Title of Invention

A POWER GENERATION APPARATUS

Abstract

A power generation apparatus for generation of power from the energy present in waves in an ocean, comprises: a) at least one stationary platform (E) located above mean sea level, with its length oriented substantially parallel to predominant wavefronts at the site; b) a plurality of floats (L) suspended from longer side of that platform so that top of each float remains above the water line, the floats being spaced apart along the longer side of the platform; c) three pulleys (HI, U, H2) for each float, the pulleys being mounted on the platform with a steel wire rope (K) passing over each outer pulley (HI, H2) and wound once around the middle pulley (J); d) each float being attached to one free end of the steel wire and a counterweight (M) of half the weight (W) of the float being attached to the other free end of the steel wire rope; e) a compressor (P) filled with a fluid located under the middle pulley, with the piston (0) of the compressor connected to the middle pulley; f) pipes (R) connecting the compressor to a pressure vessel (Q); g) a turbine connected to the pressure vessel; and h) optionally storage tanks for storing the fluid released from the turbine, for reuse by the compressor.

Full Text

This invention relates to a power generation apparatus for generation of electric power from the energy present in waves in an ocean. There are three different forms of energy available in the waters of the ocean which can be possibly harnessed to generate power. a) Energy represented by the horizontal and vertical movement of water in "breakers" near beaches; b) Energy represented by the rise and fall of water during tides at the beaches and at the mouths of rivers and creeks; and c) Energy represented by the successive rise / fall in the level of water in waves away from beaches. Harnessing the energy contained in the waves near beaches: Considerable research work has been done thus far in the field of harnessing the energy in the waves and "breakers" laLshing the beaches. Some of the methods which have been patented are: Patents Nos. US 4,931,662; US 3,957,398; US 4,563,591; US 3,818,703; US 3,818,704; US 4,384,212; and US 3,918,260. In addition to the above methods, research has been in progress in India to tap the energy in the waves lashing the beaches by installing a heavy concrete "caisson" at the ocean-front with an opening in the caisson facing the ocean. The waves/breakers entering the opening of the caisson compress the air-mass trapped in the caisson. The compressed air is used to generate power while escaping through a turbine. Harnessing the energy contained in tidal waves: Work has also been done by researchers in various countries to exploit the energy inherent in the tidal rise and fall of water levels. For instance, at La Rance in France near the English Channel, very high variation in water level due to tides has been observed. A long wide estuary (river channel) facing the ocean fortunately exists at this location. A dam has been built at the mouth of the estuary to use the river channel as a huge reservoir for storing the incoming water of "high tide". The water is led into the reservoir through turbines, thus generating power at the time of water"s entry into the reservoir. Again, when the ocean level falls during the subsequent "low tide", the entrapped water in the reservoir is led out through the same turbines, generating power in the process. Several drawbacks were observed from the above project involving the: use of tidal energy for power generation: a) The power generation is neither continuous nor uniform during a day (of 24 hours) since it takes place only four times during the day based on the timing and level of tides; b) The "peak generation period1 does not always coincide with "high demand period1 for power; c) Locations where such high rise in water level occurs due to tides are rare in the world; d) Locations where large estuaries exist close to locations where high rise in water levels occur (due to tides) are rare ; e) The initial capital cost involved in setting up such large dam structures and installing turbines is very-high when compared with the quantum and nature of power generated. Thus the previously described methods involve setting up heavy or light permanent structures near the ocean-front for tapping the waves/breakers/tides. Since environmental groups in many countries oppose use of land near the ocean-front on the plea that the environment/ecology/aesthetics are damaged, the scope for generation of energy by these methods is somewhat limited. Further, the amount of energy tapped will be limited by the length of coast-line of the country concerned. Harnessing energy contained in waves away from shoreline: Many patents have also been obtained for exploiting the energy in the rise/fall action of the waves away from the shoreline. Some of the methods patented are : Patent Nos. EP 91303910.3 ; US 5,136,173 ; US 4,803,839 ; US 4,631,921 ; US 4,172,689 ; US 4,266,143 ; US 3,817,662 ; US 4,092,828 ; US 3,777,494 ; US 4,103,494 ; US 4,408;455 ; US 4,627,240 ; and US 4,594,853. The present invention envisages exploitation of the energy contained in the ocean waves at locations away from the coastline for power generation. The power generated by the present invention can be used for: a) Transmission to land-based consumers of power; b) "Production units" located on platforms in the ocean ; c) Power needs of ocean-going vessels. Accordingly, the present invention provides a power generation apparatus for generation of electric power from the energy present in waves in an ocean, said apparatus being located at least 10 to 30 kilometres offshore where the depth of the ocean is atleast 20 to 60 metres, and comprising : a) at least one stationary platform located atleast 4 to 8 metres above mean sea level, the length of said platform being oriented substantially parallel to predominant wavefronts at the site ; b) a plurality of floats consisting of closed cylinders suspended from longer side of said platform so that atleast 1 metre top of each float remains above the water line, said floats being spaced apart along said longer side of said platform; c) three pulleys for each said float, said pulleys being mounted on said platform with a steel wire rope passing over each outer pulley and wound once around the middle pulley; d) each said float being attached to one free end of said steel wire passing over one of the said outer pulleys and a counterweight equal to 50% of the weight W of said float being attached to the other free end of the steel wire rope passing over the other said outer pulley; e) a compressor consisting of a piston working in a cylinder located under the middle pulley, with the piston of said compressor being connected to said middle pulley, and the cylinder of said compressor being filled with a fluid; f) pipes connecting said compressor to a pressure vessel; g) a turbine connected to said pressure vessel; and h) optionally storage tanks for storing the fluid released fro the turbine, for reuse by said compressor; | such that due to rise and fall of the waves, each said float moves up and down corresponding to the rise and fall of the wave with the counterweight moving down and up in a corresponding opposite manner whereby the middle pulley, is constantly subjected to a torque of fixed magnitude in clockwise and anti-clockwise directions due to repeated rise and fall of the waves to operate the piston to compress fluid inside said compressor and generate fluid pressure to operate a turbine and generate power in a manner known per se. The platform is preferably supported on portal frames resting on the sea floor, said portal frames being braced in the longitudinal and transverse directions by means of beams. The pulleys for each compressor may be rotatably mounted on a beam so as to hang from the bottom of said beam. The middle pulley is connected to a crank-rod connected to the piston of said compressor. Preferably a plurality of said platforms are provided with each of said platform having a length of 500 to 1000 metres and width of 5 to 10 metres. Preferably the floats are spaced apart at a spacing of about 2 metres and each float is made of steel sheets of at least 12 mm thickness, 1 metre diameter and 15 to 55 metre length. Each float can be filled with concrete so that the top 1 metre length of the float remains above the surface of water. In a preferred embodiment when the deck of a ship forms the platform, the: length of the float is 10 to 15 metres and at least one streamlined enclosure surrounds said floats to prevent the trailing of the floats during movement of the ship, said enclosure being open at the top and bottom. The floats and enclosure are preferably retractably mounted. Protective coatings known per se can be provided on the platform, floats, wire ropes, compressors, pressure vessels, turbines and storage tanks, to protect them from corrosion, marine growth and the like and to ensure long maintenance-free life. Power generation on static platforms : Power is proposed to be generated by erecting suitable "power-generation platforms" in the ocean. The platforms will be made out of suitable construction materials of the known art such as steel girders/steel girders encased in cement concrete/reinforced cement concrete beams and slabs etc. The platforms would typically be about 500 to 1000 metres or more long, about 5 to 10 metres or more wide and situated about 4 to 8 metres or more above mean sea level. The length of the platform will be oriented more or less parallel to the predominant "wave-fronts" expected at the location. The platforms may be located about 10 to 30 kilometres or more from the shoreline, where the depth of ocean can be expected to range from about 20 to 60 metres or more at all times. Several floats consisting of closed cylinders, made out of about 12 mm or more thick steel