No abstract

Summary Marine renewable energies are promising enablers of a cleaner energy future. Some technologies, like wind, are maturing and have already achieved commercial success. Similar to their terrestrial counterparts, marine renewable energy systems require energy storage capabilities to achieve the flexibility of the 21st century grid demand. The unique difficulties imposed by a harsh marine environment challenge the unencumbered rise of marine renewable energy generation and storage systems. In this study, the fundamentals of marine renewable energy generation technologies are briefed. A comprehensive review and comparison of state‐of‐the‐art novel marine renewable energy storage technologies, including pumped hydro storage (PHS), compressed air energy storage (CAES), battery energy storage (BES), hydrogen energy storage (HES), gravity energy storage (GES), and buoyancy energy storage (ByES), are conducted. The pros and cons, and potential applications, of various marine renewable energy storage technologies are also compiled. Finally, several future trends of marine renewable energy storage technologies are connoted.

No abstract

No abstract

Aerodynamic wake interaction between commercial scale wind turbines can be a significant source of power losses and increased fatigue loads across a wind farm. Significant research has been dedicated to the study of wind turbine wakes and wake model development. This paper profiles influential wake regions for an onshore wind farm using 6 months of recorded SCADA (supervisory control and data acquisition) data. An average wind velocity deficit of over 30% was observed corresponding to power coefficient losses of 0.2 in the wake region. Wind speed fluctuations are also quantified for an array of turbines, inferring an increase in turbulence within the wake region. A study of yaw data within the array showed turbine nacelle misalignment under a range of downstream wake angles, indicating a characteristic of wind turbine behaviour not generally considered in wake studies. The turbines yaw independently in order to capture the increased wind speeds present due to the lateral influx of turbulent wind, contrary to many experimental and simulation methods found in the literature. Improvements are suggested for wind farm control strategies that may improve farm‐wide power output. Additionally, possible causes for wind farm wake model overestimation of wake losses are proposed.Copyright © 2012 John Wiley & Sons, Ltd.