Concentrating Wave Power: A Function of Reduced Wavelengths Michael Raftery M.E. Martin & Ottaway, Inc.

2.21 Second, 5.1cm (2 Inch)-High Waves – 15cm (6 Inch) Platform Depth Wave Wire 2 (WW2) is Visible in this Photo over the Platform Photo courtesy of: Michael Raftery and Stevens Institute of Technology – Davidson Laboratory

Submerged Platform Concentrates Wave Power Wave Wire 1 (WW1): H =0.051m (2.0in) ,Cg = 1.97 m/s at 1.98m tank depth, E = 3.27 J/m^2, P = 6.43 W/m Wave Wire 2: H = 0.127m (5.0in), Cg = 1.14 m/s at 0.15m (6in) platform depth, E = 20.25 J/m^2, P = 23.07 W/m 259% increase in power density

Same Power in Less Space

Conservative Process Mass, Energy, and Power are Conserved in this Process: Due to the instantaneous change in water depth from the bottom of the wave tank to the top of the submerged platform in the wave tank or from the seafloor to the top of the platform in the open ocean, mass flow, energy and power are conserved unlike naturally occurring surf waves which lose power before reaching shore due to interacting with the seafloor for many miles as they approach shorelines as found on the East Coast of the United States

Optimal Wave Focusing Wave power can be concentrated up to four times the incoming wave power over a wide range of conditions. The platform depth and slope can be varied by winches attached to anchors in the seafloor to optimize the platform position depending on the real-time wave climate. Platform positions can be optimized for converting wave power to electricity or breaking waves to reduce the impact of waves on the shore behind the units

Long term goal – Industrial Scale Wave Farms BOEM OCS Block 6256 https://www.boem.gov/Renewable-Energy-Lease-Map-Book/ Google Earth Pro

Capacity and Availability Factors Capacity Factor(ratio): The total power output of a unit or system divided by the maximum potential total power output of a unit or system. An annual average power output of 1.1MW per SurfWEHD unit was calculated from NOAA/NDBC Buoy 44025 hourly wave height data, based on a 60m x 30m SurfWEHD top deck plate and 50m x 20m x 2m surface float. Availability Factor(ratio): The total time that a system is able to produce electricity over a certain period divided by the amount of the time in the period. Equivalent Availability Factor (EAF) For renewable systems, only partial capacity is available for the majority of the plant lifecycle. If the partial capacity is deducted from the time a plant is able to produce electricity, the resultant is the EAF. The SMWEHD has a fairly low Capacity Factor: 1.1MW/5.2MW = 21% which would go even lower if more powerful generators are installed, but that has very little effect on the cost or economics of the overall system as larger generators are only slightly more expensive. The SMWEHD has a fairly high Availability Factor off New Jersey 1MW+ for 7200 of 8760 hours per year (82% Availability Factor) which has a significant impact on the economics of a SurfWEHD wave farm

Dispatchability SurfWEHD onboard energy storage enables units to dispatch power on demand regardless of real-time wave conditions. 1MW for 30 minutes 500kW for 1 hour Onshore hydrogen production facilities will be integrated into industrial scale wave farms to provide industrial scale energy storage and electric power generation capabilities during periods of flat seas. For example, 400MW of electric power is projected to go into hydrogen production during periods when waves are over 3 meters high for a 200 unit SurfWEHD wave farm off Barnegat Inlet, New Jersey.