Apparatus for harnessing wave energy.

FIELD OF INVENTION A preferred form of this invention relates to means for use in converting the energy in ocean waves to electrical energy.

BACKGROUND

It is known to harness tidal or wave energy for the purpose of generating electricity. An object of at least a preferred form of the present invention is to provide a useful alternative for use in harnessing the kinetic energy of moving water.

SUMMARY OF INVENTION

According to one aspect of the invention there is provided apparatus for use in converting kinetic energy from moving water to electrical energy, the apparatus comprising a ramped water channel, a water receiving unit, a turbine, and transportation means; the apparatus formed such that when it is in use it can be transported via the transportation means so that the ramped water channel enters a body of water to an adjustable degree such that water contacts and moves up the ramped channel and into the water receiving Unit where it drops under gravity and in so doing causes the turbine to turn to facilitate the generation of electricity.

Preferably the channel is set at an angle such that it has a low end adapted to contact the body of water and a high end open to the water receiving unit.

Preferably the channel is cat an angle which causes waves to form and move up the channel.

Preferably the turbine is within the water receiving unit.

Preferably the turbine is associated with a drain outlet in a floor of the water receiving unit.

Preferably the water channel and the water receiving unit can be angle adjusted.

Preferably the transportation means comprises a track or tracks at the edge of the body of water, and the channel and the water receiving unit can move via the track or tracks so that the channel enters the water and can be withdrawn from the water when desired.

GENERAL DESCRIPTION OF THE DRAWINGS

Some preferred embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, of which:

Figure 1 is an isometric view of a wave energy converter;

Figure 2 is a side elevation view of the converter;

Figure 3 is an overhead view of a wave box forming part of the converter; and

Figure 4 is a bottom view of the wave box; Figure 5 - is a cutaway view of the wave box.

DETAILED DESCRIPTION

Referring to figures 1 and 2, the wave energy converter comprises a channel in the form of a ramped wave board 1 and a wave box 2. The converter incorporates a set of wheels 3 and tracks 4 which enable the wave board 1 and wave box 2 to be moved closer to or further from the edge of a body of water such as the sea.

The wheels 3 on which the wave board 1 and wave box 2 move may be arranged in the manner of railway bogies, and the tracks 4 may be formed in the manner of a railway line. As shown, the arrangement is that of twin slipways, the forward parts of which are submerged in the sea. The ends of the slipways preferably have buffers to stop the wave box going into the water to below a safe operating depth. Preferably the slipways angle into the sea at about 10 degrees from the top of a breakwater or similar shore line structure. Movement along the slipways may be facilitated by winches and winch cables running to a winch pit set in the breakwater or shore.

As shown in figure 1 the wave board is funnel shaped with a wider forward end 5 which can be moved into the sea, and a narrower upper end 6 which may remain out of the water. The ramped wave board 1, when its forward end 5 is submerged to a reasonable degree, funnels waves resulting from ocean swells up into the wave box 2. The water enters at a high point 7 of the wave box and then drops under gravity

through an aperture in a rear part of the wave box's floor to contact and turri a turbine. The rotary movement of the turbine is used to generate electricity.

Because the slipways enable the wave board 1 to be adjusted in terms of how far it proceeds into and under the sea the wave energy converter can be positioned for optimal performance, depending on sea level, tidal movements, and the amount of sea swell. Indeed in at least some instances incoming ocean swells contacting the ramped wave board 1 create waves which move up to the wave box 2. The water in the wave box 2 responds to the force of gravity, and more particularly flows through a turbine opening in the floor of the wave box, turning the turbine as the water drains back towards the ocean.

In preferred embodiments of the invention the wave box 2 is a steel open mouthed oblong container which tapers towards its rear and terminates in a blunt end 8. In one embodiment the wave box 2 may be approximately 10 m long, 5 m wide and 4 m high at its high end and 2 m wide at its low end. The roof 9 of the wave box is thus sloped as is evident in figure 1.

Referring to figure 5, in some embodiments of the invention the turbine 12 is within the wave box 2 and set to rotate about a vertical shaft 13 running between the wave box's roof and floor. For desired performance the upper edge of the turbine may be about level with the floor of the wave box. The distance from the turbine's central casing to the edge of its blades may be approximately 0.5 m and the blades may be enclosed by a metal surround 15. The surround extends to provide a short pipe protruding at the bottom of the wave box 2 by about 0.5 m. A fly wheel 11 may be fitted to the upper end of the turbine's shaft, above the roof of the wave box; to dampen power surges. A generator 14 is preferably located within the turbine's core below the floor of the wave box or alternatively around the generator's shaft above the wave box's roof.

Referring to figures 3 and 4, the wave board 1 may be welded from steel and may run from in front of the wave box 2 down into the ocean for a distance of approximately 20 m. At its lower forward end 5 the wave board 1 may be about 12 m wide and at its upper end 6 it may be about 5 m wide. The steel side walls 10 of the wave board 1 are shown in figures 1 and 2.

In some embodiments of the invention a lift mechanism may be fitted at the underside of the wave board 1 and wave box 2 and used to raise the front of the wave box 2 and the attached narrow end of the wave board 1 so that the bottom end of the wave box is aligned with and about 1 m above sea level. The wave board 1 and wave box 2. may be joined to .one another by way of a hinge. The wave energy converter has means to set the height and attitude of the forward end 7 of the wave box relative to sea level. A height adjustment mechanism is preferably associated with the mid section of the wave board.

In the course of constructing the wave energy converter, or for servicing it, a pair of service railway style rails may be laid across the top of a breakwater joined to the slipway rails 4.

While some preferred forms of the invention have been described by way of example it should be appreciated that modifications and improvements can occur .without departing from the scope of the appended claims. .