Abstract:
There are a large number of sites in the world&#39;s oceans and rivers that can provide a significant, viable, and cost effective source of renewable energy. Many are strategically located close to populated areas where these sites can be used to harness energy using ecologically benign hydrodynamic technology. A hydrodynamic array comprises multiple hydrodynamic elements for producing electricity by the motion of ocean tides or river currents and forces acting on the hydrodynamic array, which is immersed in ocean tides or river currents and which is in motion relative to the ocean tides or river currents.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. application Ser. No. 12/552,961, filed Sep. 2, 2009, which claims the benefit of U.S. Provisional Application No. 61/169,670, filed Apr. 15, 2009, all of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     The earth is a watery world with 71 percent of its surface covered by oceans and even its landmasses cut by rivers. The periodic rise and fall of all ocean waters is called tide, which results from gravitational attraction among the moon, sun, and earth. Although such gravitational attraction causes the vertical rise and fall of water, of particular interest to the renewable energy industry are the various horizontal or lateral movements commonly known as tidal currents or tidal streams from which great amounts of electricity can be produced. The advent of renewable energy, such as tidal energy, could be of vital importance to the future of civilization because reliance on fossil fuels cannot be sustained for another century. A transition toward renewable energy technologies would usher in a new age to supplant the age of fossil fuels, and address the problems of diminished oil reserves, destructive environmental impacts, and intractable religious conflicts. 
     SUMMARY 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     One aspect of the present subject matter includes a system for producing electricity hydrodynamically. The system comprises a viaduct through which vehicles traverse. The system further comprises a hydrodynamic array configured to support the viaduct and further configured to generate electricity from the motion of ocean tides or river currents and forces acting on the hydrodynamic array, which is immersed in the ocean tides or river currents and which is in motion relative to the ocean tides or river currents. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a cross-sectional, assembled, isometric view of an exemplary viaduct on top of an exemplary hydrodynamic array; 
         FIG. 2  is a side view of an exemplary viaduct on top of an exemplary hydrodynamic array; 
         FIG. 3  is a cross-sectional, front view of an exemplary viaduct on top of an exemplary hydrodynamic array; 
         FIG. 4  is a cross-sectional, front view of a portion of an exemplary viaduct on top of a portion of an exemplary hydrodynamic array; 
         FIG. 5  is a cross-sectional, front view of an exemplary nested machinery chamber; 
         FIG. 6  is a cross-sectional, plan view of an exemplary hydrodynamic array; 
         FIG. 7  is a cross-sectional, plan view of an exemplary hydrodynamic array; 
         FIG. 8  is a cross-sectional, side view of an exemplary upper platform/bearing assembly; 
         FIG. 9  is an isometric view of an exemplary upper fin; 
         FIG. 10  is a side view of an exemplary upper fin; 
         FIG. 11  is a plan view of an exemplary upper fin; 
         FIG. 12  is a plan view of an exemplary rotor assembly; 
         FIG. 13  is a plan view of an exemplary ring clamp and an exemplary blade support arm; 
         FIG. 14  is a cross-sectional, side view of a section of an exemplary rotor assembly; 
         FIG. 15  is a cross-sectional, side view of an exemplary center platform/bearing assembly; 
         FIG. 16  is an isometric view of an exemplary lower fin; 
         FIG. 17  is a plan view of an exemplary lower fin; 
         FIG. 18  is a side view of an exemplary lower fin; 
         FIG. 19  is a side view of an exemplary column; 
         FIG. 20  is a cross-sectional, side view of a portion of an exemplary viaduct and a portion of an exemplary portion of the hydrodynamic array; 
         FIG. 21  is a partially exploded, isometric view of exemplary base plate blocks; 
         FIG. 22  is a side view of exemplary base plate blocks; 
         FIG. 23  is a partially exploded, isometric view of a portion of exemplary columns and exemplary base plate blocks; 
         FIG. 24  is an assembled, isometric view of a portion of exemplary columns and exemplary base plate blocks; 
         FIG. 25  is a side view of an exemplary viaduct on top of an exemplary hydrodynamic array; and 
         FIG. 26  is a cross-sectional, side view of an exemplary bottom platform/bearing assembly. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments of the present subject matter are directed to a hydrodynamic array configured to produce electricity not only from ocean tides but also river currents. Suitably situated on top of the hydrodynamic array is a viaduct configured both for automobile transportation and also the construction, assembly, disassembly, installation, removal, and maintenance of pieces of the hydrodynamic array including its structural, mechanical, electrical, and electronic support equipment. Each element of the hydrodynamic array can be interconnected with another element and so on to form a porous hydrodynamic array going across a strait, passage, estuary, canal, flume, or river. 