sheets, of about 1 metre diameter and about 15 to 55 metre length are proposed to be hung from the platform. The steel floats will be filled with appropriate quantity of cement concrete to ensure that the top 1 metre (approx) of the floats remains above the water line. A series of such floats will be hung at about 2 metres spacing . along the length of the platform. Under the Laws of Floatation, the weight "W of each float (of 15 to 55 metre length) will be about 11 to 46 tonnes when about 1 metre length of the; float is exposed above the water-line. The exterior surface of the steel floats will be coated with suitable anti-corrosive/anti-fungal marine-grade paints to ensure long maintenance-free life. As per the invention, the successive rise and fall of each of the floats will be exploited to produce a steady-supply of power of designed capacity and frequency. Under the repeated rise and fall of the waves, the tops of floats will move up and down, more or less corresponding to the rise and fall of each wave. Three pulleys are located on the top of the platform and a steel wire rope is passed around the three pulleys. The float is hung from one of the two outer pulleys. A counterweight equal to 50% of the weight W of the float is hung from the; other outer pulley. While the rope is merely supported by the two outer pulleys, it is passed once around the middle pulley. The arrangement ensures that a constant tension equal to 50% of the weight W of the float exists in the wire-rope and also that a torque caused by the constant tension acts on the middle; pulley. Whenever the float rises through a height, of sary H,/under the effect of the crest of a wave, the counter-weight descends through a corresponding height"H.Subsequently, when the float descends through a hight, of say H1,, under the effect of the trough of the next wave, the counter-weight rises through a corresponding . heightof ."HI As such, the middle-pulley located on the platform is constantly subjected to a torque of fixed magnitude in clock-wise and anti-clockwise directions due to the repeated rise and fall of the waves. The wave-action being unending, the torque on the pulley is also continuous. As per the invention, the torque-action on the middle-pulley is exploited to operate a compressor consisting of a piston working in a or cylinder, located under the middle-pulley. The motion of the piston in the cylinder will be used to compress air or any suitable fluid. The compressed fluid generated by the series of pistons/ cylinders is piped into and stored in a pressure vessel located on the platform at a designed pressure. The fluid from the pressure vessel is used to operate a turbine to generate power at a designed voltage/frequency using equipments of the known art. After passage through the turbine, the used fluid at atmospheric pressure is led back to storage tanks for reuse by the cylinders/pistons, thus constituting a closed-circuit operation. Published literature in the field of Oceanography shows that under the action of winds blowing at about 10 kmph (light breeze) to 80 kmph (strong gale) in the open ocean, waves (swells) ranging from about 0.15 m to 5 m height are generated with their frequency ranging from about 2 to 16 seconds. Calculations show that a float of about 11 tonnes weight, with its corresponding counterweight of 5.5 tonnes, rising/falling through even 0.5 m in 4 seconds under the action of gravity can generate 6.7 kW of electricity. Corresponding calculated values of electricity that can be generated under different wind speeds, counter-weights, wave heights and frequencies are tabulated below: WIND SPEED WAVE HT. WAVE PERIOD WEIGHT OF POWER FLOAT GENERATED (KMPH) (METRE) (SECONDS) (TONNES) (KW) 15 0.5 4 11 6.7 80 5.0 16 11 16.8 15 0.5 4 42 25.7 80 5.0 16 42 64.3 Considering a platform length of 1000 metres, weight of each float as 42 tonnes, floats being located on both sides of the platform at 2 metre intervals, modest wave heights, wave frequencies of 2 to 10 seconds and losses due to friction/leakage etc as 20%, upto 20 MW of power can be generated from a single platform without incurring recurring expenditure on scarce/depleting fuel stocks as per the known art. By constructing suitable number of platforms and by using longer floats, as much power as desired can be produced from the vast ocean-surface (which is 6 times the land surface). The power generated can either be transmitted by methods of the known art to land based consumers of power or can be utilised to serve "production units" located on similar platforms nearby in the ocean,as discussed further hereafter. The advantages of producing power in this manner are numerous and are listed below in brief: a) Extent of power generation is not limited by day, night or season; b) Power generation is independent of the length of coastline of the country; c) Power produced is pollution free; d) No damage is caused to coastal ecology or aesthetics; e) There is no recurring