As marine current turbines become more widely used, and their role within the
renewable energies gets a higher priority in the future UK Government’s energy
plans, it is necessary to achieve a better understanding of this technology for it to be
smoothly introduced into the energy sector.
The only way marine current turbines can be connected into the grid and make some
significant contribution to requirements is being part of a farm. Because of this, and in
the same way that was done with wind turbines when they were starting to show their
now undeniable potential, it is necessary to study, simulate and understand the
interactions between marine current turbines when they are deployed in the form of an
array. This project tried to clarify to a modest extent how a turbine interacts with the
other devices surrounding it.
Real physical small scale models of a horizontal axis marine current turbine were
designed to behave as closely as possible to a real machine, and an electrical system
was designed for the whole assembly to simulate the way a real marine current turbine
would be producing energy in a full scale array on a real site. The array was tested
inside a flume for different configurations, with a range of different loading ratios for
the turbines, trying to simulate how a real grid-connected array might have demand
fluctuations and hence different power outputs.
The performance of the turbines was analyzed focusing on their power output, and
wake and blockage effect analysis were carried out based on the flow speed
measurements taken.
Findings showed the importance of the different configurations when trying to
optimize an array, examined the interactions between array configuration and the
loading ratios of the turbines, and revealed the clear impact of the array effects on the
overall power output.
Marine Current Turbines: Array Effects