EP2087231A1

EP2087231A1 - Wave energy recovery device

Info

Publication number: EP2087231A1
Application number: EP06841867A
Authority: EP
Inventors: José-Antonio Ruiz-Diez; Diégo Ruiz
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-12-06
Filing date: 2006-12-06
Publication date: 2009-08-12
Also published as: BRPI0622188A2; US20110008106A1; CN101617119A; WO2008068390A1; MX2009006006A

Abstract

A device for recovering the energy of sea waves, which comprises at least one floating structure intended to float on the surface of the water. Said floating structure carries at least one member (2) suspended above the surface of the water, the structure of which is designed to generate recoverable energy through the variation in height of the surface of the water relative to said member, under the effect of the ascending and descending movement of the waves. Application to recovering wave energy.

Description

Device for recovering the energy of the swell.

The present invention relates to a device for recovering the energy of waves on a body of water, such as at sea.

At present, energy consumption is mainly based on non-renewable energies such as oil, gas, coal and nuclear power. Given the depletion of reserves in these energies and / or the pollution generated by their use, we seek to diversify the sources of energy, turning in particular towards renewable energies.

In this context, one solution is to use the energy from the sea, more precisely in terms of currents, swell or tide.

Thus, wave energy is only a particular form of solar energy. The sun heats unevenly the different atmospheric layers which causes air currents (winds) themselves responsible by friction of the movements that animate the surface of the sea (currents, waves, waves).

The waves created by the wind on the surface of the seas and oceans carry energy. When they arrive on a floating or coastal obstacle, they can give up some of this energy, which can be transformed into electric current. This is where the winds are the strongest, between 40 ° and 60 ° of latitude, that the power of the waves is maximum.

As a result, wave energy has a very high power potential. Thus, the average power transported by the waves is given in kW per linear meter. It is proportional to the wave period (the time that separates the arrival of two successive wave peaks) and to the square of the height of the wave (distance between the hollow and the ridge). For example, this potential is 63 kW / m off Ouessant, 50 kW / m on the Atlantic coast and 8 kW / m in the Mediterranean. Wave energy is also characterized by the energy that occurs during a year over a linear meter of installation. For example, on the French Atlantic coast this potential is 420 MWh / m. On 1000 km of Atlantic coast the annual energy transported by waves is 420 TWh, it is the order of magnitude of the total electrical energy consumed in France each year.

However, this total resource can not be fully exploited especially given technical limitations and natural or legal limitations that reduce the usable area.

Many devices have already been proposed, which can be classified into two broad categories: coastal devices and open sea devices.

The former use wave breaking, the latter use sea-level variations during the passage of waves. The former are easy to build and maintain, but their performance is not as good as offshore devices that exploit more powerful and more consistent waves.

Thus, EP 1 295 031 discloses a device based on the movement of a buoy, the device comprising an outer round float surrounding an inner float, these two floats being connected to each other by connecting means comprising in particular hydraulic cylinders allowing the recovery of the energy of the movement between the two floats and further having a submerged body.

There is also known a mobile cylinder (the float) filled with air that slides on a cylinder fixed to the bottom of the sea. In the absence of wave the float is in equilibrium. When the top of the wave passes over the float the overpressure depresses the float. In the hollow of the wave the depression makes the float rise. The comings and goings of the float relative to the fixed cylinder causes a linear dynamo producing electric current. This device however has the disadvantage of having to be fixed in part at the bottom of the sea. The present invention therefore aims to provide a device for the recovery of wave energy whose simpler structure facilitates the use and implementation.

Thus, the subject of the present invention is a device for recovering the energy of waves at sea, comprising at least one floating structure intended to float on the surface of the water, characterized in that the said floating structure carries at least a member suspended above the surface of the water whose structure is arranged to generate a recoverable energy during the variation of the height of the surface of the water with respect to said body, under the effect of the upward movement and descending from the swell.

Very advantageously, a device according to the invention allows, by cooperation of the structure of said organ with the surface of the water, to recover energy up to two times or more that of the height of the wave and / or that of the speed of the wave.

Advantageously, according to one embodiment, the floating structure is preferably composed of at least two floating elements such that beams extending substantially parallel to each other, one said before and the other said rear and between which extends substantially projecting upwardly, at least one bridge amount between said float elements, the at least one suspended member being fixed on said upright so as to extend substantially perpendicular to said float elements and substantially equidistant from them.

Preferably, the floating structure has a length defined by the length of the front and rear float elements, less than the spacing between said front and rear float elements, said front and rear float elements being positioned parallel to the waves, in optimum operating position at the surface of the water, the axis connecting the float elements thus being substantially perpendicular to the waves.

