On the optimal sizing of power take-off systems for wave energy converters

Journal Article · Tue May 20 00:00:00 EDT 2025 · Renewable Energy

DOI:https://doi.org/10.1016/j.renene.2025.123375· OSTI ID:2573882

McGilton, Ben ^[1]; Nakhai, Aryana Y. ^[1]; McNally, Jim ^[1]

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1. National Renewable Energy Laboratory (NREL), Golden, CO (United States)

The power take-off (PTO) system in a wave energy converter (WEC) is the means by which the energy in an ocean wave is converted into useful energy. There has been a general lack of technology convergence in the wave energy industry and PTO design has been largely device-specific with the design process determined by the WEC developer. An optimized PTO design can significantly affect the efficiency, reliability, performance, and overall cost and viability of a device. There remains a need in the marine energy industry for best practices and efficient design processes to be identified as it could greatly benefit developers and researchers in designing an optimal WEC PTO. This research utilizes the open-source Matlab-Simulink based software, WEC-Sim, which was developed by the National Renewable Energy Laboratory, and the Eagle, a high-performance computing system, to model and optimize two WECs of different archetypes and then investigates if any trends exist that can be exploited for greater efficiency in optimal PTO design. The results from this research indicate that there may be an optimal sizing for WEC PTOs for both power and PTO force rating and that substantial reductions can be made in the cost of a device without significant loss in the energy produced. Furthermore this optimal sizing may be independent of WEC type and deployment location. With an optimal, or near optimal, approach to WEC PTO sizing demonstrated, a methodology is proposed to address the challenge of nameplate ratings in the wave energy industry.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Water Power Technologies Office
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 2573882
• Report Number(s): NREL/JA--5700-87775
• Journal Information: Renewable Energy, Journal Name: Renewable Energy Vol. 252; ISSN 0960-1481
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

13 HYDRO ENERGY
16 TIDAL AND WAVE POWER
LCOE
LCOx
PTO
WEC
capacity factor
nameplate rating
wave energy