Healy Wave Energy, LLC is developing a wave energy conversion (WEC) device that is designed for reliability, safety, and economical power production for island and coastal communities. The unit employs a novel low operating pressure pneumatic Power Take-Off (PTO) and a novel low-impact-force hydrodynamic end-stop feature. The 43-ton prototype device, constructed in Clearwater, Florida, will be deployed at the University of New Hampshire Open Ocean Test Site starting in 2018 for a long-term test of its power production and longevity.
MMC developed a custom model that coupled the multibody hydrodynamics of the device with the pneumatics of the PTO, and included hydraulic brake dynamics and the physics of a variable ballast system. This allowed MMC to:
- Quantify system losses.
- Evaluate annual energy production and the system’s ACE metric (the ratio of average climate capture width to characteristic capital expenditure).
- Incorporate control algorithms through a simulated Programmable Logic Control (PLC).
- Advise on critical design decisions.
Extreme Event Analysis
MMC also incorporated nonlinear, large-displacement mooring dynamics to evaluate the system’s response to extreme storms. This included:
- Deriving extreme event parameters (50-year storm conditions) from historical data.
- Analyzing extreme value statistics (e.g. snap loads).
- Implementing best practices in model-driven design to optimize the mooring for cost, power production, stability, and reduced peak loads.