Preferably, the spacing between the front and rear float elements can be adjustable by any suitable means. In this way, it is possible to adapt the spacing between the front and rear float elements so that it corresponds to a wavelength of wave, a wave being thus trapped between the two float elements. Of course, the spacing between the float elements can be fixed.

Preferably, the floating structure further comprises appropriate means to allow the positioning of said structure on the surface of the water in an optimal position, that is to say so that the front and rear float elements are parallel to the waves.

Thus, these means may consist of at least one keel carried by the floating structure, preferably the keel being provided connected to each float element.

Such means may also consist of at least one wind-holding element carried by the floating structure orienting said floating structure facing the wind so that the float elements are parallel to the waves.

According to an alternative embodiment of the invention, the floating structure consists of at least four floating elements such as floating beams, connected to said member.

Similarly, according to another variant embodiment, the floating structure consists of at least four float elements such as float elements carried at the end of uprights, said float elements being connected to said member by said uprights, two float elements. being told before and the other two said back.

Thus, it defines two float elements carried by amounts, said before and said two rear, t alignment of the front float elements and the alignment of the rear float elements being parallel to each other, and in the optimal operating position of the device, parallel to the waves.

Preferably, at least one of the float elements before said floating structure can be oriented with respect to a vertical axis of said float element so that said front float element can not extend parallel to the other float element. before, the axis that connects them being always substantially parallel to the waves. This is particularly the case when the float elements have for example an elongated shape such as a beam.

Preferably, the floating structure of the device according to the invention is arranged to be attached to a buoy, an anchor; but it can also be towed by a boat, propelled or self-propelled or others from the front to facilitate its positioning in front of the waves so that the front and rear float elements or their alignment are parallel to the waves.

According to a first embodiment of the invention, said suspended member carried by said floating structure comprises a float element intended to float on the surface of the water, this float element being connected by at least one flexible connecting element such as a chain, a sling, a cable, to means which are arranged to generate energy either in electrical form or in the form of a compressed fluid, under the effect of at least traction, exerted on the element flexible connection by at least the downward movement of the float element under the effect of the movement of the swell.

Preferably, the means for generating the energy in the form of electric current are such that a dynamo whose rotation drive to generate electrical energy intervenes under the effect of a traction exerted by the float element on the flexible connecting element for example wound on the dynamo. It also makes it possible to produce electrical energy directly from the movement of the swell.

The wave energy can be recovered, at least during the traction exerted on the flexible connecting element, by means of energy generation in the form of compressed fluid, releasable by conventional means or to generate energy. electrical energy by using compressed fluid in the form of pneumatic, hydraulic energy.

According to a second embodiment, said member defines at least in part an enclosure whose volume is variable as a function of the height of the surface of the water, therefore of the swell, the compression of a fluid contained in said generating volume recoverable energy. Preferably, the member carried by the floating structure is an enclosure having an open lower end and a closed upper end, said enclosure being fixed to the floating structure on the closed end side so that its open end is immersed, the water entering the volume defined by said closed cylinder, so that, under the effect of the swell, the height of the water in the enclosure thus defined may vary causing the variation of the volume of said enclosure and generating in particular a compression air trapped inside, recoverable later to generate energy.

According to a variant of this embodiment, there may be provided a float engaged in said enclosure for regulating the rise of water and the pressurization of the air in said enclosure. In addition, this float also makes it possible to recover the energy generated by the descent of the weight of said float as soon as the water descends faster than it.

The compressed air in said enclosure can be used directly in the form of pneumatic energy or used to generate electricity. This recovered compressed air is in fact subsequently recovered and used by appropriate conventional means.

Such a device according to the invention may advantageously be used at sea to allow in particular the power supply of sites such as fish farms or for any other use at sea and on bodies of water on land (lake, river, river, pond) requiring electrical, hydraulic and / or pneumatic energy.

In addition, even more preferably, the floating structure comprises at least one wind turbine, preferably of fixed orientation. It is thus also possible to recover the energy of the wind at the level of the floating structure to convert it into energy, in particular electrical energy.

The invention will now be described in more detail with reference to the drawings in which:

Figure la shows a cross-sectional view of a first embodiment of the device according to the invention, the wave being high between the float elements of the floating structure; Figure Ib shows a view according to Figure la the wave being low between the float elements of the floating structure;

Figure 1c shows a top view of the device of Figure 1a;

Figure Id shows a sectional view of a variant of the device of Figure la;

Figure 2 shows a sectional view of a second alternative embodiment of the device of Figure 1a;

FIG. 3 represents a sectional view of a third variant embodiment of the device of FIG.

FIG. 4 represents a sectional view of a fourth variant embodiment of the device of FIG.

FIG. 5 represents a cross-sectional view of a fifth variant embodiment of the device of FIG.

Figures 6a and 6b respectively show a sectional view and a top view of a second embodiment of a device according to the invention;

Figures 7a and 7b respectively show a sectional view and a top view of a variant of the device of Figures 6a and 6b;

Figure 8a shows a cross-sectional view of a third embodiment of a device according to the invention, the wave being high between the float elements of the floating structure of the device;

Figure 8b shows a sectional view of the device of Figure 8a; the wave being low, between the floating elements of the floating structure of the device; Figure 8c shows a top view of the device of Figure 8a;

Fig. 8d shows a sectional view at the line A-A of Fig. 8c, and

Figure 9 shows an alternative embodiment of the device shown in Figures 8a to 8d.

The device according to the invention shown in FIGS. 1a, 1b and 1c has a floating structure consisting of two float elements 1, such as beams extending substantially parallel to each other and to the waves and between which extend bridge posts 3 between said float members 1, 1 '.

A member 2 such as a fixed enclosure suspended on each upright 3 extends substantially perpendicular to the sea level to said beams 1, 1 'and substantially equidistant therefrom. This cylindrical chamber of circular section closed at one end 2a is fixed to an upright 3 at said closed end 2a while its open end is immersed. This member 2 thus defines an enclosure whose volume A is variable as a function of the swell, that is to say the level of water entering said enclosure 2.

In order to be able to best recover the energy of the waves, the optimal positioning of the device is such that the float elements 1, 1 'are parallel to the waves, one 1 being at the front and the other the at the rear in the direction of the swell represented by the arrow H in Figures la and Ib.

Preferably, the spacing between the float elements 1, 1 'corresponds to a wave wavelength, a wave being thus trapped between the two float elements 1, 1', as can be seen in FIG.

In FIG. 1a, the float elements 1, 1 'are therefore in wave recesses and the member 2 located between said float elements 1, is approximately at a wave crest so that the level of water in the enclosure is maximum, which generates the reduction of the volume A 'and therefore the compression of a fluid such as the air enclosed in said volume. This compression of the air generates a recoverable energy. In particular, the compressed air leaves said compression chamber A 'thus formed through a non-return valve 6 provided at the end 2a of the chamber 2 which only allows air to pass after that a certain pressure has been reached in said compression chamber A 'thus formed.

Then, when the member 2 is in a wave recess, the water level drops back into the chamber which resumes a normal volume A. This results in a theoretical race double that of the wave height (see Figure Ib).

To increase the stability of the floating structure, it is conceivable that the beams 1, 1 contain a certain amount of water.

Any complementary means of support of the enclosure 2 may be provided such as slings or rigid arms 4.

In Figure Id, a device according to Figure la is shown and further comprises a second member 5 defining an enclosure whose volume is variable under the effect of the swell. This member 5 is in the form of a conical wall chamber forming a funnel and extending from a beam 1 perpendicular to it on the surface of the water. A check valve 6 'is also provided for recovering the compressed air. This further improves the energy recovery. This member 5 can be installed for example between two speakers 2.

FIG. 2 shows an alternative embodiment of the device of FIG. 1a in which the member 2 is furthermore provided with a float 7 inside the enclosure defined by said member 2. This float 7 makes it possible to regulate the rise of water in the enclosure.

In Figure 3, the member 2 further comprises an orifice in its upper part through which is engageable a rod 7b formed projecting from a float 7.

In Figure 4, the member 2 also has a tubular projection 2c in which is housed the rod 7b formed projecting from the float 7. This defines a first chamber A and a second chamber B, chamber A thus defined may be at atmospheric pressure and chamber B may be at an additional pressure.

In Figure 5, there is shown an alternative embodiment of the floating structure in which tubular or other uprights 30 extend between the beams 1 on either side of a member 2 to maintain it.

At least one non-return valve 6 is provided at each member 2 (FIGS. 2, 3, 4, 5) to allow the passage of air only after a certain pressure has been reached in said compression chamber formed in each enclosure 2.

The floating structure can also be made so as to be organized around the body defining the enclosure, the floating structure thus comprising the suspended member. Thus, as can be seen in FIGS. 6a and 6b, for example four beams 10, 10 'extend perpendicularly to said cylinder 2 forming a floating cross structure. The spacing between the beams 10, 10 'can be adjusted by any appropriate means.

Alternatively, uprights 8 extend from the chamber 2 and are provided with float elements 9, 9 'at their ends. As can be seen in Figures 7a and 7b.

Again, the optimal operating position of the device consists of having two beams 10 at the front and two beams 10 'at the rear or two float elements 9 said before and two float elements 9' said rear relative to the direction of the swell.

Thus, the two float elements 9 substantially aligned at the front with each other and the two float elements 9 'substantially aligned at the rear with each other will respectively be substantially parallel to the waves in the operating position optimal, the device comprising appropriate means to allow optimal positioning such as those mentioned above. However, one of the forward float elements 9 may be steerable with respect to a vertical axis of said float member 9 so that said forward float member 9 may not extend parallel to the other rear float member 9, their alignment remaining preferably parallel to the waves. In addition, the spacing between the float elements 9 before and the rear float elements 9 'can be adjustable or fixed.

Preferably, the length of the floating structure defined by the gap between the front and rear float elements may be greater than the spacing defined between the front and rear 9 and 9 front float elements.

In the embodiment shown in Figures 8a to 8d, the upright 11 extending between the beams forming float members 1, V is substantially vertical V-shaped upside down.

The member carried by the floating structure consists of a piston 12 whose free end is fixed to the floating structure, in this case at the tip of the bridge amount of the floating structure. The other piston end is engaged in a cylinder 13, said cylinder 13 being connected at its other end to a member 14 such as a counterweight float shaped to float on the surface of the water. This float counterweight 14 is arranged to exert a quasi-permanent traction force towards the surface of the water. It is preferably positioned closer to the float element 1 before the floating structure.

Similarly, the floating structure may be provided with means for hoisting the float 14 above the surface of the water during a storm. Indeed, it is preferred to disable the device according to the invention in case of storm as a point of view of the waves that take hold in the air.

Thus, when on the crest of a wave, the cylinder 13 extends around the piston rod 12 (see Figure 8a). When passing through a wave recess (FIG. 8b), the cylinder 13 driven by the float 14 sufficiently heavy to float on the surface of the water or air slides along the piston 12 and this sliding allows driving a dynamo, for example, through a chain on which the cylinder exerts traction. The piston and the cylinder serve advantageously to guide the cable, to limit the swinging movement of the counterweight float 14.

Conversely, the member carried by the floating structure consists of a cylinder whose end is fixed at the apex of a bridge member of the floating structure and whose other end engages a piston said piston being connected at its free end to a member such as a counter-weight float, shaped to float on the surface of the water, said piston during its sliding along the cylinder under the effect of the swell actuating an electrical energy generating member, for example.

To stabilize the floating structure, there are also spacers 15 between the beams 1 and a spacer 16 between the vertices of the uprights 11 or any other appropriate means.

In this embodiment, the floating structure may consist of two boats in place of the floating beams connected by an inverted V-shaped bridge structure, the rod and the cylinder being connected to a third boat forming the float 14.

The elements constituting the device according to the invention are made of any suitable materials including composite materials, steel, aluminum, etc.

In the variant shown in FIG. 9, the floating structure comprises a funnel-shaped member 25, 25 'arranged to channel the waves in a closed corridor from below by means of a plate 27 extending from a front float element. 1 to the space between the two float elements 1.1 'of the floating structure. This funnel member preferably consists of side walls 25 extending from the float members 1 to the suspended member, here the float 14, vertically relative to the plate 27 to define a channel tapering to the float 14 and then then widening 25 'to the rear float element V, thereby increasing the height of the waves at the float counterweight 14 or an enclosure 2. This member 25, 25' is further adjustable. Preferably, the floating structure is arranged to be attached, propelled or self-propelled from the front, to facilitate its positioning facing the waves so that the float elements 1, l '; 9, 9 'are always at maximum parallel to the waves.

Naturally, the invention is not limited to the examples described but covers all the embodiments covered by the set of claims.

Claims

1. A device for recovering wave energy at sea, comprising at least one floating structure intended to float on the surface of the water, characterized in that said floating structure carries at least one member (2, 14) ) suspended above the surface of the water whose structure is arranged to generate a recoverable energy when the height of the surface of the water varies with respect to said body, under the effect of upward and downward movement of the swell.

2. Device according to claim 1, characterized in that the floating structure is preferably composed of at least two float elements (1, l ') such that beams extending substantially parallel to each other, one (1) said front and the other (1 ') said rear, and between which extends substantially projecting upwards, at least one amount (3, 30, 11) forming a bridge between said float elements (1 , l '), the at least one member (2) being fixed on said upright so as to extend substantially perpendicular to said float members (1, 1') and, preferably, equidistant therefrom.

