Laboratory Testing to Assess the Feasibility of Polyurethane Flat Belts for Marine Energy Applications

Journal Article · Thu Aug 28 00:00:00 EDT 2025 · Journal of Marine Science and Engineering

DOI:https://doi.org/10.3390/jmse13091652· OSTI ID:3011862

Panzarella, Justin ^[1]; Jenne, Scott ^[1]; Simms, Andrew ^[1]

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

Polyurethane flat belts have received limited scientific attention as load-bearing elements in marine energy systems, particularly in applications involving dynamic tensile and bending loads. This study evaluates their potential as a replacement for traditional wire ropes in marine energy applications, with a focus on their ability to be integrated into winch-driven wave energy converters where bending and tensile stresses can make long-term operation difficult. Polyurethane belts are hypothesized to offer enhanced fatigue resistance due to their reduced thickness in the bending plane and therefore lower bending stresses. This research involves a series of tests utilizing the National Renewable Energy Laboratory’s (NREL) Large-Amplitude Motion Platform to replicate the dynamic conditions experienced by mooring lines of winch-based point-absorber-type marine energy converters. The conditions tested include unequal coiling and uncoiling tensions and load cases resulting from the device’s unconstrained movement relative to its anchor, such as twisting and off-axis loading. Results from this study show that polyurethane flat belts can achieve more than 198 percent of the fatigue life of a conventional wire rope under similar load profiles. The stress concentrations resulting from off-axis loading and cumulative twist beyond the system’s allowable limits have been identified as potential failure modes for flat belt mooring lines used in winch-driven wave energy converters deployed in ocean environments. To mitigate these risks, the use of anti-spin systems and fairleads designed to accommodate off-axis loading while limiting twist accumulation is recommended.

• 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: 3011862
• Report Number(s): NREL/JA--5700-95624
• Journal Information: Journal of Marine Science and Engineering, Journal Name: Journal of Marine Science and Engineering Journal Issue: 9 Vol. 13; ISSN 2077-1312
• Publisher: MDPI
• Country of Publication: United States
• Language: English

Related Subjects

13 HYDRO ENERGY
16 TIDAL AND WAVE POWER
HERO WEC
flat belt
hydraulic and electric reverse osmosis wave energy converter
marine energy
point absorber
wave energy
winch
wire rope