WaveSurfer™ system is a wave energy converter that generates electricity by harnessing renewable energy of ocean waves in a manner that is both economically viable and environmentally friendly.
WaveSurfer™ is a reliable, inexpensive and efficient off-shore system, that can be installed on different depths by mooring. The system contains no expensive or complex parts, lubricants, high precision hydraulics or air pumps, everything that makes other systems more expensive, vulnerable to destructive forces of nature and potentially hazardous.
Principle of Operation: WaveSurfer technology utilizes finite depth of ocean waves and drag force of water.
Motion of water beneath the surface decreases exponentially with depth. No matter how significant wave action is on water surface, water at a depth of one-half wavelength L/2 (wave base) and below is motionless.
WaveSurfer unit comprises two bodies, (1) moored to seabed buoyant body and (2) suspended from it fully submerged frame with installed rotors and electric generator. The submerged body is held at a depth of around one-half wavelength where the water is motionless.
The buoyant body rises with each wave dragging the attached submerged body upward through the region of motionless water until a wave reaches its crest. As the wave falls, the gravity drags the said submerged body downward through the same region of motionless water until the wave reaches its trough.
This up and down motion through a region of stationary water causes rotation of the rotors due to water resistance force (drag force). Rotor buckets are so shaped to move through water with minimum resistance in one direction (drag coefficient CD – 0.09) and with maximum resistance in the opposite direction (drag coefficient CD– 2.0).
Rotation is transmitted to an electric generator installed on the submerged body. The generator is equipped with a flywheel and overrunning clutch to maintain constant rotation.
The technology utilizes the water resistance (drag) that opposes the relative motion of the submerged platform with installed rotors through the water. Drag forces act in a direction opposite to the oncoming flow velocity.
FDrag = ½ρU2ACD
- FDrag - the force of drag, which is by definition the force component in the direction of the flow velocity
- ρ - the mass density of the fluid
- U - the velocity of the object
- A - the area being used
- CD - the drag coefficient
One of the main advantages of the WaveSurfer™ system is its remarkably high survivability level. The system's energy conversion and power generation parts are completely submerged at such depth where the water is not affected by the surface waves, therefore is motionless. There is no rigid connection between two bodies of the unit. The floating buoy and the submerged frame with rotors and generators are flexibly connected to each other by lines, cables or chains.
WaveSurfer™ is designed to operate in harmony with waves rather than attempting to resist them.
WaveSurfer™ system has high capacity factor and operates across a variety of wave heights and periods making it base load energy option.
Due to the system's modular design and high scalability, it can occupy a multitude of markets e.g. remote islands, marinas, oceanside resorts, shore communities, ports, fish processing plants, naval installations, as well as multi-megawatt grid-connected wave power farms.
WaveSurfer™ can also be used as an autonomous power generator for remote ocean-based platforms e.g. military, oil rigs, meteorological, oceanographic.
Because of the modular, easy-to-assemble design each unit can be cost effectively transported and installed anywhere in the world. Parts are shipped in regular 20' or 40' containers and assembled at the installation site.
WaveSurfer™ power farm's capacity can be increased incrementally to match the gradual load growth.
WaveSurfer™ substantially outperforms the competing technologies with respect to efficiency, survivability, cost and maintenance.
- Power output: from 1 kW to 10 MW per 1 unit;
- Minimum life span before significant repairs: 25-35 years;
- Type: “point absorber” installed on a variety of depths by mooring;
- Minimum operational wave height: 0.5 m;
- Materials: plastic, rubber, steel; Energy delivery method: underwater cable;
- Scalability: from a single unit to multi-unit, multi-megawatt farms.