expenditure on scarce/depleting fuels; f) No fuel need be transported for production process; g) There are no problems of waste disposal; h) Scarce land resource are not used for power production; i) Highly skilled/costly manpower is not needed for the production process, since generation and use of fluid pressure for running turbines and power generators is well known in the art of industrial engineering ; j) No heavy maintenance, repairs or replacements are involved ; and k) Existing technology is more than adequate to enable power generation without need for developing new ones. Economics of power generation by the invention : Due to the possibility of interminable generation of power by the apparatus of the present invention, several advantages become apparent as distinct from all the existing modes of power generation. The existing methods produce power just to the extent necessary to meet the demand. Problems occur in the existing methods when peak demand and peak supply mismatch. On the other hand, with the apparatus envisaged in the invention, surplus power will be available free of cost when there is low demand for power. Such surplus power can be utilized to meet the demands of several futuristic industries linked to such ocean platforms, which are unthinkable at present. While the list of such industries can be endless, some industries are mentioned below just to appreciate how the whole concept of life and civilization as existing at present can undergo a sea-change. The industries that can be envisaged are : a) Desalinisation plants for producing and supplying water to land-based communities through pipelines / tankers ; b) Salt production plants as a byproduct of desalinisation plants c) Electrolysis plants for producing and supplying Hydrogen and Oxygen through pipes/tankers for use as automotive fuel/industrial fuel for achieving zero pollution environments; d) Plants for production of Sodium, Potassium, Magnesium etc from marine salts; e) Plants for production of Chlorine and Acids; f) Plants for extracting metallic nodules from ocean-floor and processing the same; and g) Plants for processing sea-food. Even if the initial cost of production of power as per this invention is somewhat more than that by the conventional methods of power generation, it can be reduced by the methods listed above for utilizing surplus power. Further in all such costing, if system analysis is done and the total system cost taken into consideration, including savings on land-cost, cost of waste disposal/pollution/damage to aesthetics, environment etc, the method of power generation by the invention is likely to tilt the balance in its favour. Power generation for moving/static ships away from coastline: When additional power is needed for the movement of ships as well as for use by the ship"s infrastructure, it is envisaged in a preferred embodiment of the invention, that it can be generated by the same principle using floats described in the previous paragraphs. This method will be particularly useful during emergencies such as engine breakdown, ships in distress etc to augment the power-generation facilities of the known art installed on board the ships. The weight of a ship in transit being constant, the volume of water displaced by the ship is also constant as per the laws of floatation. The ship/vessel does not rest on a single wave but is supported by a group of waves with several crests and troughs. The average level of the ship"s deck with reference to average level of surrounding sea is more or less constant. However, the levels of crest and trough of individual waves differ constantly with reference to the ship"s deck-level. In the preferred embodiment of the invention, such constantly differing levels of the troughs and crests of individual waves with respect to the deck-level are exploited by means of floats. In the preferred embodiment of the invention, the length of the floats used will have to be kept about 10 to 15 metres or so (unlike 15 to 55 metres envisaged in the first embodiment) considering likely obstructions in the ship"s path. Further, generation of power can be resorted to only when the ship is in deep waters. By suitable design, the floats can be made to retract on-board when in shallow waters and during approaches to harbours etc. Another aspect needing special attention while adopting the preferred embodiment of the invention for power generation for ships is the fact that during the ship"s motion relative to water, the hanging floats will start trailing. To minimise this phenomenon, special retractable shields will have to be provided around groups of hanging floats, to reduce the tendency of floats to trail. Now the invention will described in greater detail with reference to the accompanying drawings, wherein: Fig.l shows the plan view of the "power generation platform" envisaged.. Fig.2 shows the end-view of the platform referred to in Fig.l; Fig.3 shows plan view of of the preferred embodiment of the present invention; and Fig.4 shows end-view of the preferred embodiment of Fig.3. In the embodiment shown in Figs.1 and 2, a long platform E is supported on portal frames resting on the sea floor. The portal frames A are braced in the longitudinal direction by means of beams B and C and in the transverse direction by means of beams D to withstand longitudinal and lateral forces. The longer sides of the platform are oriented substantially parallel to the predominant "wave-fronts" expected at the site of generation of power. On the shorter side of the platform E, two beams G are supported by columns F. On the underside of each beam F, three pulleys H1, J, H2 are suspended. A steel wire rope K passes over one outer pulley H1, around middle pulley J and then over the other outer pulley H2. At the free end of the wire rope K passing over the outer pulley H1, a float L is attached. At the free end of the wire rope K passing over the other outer pulley H2, a counter weight M is attached. The counter-weight is equal to half the weight of the float. The middle pulley J is connected to a crank rod N which in turn is connected to the piston rod O of compressor P. The cylinder of the compressor P is connected to a pressure vessel A and is filled with a fluid consisting of air or other suitable fluid. The floats rest in the sea water with about 1 metre at the top floating above the water level. When there is a wave, the cylinders move up and down. As a result of the rise and fall of the floats, the counter weight connected to the float by means of wire rope, moves up and down. During this motion, due to the constant tension in the wire rope K, the middle pulley J is rotated alternately in the clockwise and anticlockwise directions. During these rotations, the pulley actuates the piston of compressor P to pressure the fluid in the compressor P. These compressors have their outlets connected to a pressure vessel Q through pipes R. As a result, pressurized air / fluid is supplied to the pressure vessel Q to be stored therein. The pressure vessels are connected by means of a system of pipes known in the art to turbines known in the art so that the pressurized fluid from the pressure vessels operates the turbines to generate power. The fluid from the turbine can be released to the atmosphere. Alternatively, the fluid released from the turbine can be stored in a storage vessel (not shown). The stored fluid can then be supplied through pipes to the piston cylinders P for reuse. Before such supply for reuse the fluid from the storage vessel is preferably cleaned and filtered by means known per se. Fig. 3 shows a preferred embodiment of the present invention located on the deck of a ship. In this embodiment, the deck of the ship forms the platform of the power generation apparatus. The parts marked K, L, M, P, Q and R have the same connotation as mentioned earlier while describing the details of Fig. 1 and 2. An additional part marked S is shown in Fig. 3 which represents a streamlined enclosure for protecting the floats L from the relative motion of water while the ship is travelling. In other respects, the functioning of the components shown in Fig.3 is identical to that described for the first embodiment. In this embodiment, each of the enclosures S is shown surrounding three floats L. Fig.4 shows the preferred embodiment of the invention as located on a ship"s deck in end-view. The parts marked G, H,J, K, L, M, N, 0, P, Q, R and S have the same connotation as described in respect of Figs. 1 to 3. The stream-lined enclosure S surrounds the floats L located therein. Since sea water can enter the enclosure S from the bottom (and not from ends or sides), the level of water in the enclosure S will correspond to the level of crest/trough at the neighbourhood, while the effect of relative longitudinal movement of water is reduced considerably. Although the invention has been described with particular reference to embodiments, the invention is not limited to these embodiments, and covers all improvements or modifications falling within the scope of the invention as claimed herein. WE CLAIM : 1. A power generation apparatus for generation of electric power from the energy present in waves in an ocean, said apparatus being located atleast 10 to 30 kilometres offshore where the depth of the ocean is atleast 20 to 60 metres and comprising : a) at least one stationary platform (E) located atleast 4 to 8 metres above mean sea level, the length of said platform being oriented substantially parallel to predominant wavefronts at the site ; b) a plurality of floats (L) consisting of closed cylinders suspended from longer side of said platform so that atleast 1 metre top of each float remains above the water line, said floats being spaced apart along said longer side of said platform ; c) three pulleys (H1, J, H2) for each said float, said pulleys being mounted on said platform with a steel wire rope (K) passing over each outer pulley (H1, H2) and