbines will lead to a significant reduction in costs [2, 62]. In this way, the predictions for the year 2050 (Figure 1) could come true that most of the electricity generation will come from wind turbines. Hydrogen will play a key role in Europe's carbon-neutral economy, as many current scenarios show. Hydrogen produced by electrolysis of electricity from wind turbines is an emerging technology.