Tidal range could power one third of the world, study says

In theory, one third of global electricity needs could be provided by the world’s tidal range, according to a new comprehensive state-of-the-art review of tidal range power plants.

The review, published by researchers from the School of Ocean Sciences at Bangor University, estimates that 5792 TWh could be produced by tidal range power plants – using tidal lagoons and barrages to convert energy from the highly predictable rise and fall of the world’s oceans.

However, 90% of the resource is distributed across just 5 countries, with both the UK and France having a significant share of that resource, according to the paper.

Published in Renewable Energy – an international peer-reviewed journal – the review also discusses how tidal lagoon power plants can be optimized, through detailed modelling, and via optimizing the mode of operation of multiple tidal lagoons located along a coastline, using a blend of flood only, ebb only, and two-way generation plants.

“Tidal lagoons are attracting national and international attention, with the 2017 publication of the government commissioned ‘Hendry Review’, which assessed the economic case for tidal lagoon power plants, and suggested that a ‘pathfinder’ project in Swansea Bay could be the start of a global industry.

“Geographically, the UK is in an ideal position, containing many regions of large tidal range as a result of the resonant characteristics of this part of the European shelf seas,” explains lead author, Simon Neill.

However, Sophie Ward, another author of the study, cautioned that although tidal lagoons are likely to be less intrusive than tidal barrages that tend to span entire estuaries, “they require careful design and planning to minimize the impact on the local environment.

“With significant global potential for tidal range power plants, we need to closely monitor environmental consequences of extracting energy from the tides, and be cautious of altering natural habitats by building structures and impounding water in lagoons or behind barrages.”