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  • Open Access

Self-contained power optimization for wave energy conversion: A step change in generation

Zhijing Liao*,†, Samuel Draycott‡, Peter Stansby§, Jinqian Du∥, and Guang Li

  • *Present address: Kunming University of Science and Technology, Kunming, China.
  • †Contact author: zhijing.liao@kmust.edu.cn
  • ‡Contact author: samuel.draycott@manchester.ac.uk
  • §Contact author: p.k.stansby@manchester.ac.uk
  • ∥Contact author: jinqian.du@postgrad.manchester.ac.uk
  • Contact author: guang.li@manchester.ac.uk
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Phys. Rev. Research 8, 013075 – Published 23 January, 2026

DOI: https://doi.org/10.1103/f24b-9hkc

Abstract

Wave energy holds immense potential, yet to date progress has been hampered by substantial design challenges and perceived high levelized cost of electricity (LCoE). Control strategies could be vital for improving the economic viability of wave energy converters (WECs), yet practical implementations demonstrating performance remain limited. Here, we present, and implement experimentally for the first time, a self-sufficient control system requiring no external measurements. It is physically demonstrated for the complex hinged, Moored, MultiMode, Multifloat WEC, called M4. The controller operates within a linear noncausal framework to optimize generator torque, where excitation forces are estimated and predicted autoregressively. A real-time state-space hydrodynamic model, based on the Cummins-type linear diffraction-radiation formulation, enables operation based solely on motor-generator torque-speed data. In a first-of-its-kind wave basin experiment, the control strategy is shown to over double energy capture (up to a 125% increase) whilst also demonstrating performance in both unidirectional and directionally spread irregular wave conditions, mimicking real ocean complexity. Site-specific assessment across four European wave sites demonstrates substantial implications for system design and performance: The optimal device size is approximately 40% less than that defined by the average peak period of a site, as often used, and with control implemented, the average power per unit mass (approximately proportional to the inverse of LCoE) increased by about 100% across the four sites. This represents a step change toward the commercial viability of wave energy.

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Outline

Information

Phys. Rev. Research 8, 013075– Published 23 January, 2026
  • Received 30 March 2025
  • Accepted 19 October 2025
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