IE20020856A1 - Power generation - Google Patents

Abstract

A tidal pumped storage power generation arrangement and method, comprising first and second basins (100, 200), the first basin (100) being vulnerable to tides and the second basin (200) being sealed, both of said basins having at least one electrical power generation means (6,7,8) associated therewith, whereby the electrical power generation means (6) associated with said first basin (100) is arranged to operate while the tide is rising or falling, the arrangement further comprising means for causing water to flow directly from said first basin (100) into said second basin around high tide, and means for causing water to flow directly from said second basin (200) into said first basin (100) around low tide, such that the electrical power generation means (8) associated with said second basin (200) operates around high and low tide. <Figure 1>

Description

This invention relates to power generation and, more particularly, to power generation using tidal and pumped storage water.

There have been many different proposals for the use of tidal energy to generate electrical power. For example, GB Patent No. 283,607 describes an arrangement consisting of three sea basins? an auxiliary basin, a first basin I and a second basin Π, the three basins being separated from each other by means of walls. The method of power generation employed in this proposed arrangement follows a very specific cycle, as follows? a) when the sea level is above a so-called mean position, water flows into basin I (via the auxiliary basin) until it reaches a mean position therein; b) then basin II (which is above the mean position because it was filled and then sealed during a previous high tide) is discharged into the sea (again via the auxiliary basin); c) when the level in basin I (from step a)) is higher than sea level (because the tide is going out), basin I is discharged into the sea (via the auxiliary basin); d) finally, discharge from basin Π to the sea (via the auxiliary basin) is recommenced.

There are numerous other known arrangements which employ one or more sea basins, so as to employ tidal energy to generate electrical power. However, in the case where there is only one sea basin, power generation is vulnerable to the tides, and power cannot therefore be generated continuously. On the other hand, where there are two or more scaw basins employed, although this problem Is at least partially overcome, the resultant arrangements tend to be relatively complicated and inefficient.

I have now devised an arrangement which overcomes these problems. Thus, in accordance with the present invention, there is provided a tidal pumped storage power generation arrangement, comprising first and second basins, the first basin being vulnerable to tides and the second basin being sealed, both of said basins having at least one electrical power generation means associated therewith, whereby the electrical power generation means OPEN TO PUBL'C INSPECTION UNDER SECTION 28 ANL RULE 23 -2IE Ο 2 Ο 8 5 6 associated with said first basin is arranged to operate while the tide is rising °r falling, the arrangement further comprising means for causing water to flow directly from said first basin into said second basin around high tide, and means for causing water to flow directly from said second basin into said first basin around low tide, such that the electrical power generation means associated with said second basin operates around high and low tide.

Also in accordance with the present invention, there is provided a method of electrical power generation, comprising the steps of providing or creating first an second basins, the first basin being vulnerable to tides and the second basin being sealed, providing respective electrical power generation means for operation in association with each of said basins, causing the electrical power generation means associated with said first basin to operate while the tide is rising or falling, causing water to flow directly from said first basin into said second basin around high tide, and causing water to flow directly from said second basin into said first basin around low tide, thereby causing the electrical power generation means associated with said second basin to operate around high and low tide.

Thus, the present invention provides a simple and efficient tidal and pumped storage power generation arrangement and method, which utilises tidal power when it is available and pumped storage power around high and low tides, so as to enable substantially continuous power generation.

In a preferred embodiment of the present invention, the first and second basins are defined by two sea walls or dams, a first sea wall or dam being provided between two land points or similar permanent fixtures, and the second sea wall or dam being provided between a point on said first sea wall or dam and a third land point or similar permanent fixture.

Thus, the first sea wall or dam preferably defines a single large basin, while the second sea wall or dam divides the basin into the first and second basins.

Beneficially, electrical power generation means, such as a tuibine or paddle wheel, is provided between the first basin and the tidal body of water in which the arrangement is to be operated, between the second basin and the same tidalbody of water, and between the ΙΕ ο 2 08 5 8 -3first and second basins. A lock may also be provided between the first basin and the tidal body of water to enable access between the two by vessels.

