With the focus of the tidal energy industry shifting from demonstration to large scale deployment and cost reduction, there is an important question which is hard to avoid: Can 1MW tidal systems really compete with multi megawatt offshore wind turbines?
The answer to this question is not obvious. Total offshore wind costs decline as turbines get bigger. This is because infrastructure and maintenance costs fall, but these gains are partly offset by turbine costs increasing. The same counteracting influences are likely to hold for tidal systems but if the balance of costs in tidal power lies nearer the parts which get more expensive as they get bigger, scaling up may yield no benefits at all.
The costs and benefits of scaling tidal systems can therefore only be assessed by understanding the balance of costs within a system, and how each cost centre is affected as turbines increase in size. This paper discusses the conclusions reached by the use of Pulse Tidal’s techno-economic model to estimate how the costs of a “generic” tidal turbine change with scale. These results are then used as a basis for answering the question of whether bigger will be better for tidal systems, and if so, whether some routes to higher unit capacity are better than others.
