Nowadays, wind energy is one of the most cost-effective and environmentally friendly energies in high demand due to shortages fossil fuels necessity reduce global carbon footprint. One main goals turbine development increase power output either by increasing blade swept area or velocity wind. In this article, a proprietary augmentation system was introduced vertical axis turbines (VAWT) free st...

While wind farms have no inherent storage to supply power in calm conditions, this paper demonstrates that large tidal turbine farms in channels have short-term energy storage. This storage lies in the inertia of the oscillating flow and can be used to exceed the previously published upper limit for power production by currents in a tidal channel, while simultaneously maintaining stronger curre...

A contra-rotating marine current turbine has a number of attractive features: near-zero reactive torque on the support structure, near-zero swirl in the wake, and high relative interrotor rotational speeds. Modified blade element modelling theory has been used to design and predict the characteristics of such a turbine, and a model turbine and test rig have been constructed. Tests in a towing t...