wound once around the middle pulley (J); d) each said float being attached to one free end of said steel wire passing over one of the said outer pulleys and a counterweight (M) equal to 50% of the weight (W) of said float being attached to the other free end of the steel wire rope passing over the other said outer pulley ; e) a compressor (P) consisting of a piston (O) moving in a cylinder located under the middle pulley, with the piston of said compressor being connected to said middle pulley, and the cylinder of said compressor being filled with a fluid ; f) pipes (R) connecting said compressor to a pressure vessel (Q); g) a turbine connected to said pressure vessel; and h) optionally storage tanks for storing the fluid released from the turbine, for reuse by said compressor; such that due to rise and fall of the waves each said float moves up and down corresponding to the rise and fall of the wave with the counterweight moving down and up in a correspondingly opposite manner whereby the middle pulley is constantly subjected to a torque of fixed magnitude in clock-wise and anticlockwise directions due to repeated rise and fall of the waves to operate the piston to compress fluid inside said compressor producing fluid pressure to operate the turbine and generate power in a manner known per se. 2. Apparatus as claimed in claim 1, wherein said platform is supported on portal frames resting on the sea floor, said portal frames being braced in the longitudinal and transverse directions with the help of beams. 3. Apparatus as claimed in claim 1 or 2, wherein said pulleys for each compressor are rotatably mounted on a beam so as to hang from the bottom of said beam. 4. Apparatus as claimed in any of claims 1 to 4, wherein said middle pulley is connected to a crank-rod connected to the piston of said compressor. 5. Apparatus as claimed in any of claims 1 to 4, wherein a plurality of said platforms are provided, with each of said platforms having a length of 500 to 1000 metres and width of 5 to 10 metres. 6. Apparatus claimed in any of claims 1 to 5, wherein said floats are spaced apart at a spacing of about 2 metres. 7. Apparatus as claimed in any of claims 1 to 6, wherein each said float is made of steel sheets of at least 12 mm thickness, 1 metre diameter and 15 to 55 metre length. 8. Apparatus as claimed in any of claims 1 to 7, wherein each float is filled with concrete so that the top 1 meter length of the float remains above the surface of water. 9. Apparatus as claimed in any of claims 1 to 8, wherein protective coatings known per se are provided on the platform, floats, wire ropes, compressors, pressure vessels, turbines and storage tanks, to protect them from corrosion, marine growth and the like. 10. Apparatus as claimed in any of the preceeding claims , wherein the deck of a ship forms said platform, the length of each said float is 10 to 15 metres and streamlined enclosure surrounds said floats to prevent the trailing of the floats during movement of the ship, said enclosure being open at the top and bottom. 11. Apparatus as claimed in claim 10, wherein said floats and enclosure are retractably mounted. 12. A power generation apparatus for generation of power from the energy present in waves in an ocean, substantially as herein described, particularly with reference to the accompanying drawings. A power generation apparatus for generation of power from the energy present in waves in an ocean, comprises : a) at least one stationary platform (E) located above mean sea level, with its length oriented substantially parallel to predominant wavefronts at the site ; b) a plurality of floats (L) suspended from longer side of that platform so that top of each float remains above the water line, the floats being spaced apart along the longer side of the platform ; c) three pulleys (H1,J, H2) for each float, the pulleys being mounted on the platform with a steel wire rope (K) passing over each outer pulley (H1, H2) and wound once around the middle pulley (J); d) each float being attached to one free end of the steel wire and a counterweight (M) of half the weight (W) of the float being attached to the other free end of the steel wire rope ; e) a compressor (P) filled with a fluid located under the middle pulley, with the piston (O) of the compressor connected to the middle pulley; f) pipes (R) connecting the compressor to a pressure vessel (Q); g) a turbine connected to the pressure vessel; and h) optionally storage tanks for storing the fluid released from the turbine, for reuse by the compressor.

Documents:

00111-cal-2002-abstract.pdf

00111-cal-2002-assignment.pdf

00111-cal-2002-claims.pdf

00111-cal-2002-correspondence.pdf

00111-cal-2002-description (complete).pdf

00111-cal-2002-drawings.pdf

00111-cal-2002-form 1.pdf

00111-cal-2002-form 18.pdf

00111-cal-2002-form 2.pdf

00111-cal-2002-form 3.pdf

00111-cal-2002-gpa.pdf

00111-cal-2002-letter patent.pdf

00111-cal-2002-others.pdf

00111-cal-2002-reply f.e.r.pdf