       FIG. 1  illustrates a viaduct  100 , which comprises long elevated roadways  138   a ,  138   b  separated by a median strip  140 . The viaduct  100  consists of a series of short roadway spans interconnected with median spans, and supported by columns of a hydrodynamic array  200 . More specifically, the viaduct  100  is an array of viaduct elements. Each viaduct element is a set of members including two corresponding roadway spans (such as spans  101   a ,  101   b ). Each corresponding roadway span  101   a ,  101   b  is interconnected with a median span (such as a median span  140   a ). Each viaduct element is interconnected with other viaduct elements via latches to form a viaduct  100  (which is discussed hereinbelow). For clarity purposes the following discussion focuses on the set of roadway spans  101   a ,  101   b . Because the viaduct  100  is formed from multiple sets of roadway spans, one skilled in the art would appreciate that the discussion is pertinent to other sets of roadway spans forming the viaduct  100 . 
     The hydrodynamic array  200  is an array of hydrodynamic elements. Each hydrodynamic element is a set of members and includes four columns (such as columns  122   a ,  122   b ,  122   c , and  122   c ) supporting a viaduct element. The four columns  122   a ,  122   b ,  122   c , and  122   c  rest on four grooves  126 , which are bored into the top of a base plate block  132 . The base plate block  132  has numerous feet  134  to rest on the seafloor. Besides the four columns  122   a ,  122   b ,  122   c , and  122   c , and the base plate block  132 , the hydrodynamic element also includes a nested machinery chamber  118 ; rotor assemblies  204   a ,  204   b ; fins  308   a ,  308   b ,  312   a ,  312   b ; and platform/bearing assembly  310 ,  314 ,  2600 . In one embodiment, the hydrodynamic element includes mechanical, electrical, and electronic members to form a vertical axis hydraulic turbine for producing energy from ocean tides or river currents. Each hydrodynamic element is interconnected with other hydrodynamic element via latches to form the hydrodynamic array  200  (which is discussed hereinbelow). 
     Roadway spans  101   a ,  101   b  include guardrails  110   a ,  110   b ,  110   c , and  110   d  for warding automobiles and people away from danger as they traverse the viaduct  100 . In one embodiment, each guardrail  110   a ,  110   b ,  110   c , and  110   d  is a barrier made of suitable material, such as steel cables, placed along the edges of the roadway spans  101   a ,  101   b , and the edges of the median span  140   a . Each roadway span  101   a ,  101   b  includes a side drain  136   a, b , to allow precipitation on the roadway spans  101   a ,  101   b , to withdraw. Each roadway span  101   a ,  101   b  includes a manhole cover  102  allowing access through a manhole  106  for reaching a triangular cavity  108  for housing pipes and other conduits, such as cables, through the viaduct  100 . 
     Each roadway span  101   a ,  101   b  houses a platform on which guardrails  110   b ,  110   c  are mounted next to crane rails  112   a ,  112   b , which are manufactured of raw steel forming a track for a wheeled vehicle that carries a crane for raising, shifting, or lowering members of the hydrodynamic element by means of a hoisting apparatus supported by the crane rails  112   a ,  112   b . Adjacent to the crane rails  112   a ,  112   b  are equipment rails  114   a ,  114   b  for forming tracks for wheeled vehicles to carry various machinery. The median span  140   a  houses a machinery chamber hatch  116 , which, upon removal, allows members of the hydrodynamic element to be raised, shifted, and lowered. Near the machinery chamber hatch  116  is a manhole cover  104  allowing access to ladders that lead to various spaces of the nested machinery chamber  118 . The median span  140   a  is the top of the nested machinery chamber  118 . 
     Each column, such as columns  122   a ,  122   b ,  122   c , and  122   d , includes an upper shelf, such as upper shelves  120   a ,  120   b ,  120   c , and  120   d  (to hold upper fins  308   a ,  308   b ), and a lower shelf, such as lower shelves  124   a ,  124   b ,  124   c , and  124   d  (to hold lower fins  312   a ,  312   b ). The foot of each column is fitted into a groove  126 , which is housed by a base plate block  132 . Each base plate block rests on a sea floor via multiple feet  134 . