Sensitivity of tidal lagoon and barrage hydrodynamic impacts and energy outputs to operational characteristics

Athanasios Angeloudis,Roger A Falconer

doi:10.1016/j.renene.2016.08.033

Abstract

The feasibility and sustainable operation of tidal lagoons and barrages has been under scrutiny over uncertainties with regards to their environmental impacts, potential interactions and energy output. A numerical modelling methodology that evaluates their effects on the hydro-environment has been refined to consider technical constraints and specifications associated with variable turbine designs and operational sequences. The method has been employed to assess a number of proposals and their combinations within the Bristol Channel and Severn Estuary in the UK. Operational challenges associated with tidal range power plants are highlighted, while also presenting the capabilities of modelling tools tailored to their assessment. Results indicate that as the project scale increases so does its relative hydrodynamic impact, which may compromise annual energy output expectations if not accounted for. However, the manner in which such projects are operated can also have a significant impact on changing the local hydro-environment, including the ecology and morphology. Therefore, it is imperative that tidal range power plants are designed in such a way that efficiently taps into renewable energy sources, with minimal interference to the regional hydro-environment through their operation.

Highlights

Tidal range power plants are designed on the principle of creating an artificial tidal phase difference by impounding water, and allowing it to flow through turbines to generate energy, in the form of electricity
Details have been provided on the refinement and application of a two-dimensional hydrodynamic model for the assessment of tidal range structure operations
Following preliminary optimisation and validation studies, the model was employed to assess a number of tidal barrage and lagoon proposals within the Severn Estuary and Bristol Channel, in the UK

Summary

Introduction

Tidal range power plants are designed on the principle of creating an artificial tidal phase difference by impounding water, and allowing it to flow through turbines to generate energy, in the form of electricity. The first large scale tidal range structure has been the La Rance barrage in France, in operation since 1966 [27] This was followed by the 20 MW single turbine Annapolis Royal generating station in Canada (1984) and the more recent 254 MW Lake Sihwa tidal power station in South Korea [8]. Contrary to their successful performance for sustainable and predictable energy production, there are mounting concerns over the environmental impacts induced by the presence of such renewable energy structures in estuarine and coastal waters.

Objectives

Methods

Results

Conclusion