Tidal Turbine Performance and Energy Extraction Strategies

Tidal turbines harness the kinetic energy of moving water driven by lunar and solar gravitational forces. Their reliability and predictability make them a cornerstone of marine renewable energy, yet device performance remains sensitive to complex flow conditions and environmental interactions. Performance is typically assessed by power and thrust coefficients, which quantify the fraction of available kinetic energy converted and the hydrodynamic loading on the rotor, respectively. Key factors influencing these metrics include inflow shear, turbulence intensity, bed and surface proximity, and wake recovery. In practice, individual turbine design must be paired with strategic array placement to optimise collective extraction while mitigating wake interference. Computational models range from blade element momentum theory to fully coupled shallow-water simulations, supported by field measurements for validation. Energy extraction strategies extend beyond singular devices to integrated schemes that balance extraction with ecological impact, grid integration and socioeconomic considerations. Innovations in floating platforms, adaptive control and real-time monitoring promise to enhance resilience in variable tidal regimes. As global demand for low-carbon power grows, understanding turbine–flow and turbine–turbine interactions is imperative to scale tidal energy from demonstration to commercial arrays with minimal environmental footprint.

Research from Nature Portfolio

Recent studies have provided unprecedented measurements of flow dynamics around a utility-scale floating tidal turbine. Using aerial drones and in-water acoustic profiling, researchers characterised sheared inflow conditions with turbulence intensities exceeding 20% and length scales greater than 0.4 rotor diameters. Detailed wake mapping revealed velocity deficits of up to 20% at four rotor diameters downstream and far-wake propagation beyond thirty diameters. These high-resolution, multiscale observations bridge the gap between numerical models and real-world environments, informing validation of advanced flow physics simulations and guiding design of resilient floating turbine platforms.

Tidal Turbine Performance and Energy Extraction Strategies publication trend

The graph below shows the total number of articles in tidal turbine performance and energy extraction strategies across all publications each year (not limited to Nature Index journals).

Technical terms

Tidal stream energy: Kinetic energy extracted from horizontal tidal currents.

Wake: Low-velocity, turbulent region downstream of a turbine where flow recovers gradually.

Turbulence intensity: Ratio of root-mean-square velocity fluctuations to mean flow speed, indicating flow unsteadiness.

Axial induction factor: Fractional reduction in flow speed at the turbine rotor relative to upstream undisturbed flow.

Adjoint optimisation: Numerical method using adjoint equations to calculate design sensitivities efficiently for large optimisation problems.

Levelised cost of energy (LCOE): Average lifetime cost per unit of electricity generated, accounting for capital, operational and maintenance expenses.

References

1. Sheared turbulent flows and wake dynamics of an idled floating tidal turbine. Nature Communications (2024).
2. Impacts of tidal stream power on energy system security: An Isle of Wight case study. Applied Energy (2023).
3. Hydrokinetic energy conversion: Technology, research, and outlook. Renewable and Sustainable Energy Reviews (2016).
4. Tidal turbine array optimisation using the adjoint approach. Renewable Energy (2014).
5. Experimental study of the mean wake of a tidal stream rotor in a shallow turbulent flow. Journal of Fluids and Structures (2015).