Thus, in accordance with this arrangement, as the fide rises, the electrical power generation means between the tidal body of water and the first basin is preferably activated, while the other two electrical power generation means are sealed. When the flow of water becomes relatively slow, around high tide, one or both of the other two electrical power generation means may be activated, and water caused to flow from the first basin into the second basin. At high fide, file electrical power generation means between the first basin and the tidal body of water is preferably sealed, and water continues to flow from the first basin into the second basin through the associated electrical power generation means. Water may also be caused to flow from the second basin into the tidal body of water through the associated electrical power generation means. This continues until the tide starts to go out again. As the tide falls, the electrical power generation means between the first basin and the tidal body of water is activated and the other two electrical power generation means are preferably sealed, until the flow of water becomes relatively slow, around low tide, when one or both of these electrical power generation means is once again activated. At low tide, the electrical power generation means between the first basin and the tidal body of water is sealed, and water is caused to flow from the second basin into the tidal body of water through the associated electrical power generation means. When the tide has risen sufficiently once again, the electrical power generation means between the first basin and the tidal body of water is once again activated and the other two electrical power generation means are sealed, and the cycle begins once again.

Embodiments of lhe present invention will now be described by way of examples only and with reference to the accompanying drawings, in which: Figure 1 is a schematic diagram illustrating a tidal and pumped storage power generation arrangement according to a first exemplary embodiment of the present invention; ΙΕ ο 2 ο 8 5 8 -4Figure 2 is a schematic diagram illustrating a tidal and pumped storage power generation arrangement according to a second exemplary embodiment of the present invention; and Figure 3 is a schematic diagram illustrating a tidal and pumped storage power generation arrangement according to a third exemplary embodiment of the present invention.

Referring to Figure 1 of the drawings, a coastal inlet, cove or bay is illustrated, across which is provided a sea wall or dam 10 between land points 2 and 3. A second, preferably stronger, sea wall or dam 20 is provided between point 4 on the first wall 10 and another land point 5. As shown, the two walls 10,20 together define two sea basins 100,200.

A lock 9 with gates 12,13 is provided in the wall 10 to enable navigation of vessels from the main body of water into the first sea basin 100, as required. Paddle wheels 6,7 are provided in the wall 10 on either side of the point 4, one associated with each of the two sea basins 100,200 respectively. A third paddle wheel or turbine is provided in the second wall 20, between the first and second sea basins 100,200.

The arrangement operates as follows: 1) When the tide is rising, the paddle wheel or turbine 6 associated with the sea basin 100 (which is vulnerable to the tides) rotates and generates electrical power. The second sea basin 200 is isolated iron this rising tide by the other two paddle wheels or turbines 7, 8. 2) When the tidal water starts to flow relatively slowly, as high tide approaches, the paddle wheel or turbine 7 and/or the paddle wheel or turbine 8 may be activated. In this case, water from the tidal sea basin 100 is caused to flow into the sealed basin 200, thereby causing the paddle wheel or turbine 7 to rotate and generate electrical power. ΙΕ ϋ 2 08 5 6 -53) At high tide, the turbine or paddle wheel 6 is sealed to separate sea basin 100 from the Idee, river, sea or ocean in which the arrangement is being operated. 4) When the tide starts to recede, the paddle wheel or turbine 6 can be restarted, such that water from the sea basin 100 starts to flow out into the lake, river, sea or ocean in which the arrangement is being operated, and paddle wheel or turbine 8 is sealed. It will be appreciated that the turbine or paddle wheel 6 will now be rotating in an opposite direction to that in step 1), but this can be relatively easily overcome by, for example, providing a reverse gear, changing the polarity of the generator or by rotating the turbine or paddle wheel horizontally through 180°.

) When the tidal water once again starts to flow relatively slowly, as low tide approaches, paddle wheel or turbine 7 is activated and water flows from the sealed basin 200 into the lake, river, sea or ocean in which the arrangement is being operated. The paddle wheel or turbine 7 is sealed at low tide, when the basin 200 is empty. 6) As the tide rises once again, paddle wheel or turbine 6 is sealed and components 7 and/or 8 are restarted until the tide has risen enough for the paddle wheel or turbine 6 to be started and components 7 and/or 8 to be sealed to keep the water in the basin 200 low, so as to allow for transfer of water from the sea basin 100 to the sea basin 200 at high tide through paddle wheel or turbine 8 or from the sea through paddle wheel or turbine 7. This completes the cycle, which then returns to step 1).

Figures 2 and 3 illustrate arrangements which operate in substantially the same way as set out above, although their configuration is somewhat different because of the shape of the land mass around which the arrangement is to be positioned. It will be appreciated that the longer the sea wall 10 is requited to be, the more expensive the arrangement is likely to be to construct. However, this does not adversely affect the operation of the arrangement.

IE Ο 2 08 5 β Embodiments of the present invention have been described above byway of examples only, and it will be appreciated by a person skilled in the ait that modifications and variations can be made to the described embodiments without departing from the scope of the invention as defined by the appended claims.

Claims (14)

Claims

1. A tidal pumped storage power generation arrangement, comprising first and second basins, ±e first basin being vulnerable to tides and the second basin being sealed, both of said basins having at least one electrical power generation means associated therewith, whereby the electrical power generation means associated with said first basin is arranged to operate while the tide is rising or falling, the arrangement further comprising means for causing water to flow directly from said first basin into said second basin around high tide, and means for causing water to flow directly from said second basin into said first basin around low tide, such that the electrical power generation means associated with said second basin operates around high and low tide,

2. An arrangement according to claim 1, wherein the first and second basins are defined by two sea walls or dams.

3. An arrangement according to claim 2, wherein a first sea wall or dam is provided between two landpoints or similar permanent fixtures, and a second sea wall or dam is provided between a point on said first sea wall or dam and a third land point or similar permanent fixture.

4. An. arrangement according to any one of the preceding claims, wherein electrical power generation means, such as a turbine or paddle wheel, is provided between the first basin and a tidal body of water in which the arrangement is to be operated, between the second basin and the same tidal body of water, and between the first and second basins.

5. An arrangement according to any one of the preceding claims, wherein a lock is provided between the first basin and a tidal body of water to enable access between the two by a vessel or the like. IE02 0856 -86. An arrangement according to claim 4, wherein, as the tide rises, the electrical power generation means between the tidal body of water and the first basin is activated.

6. 7. An arrangement according to claim 6, wherein the other two electrical power generation means are sealed as the tide rises.

7. 8. An arrangement according to claim 7, when the flow of water becomes relatively slow, around high tide, one or both of the electrical power generation means between the first and second basins and between the second basin and the tidal body of w'ater is/are activated, and water caused to flow from the first basin into the second basin.

8. 9 An arrangement according to claim 8, wherein at high tide, the electrical power generation means between the first basin and the tidal body of water is sealed, and water continues to flow from the first basin into the second basin through the associated electrical power generation means.

9. 10. An arrangement according to claim 9, wherein water is caused to flow from the second basin into the tidal body of water through the associated electrical power generation means.

10. 11. An arrangement according to claim 10, wherein as the tide falls, the electrical power generation means between the first basin and die tidal body of water is activated and the other two electrical power generation means are sealed.

11. 12. An arrangement according to claim 11, wherein when the flo.w of water becomes relatively slow, around low tide, one or both of fire electrical power generation means between the first and second basins and between the second basin and the tidal body of water is/are once again activated. -913. An arrangement according to claim 12, wherein at low tide, the electrical power generation means between die first basin and the tidal body of water is sealed, and water is caused to flow from the second basin into the tidal body of water through the associated electrical power generation means.

12. 14. A tidal pumped storage power generation arrangement substantially as herein described with reference to the accompanying drawings.

13. 15. A method of electrical power generation, comprising the steps of providing of creating first an second basins, the first basin being vulnerable to tides and the second basin being sealed, providing respective electrical power generation means for operation in association with each of said basins, causing the electrical power generation means associated with said fust basin to operate while the tide is rising or falling, causing water to flow directly from said first basin into said second basin around high tide, and causing water to flow directly from said second basin into said first basin around low tide, thereby causing the electrical power generation means associated with said second basin to operate around high and low tide.

14. 16. A method of electrical power generation substantially as herein described with reference to the accompanying drawings.