On the economic feasibility of tidal range power plants

Abstract

The wave potential energy associated with tides presents a promising sustainable energy resource. Uncertainties on the economic case of tidal range power plants are a known bottleneck hindering the development of the industry. Significant costs depend on each design's general arrangement, which includes both mechanical components and the associated civil works. Research on tidal range structures suggests yield may be maximised through operation strategy optimisation. While highlighting the untapped potential, such optimisation alone is insufficient to support the feasibility of prospective projects. We combine operation optimisation and hydrodynamic impact analyses within a cost evaluation framework for tidal range structures focusing on capital costs and levelised cost of energy. We apply this consistently and widely across idealised and historic proposals and then proceed to perform a re-design of tidal range power plants to deliver a consistent comparative basis. The operation of tidal range plants is represented in regional coastal ocean models, acknowledging tide variability based on shallow water equation modelling. A modelling case study encompassing the UK's West coast extending to the continental shelf serves to benchmark tidal range schemes of different designs and scales. The cost evaluation framework is compared against reported cost projections and is the first to consider the geospatial variations of multiple options consistently.