Modular floating breakwater for the transformation of wave energy

[0007] This is the 35 USC 371 national stage of International Application PCT/IT99/00287 filed on Sep. 14, 1999, which designated the United States of America and published as WO 01/20163 in English.

[0008] The present invention concerns a floating modular system for the protection of harbours and for the transformation of energy, with a self-levelling system for the anchorage with self-distributed traction and balancing of the tide variation and levelling between modules connected by means of couplings.

[0009] The present invention results from the need to protect the coasts even where there are no gulfs and bays, for the realization of harbour structures away from land protected by waves and independent of energy concerns.

[0010] The aim set forth is achieved by the apparatus according to the present invention which provides a system of coupled modules, self-levelled with respect to the anchorage and to the tide variations, having a plane structure perpendicular to the direction of the wave motion propagation in the high seas and therefore with a sinusoidal oscillation without backwash whirlpools, present in places where the soundings are deeper than half the maximum possible height of a wave, so as to reflect said waves for the complete protection of the opposed reaches of the coast, and comprising means for absorbing the energy of the wave motion transforming it into pneumatic and/or gravitational energy of waters pumped on the spot for the further transformation into electric energy.

[0011] The advantages of the present invention are many and remarkable:

[0012] the possibility of realizing floating harbour structures opposed to a coast, possibly without gulfs or bays;

[0013] the automatism in the anchorage levelling and with respect to the tide variations;

[0014] the possibility of obtaining a power autonomy and even an exceeding energy production;

[0015] the possibility of transporting the modules by marine traction and the possibility of composing the same with different dimensions;

[0016] it is ecological, as the whole system may be covered with cultivations so as to make it aesthetical similar to verdant islands;

[0017] the possibility, as a partial alternative to the preceding one, to obtain architectonic realizations supported by the floating modules.

[0018] The present invention will be explained more in detail herein below relating to the enclosed drawings in which an embodiment is shown.

[0019] FIG. 1 shows an axonometric scheme of a floating modular apparatus for the protection of harbours and for the transformation of energy.

[0020] FIGS. 2 and 3 show a lateral scheme of two variants of the means for transforming the wave motion energy into hydraulic gravitational and/or pneumatic energy.

[0021] FIG. 4 shows a possible system for the self-levelling of the floating modules' anchorage, with self-distributed traction.

[0022] FIG. 5 shows a possible system for balancing the tide variations and for levelling the modules.

[0023] FIG. 6 shows a plant scheme of a possible system of joints between the floating means.

[0024] The enclosed figures show a floating modular system for the protection of harbours and for the transformation of energy, comprising:

[0025] a plurality of modules 1, made of metal and/or reinforced marine concrete box-structure, comprising internal air spaces 2 for achieving floating of said modules, upper rooms 3 that can be exploited in different ways, and a lower flooded room 4 which, once filled with water, through openings 5, determines the lowering extent of the center of gravity of a given module and the floating stabilization under the impact of the waves against the level surfaces 6 for the reflection of the waves and the protection of the opposed harbour environment AP, provided with floating quays 7;

[0026] a series of floats 8 that will be operated by wave motion for absorbing wave energy with double effect pumps 9 for the accumulation of water at the top of the modules 1 and/or for operating pneumatic systems;

[0027] a self-levelling system for the anchorage of each of the modules 1, with self-distributed traction;

[0028] a system for balancing the tide variations and for levelling the modules 1;

[0029] a system of joints for coupling the modules 1 according to the extension required for the protection.

[0030] According to the details shown in FIG. 2, each float 8 operates, by means of a vertical rod 10, a piston 11 which, by means of valves 12, 13, 14 and 15 determines, in the rises and in the troughs of the wave, the suction of sea water in conduit 16 and the delivery through a pipe 17 to an accumulation reservoir contained 18 from which, thanks to gravity and operation of energy conversion means 33 such as hydraulic turbines and alternators, the transformation of the mechanic energy of the wave into electric energy is possible.

[0031] In the variant shown in FIG. 3, said floats 8 have been replaced by hollow structures in the shape of a bell 19, in which the liquid mass of the sea wave has the function of a liquid piston for moving the air collected by an upper pair of bellows 20, by means of a valve 21, and the further delivery thereof, by means of a valve 22, to a duct provided with energy conversion means 34 such as a pneumatic impeller, also operating an alternator or similar, for the production of electric energy.

[0032] The self-levelling system shown in FIG. 4 comprises one single rope 23 which, starting from the self-blocking winch 24 through pulleys 25, is joined to anchorage points 26 and allows, due to its movement, the adjusting of the level of the modules during installation as well as during changes of the tide level.

[0033] Furthermore, said system determines the automatic distribution of the load onto said anchorage points 26, in a static or dynamic position in each module 1, even in case or sudden overload in extreme points. This avoids to overload only one anchorage point thus preventing its breaking or the breaking of the rope.

[0034] For quickly replacing said rope 23, due to regular maintenance or to wear, two parallel ways may be taken: in one, the traction rope must slide and in the second one, a cable is used at the same moment of replacement of said rope.

[0035] In an embodiment of the system according to the present invention, the sliding points of the rope consist of fixed half pulleys 25 with conical opening for housing the emergency blocking device for a broken rope. Said system is arranged at a distance calculated according to the maximum lift of the coupling hinges between the modules.

[0036] In case of casual breaking of the rope, the blocking system allows to put out of use just one portion thereof while the remaining part of the rope will continue to work, allowing the module to be lifted only a few centimeters; in this case, no damage will occur to the structure, and it will be possible to quickly replace the rope.

[0037] The replacing of the rope takes place in the room in which said winch(es) 24 is (are) arranged. The top end the bottom of the rope is provided, according to the present invention, with a self-blocking system with conical housing and with big damping springs. The installation of the rope from the top has three advantages:

[0038] during installation, the underwater work is limited;

[0039] the traction of the rope may be constantly controlled;

[0040] the rope may be replaced at any moment, even during rough sea.

[0041] The balancing system shown in FIG. 5 provides a dose chamber 2′ in each module 1, containing water and air; water is let in through ducts 27 while air is pumped in by means of a compressor 28 so that, by adjusting the quantity of water in the chamber, the lowering or lifting of said floating module 1 is obtained.

[0042] Depending upon variation of the sea according to the tide, the air volume required for keeping the module 1 lifted and therefore in a stable position during low tide will be calculated. The stress of the rope will be calculated taking into account the draught during high tide.

[0043] The described system allows to lift and lower each module 1 obtaining four remarkable advantages:

[0044] for performing the anchorage, after having fixed the rope, a module 1 is lifted discharging water until it reaches the same level as the other modules;

[0045] loading and discharging water the exact tension of the rope is obtained, and a plurality of modules may be hinged at the same time without great effort;

[0046] each module 1 is independent and therefore no particular device is required for placing it.

[0047] The coupling system between said modules 1 as shown in FIG. 6 consists of two parts: a housing 29, to be positioned on said module 1, and a movable part.

[0048] Said housing 29 is closed with a bracket 30 after having inserted a joint 31, realized with a cross-shaped system so as to perform vertical as well as horizontal movements; the ends thereof consist of two plates housed in said module 1.

[0049] The empty space between said modules 1 may receive two hard rubber cushions 32: or similar which have the function of dampening the bumps and not allowing the passage of portions of waves to the opposite part of the module. necessary The coupling system described above has proved to be necessary for increasing the safety of the system in case of loosening in the anchorage system or of modest pitching due to sudden overload on the extreme points of each module.

[0050] Finally, in case of anomalous frequencies and heights in the bumps against the whole front of said modules 1, a dampened reaction would occur avoiding the breaking of the couplings.