Power potential of Rystraumen, Norway

Abstract

The maximum power potential of the tidal current Rystraumen close to Troms , Norway, is assessed both theoretically and from a depth-integrated numerical model (FVCOM). For the theoretical estimate of the maximum power potential, the topography is simplified to the situation in which the channel connects a large basin, unaffected by the energy extraction, to a closed bay. A set of governing equations is simplified to one single equation, which balances the acceleration of the current velocity, the pressure gradient and the force associated with turbine friction. The theoretical estimate is calculated to 66 MW. From the numerical simulations the maximum power potential is estimated to be 40 MW, if one allows for a uniform energy dissipation over one entire cross section of the channel. The reason for the difference in the theoretical and the modeled estimates is that in reality the flow of water is not entering a closed bay, but a pool which is connected to the rest of the sea through three channels. The same difference between theoretical and modeled results is reported in other studies where similar sitiuations have been considered.