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

2. 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

3. 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 = J/m^2, P = W/m
259% increase in power density

4. Same Power in Less Space

6. 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

7. 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

8. Long term goal – Industrial Scale Wave Farms
BOEM OCS Block 6256
Google Earth Pro

9. 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 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

10. 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.