3. Device according to claim 1, characterized in that the floating structure consists of at least four float elements such as floating beams (10, 10 '), connected to said member (2).

4. Device according to claim 1, characterized in that the floating structure consists of at least four float elements, such as float elements (9, 9 ') carried at the end of uprights (8), said float elements (9, 9 ') being connected to said member (2) by said uprights (8), two float elements (9) being said before and the other two (9') said rear.

Device according to claim 4, characterized in that at least one of the front float elements (9) is orientable with respect to a vertical axis of said float element (9) so that said float element (9) can not not extend parallel to the other float element (9).

6. Device according to one of claims 2 to 5, characterized in that the spacing between the front float elements (1; 9) and rear

(V,; 9 ') is adjustable, preferably over a medium wave wavelength.

7. Device according to one of claims 2 to 5, characterized in that Pécartemenl between the front and rear float elements (1, l '; 9, 9') is fixed.

8. Device according to one of claims 2 to 7, characterized in that the floating structure further comprises appropriate means to allow the positioning of said structure on the surface of the water so that the front and rear float elements ( 1.1 ', 9, 9') are parallel to the waves.

9. Device according to claim 8, characterized in that these means consist of at least one keel carried by the floating structure, preferably the keel being provided connected to each float element (1,1 '; 9, 9'). .

10. Device according to claim 8, characterized in that such means consist of at least one wind catching element carried by the floating structure directing said floating structure when it is on the surface of the water facing the wind of so that the front (1; 9) and rear (1 '; 9') float elements are parallel to the waves.

11. Device according to one of claims 1 to 10, characterized in that the member carried by said floating structure comprises a float element (14) intended to float on the surface of the water, this float element being connected by at least one flexible connecting element such as a chain, a sling, a cable, to means which are arranged to generate energy at least under the effect of traction, exerted on the flexible connecting element at least by the downward movement of the float element under the effect of the movement of the swell.

12. Device according to claim 11, characterized in that the member carried by the floating structure consists of a piston (12) whose free end is preferably fixed to the floating structure and the other end piston (12) is engaged in a cylinder (13), said cylinder (13) being connected at its other end to a member (14) shaped to float on the surface of the water, said cylinder during its sliding along the piston under the effect of the swell operating an energy generating member such as in electrical form in the form of compressed fluid.

13. Device according to one of claims 11 to 12, characterized in that the current generating means are such that a dynamo whose rotational drive to generate electrical energy occurs under the effect at least d a traction exerted by the float element on the flexible connecting element as wound on the dynamo.

14. Device according to one of claims 1 to 10, characterized in that said member defines at least in part an enclosure whose volume is variable depending on the height of the surface of the water, so the swell, the compressing a fluid enclosed in said volume generating recoverable energy.

15. Device according to claim 14, characterized in that the member carried by the floating structure is an enclosure (2) having an open lower end and a closed upper end (2a), said enclosure (2) being fixed to the structure floating on the side of its closed end (2a) so that its open end is immersed, the water entering the volume defined by said closed enclosure, so that, under the effect of the swell, the height of the water in the enclosure thus defined may vary causing the variation of the volume of said enclosure and generating in particular a compression of air enclosed in recoverable next to generate energy.

16. Device according to claim 15, characterized in that a float (7) is engaged in said enclosure for regulating the rise of water and the pressurization of the air in said enclosure.

17. Device according to one of claims 1 to 16, characterized in that it further comprises a member (5) in the form of a conical wall chamber forming a funnel and preferably extending from a float element (1 ') perpendicular to the latter on the surface of the water, making it possible to recover the compressed air by the height and speed of a wave, directly or via a piston, at using a non-return valve (6 ').

18. Device according to one of claims 1 to 17, characterized in that the floating structure comprises a member (25, 25 ') forming a funnel arranged to channel the waves in a closed corridor from below with the aid of a plate 27 extending from a front float member 1 to the space between the two float members 1,1 'of the floating structure, said funnel member being constituted by side walls (25) extending from the float members 1 to the suspended member (14), vertically relative to the plate (27) to define a channel narrowing down to said member (14) and then widening (25 ') thereafter towards the rear float member (1'), this member (25, 25 ') being further adjustable.

19. Device according to one of claims 1 to 18, characterized in that the floating structure is arranged to be attached, towed, propelled or self-propelled from the front, to facilitate positioning against the waves so that the front float elements and back are parallel to the waves.

20. Device according to one of claims 1 to 19, characterized in that the floating structure further comprises at least one wind turbine preferably fixed orientation to produce electricity.