Abstract
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.