GB2221958A

GB2221958A - Pipe network for extracting energy from ocean waves and tidal flows

Info

Publication number: GB2221958A
Application number: GB8818498A
Authority: GB
Inventors: Edward Garside
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-08-04
Filing date: 1988-08-04
Publication date: 1990-02-21
Also published as: GB8818498D0

Abstract

A network of flexible pipes, comprising an interconnecting set of high pressure ducts 10 and an interconnecting set of low pressure ducts 11, is moored at sea. The high and low pressure ducts lead respectively into and out of an air turbine 12. Hollow boxes constructed of rigid material on the sides and top and a flexible membrane 18 at the bottom are mounted on the pipe network and each is connected into the high and low pressure ducts 10, 11 of the network. When a wave passes over a box, the air inside the box is compressed and fed through the high pressure ducts to the air turbine for the generation of usable power. When the trough of the wave occurs, the box emerges into the atmosphere and refills with air from the low pressure side of the air turbine. <IMAGE>

Description

PIPE NETWORK FOR EXTRACTING ENERGY FROM OCEAN WAVES AND FROX TIDAL FLOWS This invention relates to a network of pipes for extracting energy from ocean waves and from tidal flows.

Xost methods of extracting wave energy from the sea require a large scale construction in order to be able to confront the incoming waves and capture sufficient energy to make the project financially viable and also to survive the hostility of the environment Tidal power schemes call for extensive barrages to be erected at high capital cost and usually with adverse impact on the environment.

In the ocean wave mode, the invention floats on the sea presenting a low profile to oncoming waves and its purpose is to extract energy from the waves with a minimum of confrontation and pass it on to an amenable environment for conversion into usable power(eg electricity). In the tidal mode, the invention floats on the sea at or about low tide level. It remains at this level as the tide rises and at or about high tide extracts energy from the increased head of water above it for transmission as in the ocean mode to a convertor. There is no requirement in either mode for a permanent structure and the environment is preserved.

According to this invention there is provided a network, of any shape or size, made of hollow flexible pipes of any dimensions. The pipes serve as ducts for the conveyance of high or low pressure air and also as buoyancy floats for the network. The network is moored at sea, inshore or offshore, and in a calm sea floats at sea level. Power convertors as described below are mounted on or between pairs of pipes and protrude above the surface of the sea.A power convertor is a box constructed of rigid material on the top and sides with a flexible membrane at the bottom and has an outlet valve leading from the box into a high pressure duct within the pipe network and an inlet valve feeding into the box from a low pressure duct within the pipe network or alternatively feeding in directly from the atmosphere.

In the ocean wave mode, when a wave reaches the network,the ducts are restrained by their longitudinal and lateral attachments from rising in unison and the power convertors in the path of the wave are partly or wholly submerged. In response to the increased pressure transmitted through their submerged soft bottoms the power convertors serve as bellows pumping air through the high pressure section of the pipe network to air turbines or generators which are located outside the network, inshore, onshore or on a floating platform or ship. When the trough of the wave arrives, the power convertors emerge, are exposed again to atmospheric pressure and refill with air from the low pressure section of the pipe network returning from the turbines or from the atmosphere.In the tidal flow mode, the network is at sea level when the tide is - low and is restrained by anchorage at the same level when the tide rises. At high tide the power convertors release air into the high pressure ducts in the pipe network.The cycle repeats at the next low tide.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings(not to scale) in which: Figure 1 shows in plan, the network in situ inshore; Figure 2 shows a power convertor(front elevation)in a calm sea; Figure 3 shows a power convertor(front elevation) submerged under a wave crest; Figure 4 shows a power convertor(front elevation)when emerged in a wave trough Referring to the drawings: In Figure 1, the high pressure ducts 10 are linked together as also are the low pressure ducts 11. The high pressure ducts feed into the air turbine 12 and the low pressure ducts feed out. The network is anchored to the shore 13 and offshore 14. Intermediate anchorage is provided as necessary 15.Power convertors 16 are positioned at close intervals between a high pressure duct 10 and a low pressure duct 11; In Figure 2, the sea level 17 is above the high pressure and low pressure ducts 10 and 11 in the pipe network and under the power convertor 16. The power convertor 16 contains air at atmospheric pressure,and the flexible membrane 18 rests on the surface of the sea. The inlet valve 19 is open and the outlet valve 20 is closed.

In Figure 3, the wave crest 21 is above the power convertor 16 which now fills with water forcing the flexible membrane 18 upwards sending the air through the outlet valve 20 into the high pressure duct 10 and to the air turbine 12. The inlet valve 19 is closed.

In Figure 4, the wave trough 22 is below the power convertor 16 which now empties of water with the flexible membrane 18 drawn downwards and the inlet valve 19 opened for the power convertor 16 to re-fill with air at atmospheric pressure, ready for the cycle to repeat. The outlet valve 20 is closed.

Claims

PATENT APPLICATION NUMBER 8818498

CLAIMS 1 A network of flexible pipes comprising an interconnecting set of high pressure ducts and an interconnecting set of low pressure ducts, moored at sea, which is capable of conveying high and low pressure air into and out from an air-turbine which may be situated on the sea-bed or on a floating platform or on shore.
2 A network of flexible pipes as claimed in Claim 1 on which are mounted boxes constructed of rigid material on the sides and top and a flexible membrane at the bottom, each box having air valve connections into and out from the high and low pressure sides of the pipe network, so tha, with alternate submerging and emerging of the boxes as incident wave arrive, air is pumped round the network.

2 A network of flexible pipes as claimed in Claim 1 on which are mounted boxes constructed of rigid material on the sides and top and a flexible membrane at the bottom, each box having air valve connections into and out from the high and low pressure sides of the pipe network.

PATENT APPLICATION NUMBER 8818498 Amendments to the claims have been filed as follows 1 A network of flexible pipes comprising an interconnecting set of high pressure ducts and an interconnecting set of low pressure ducts, moored at sea, which is capable of conveying high and low pressure air into and out from an air-turbine which may be situated on the sea-bed or on a floating platform or on shore.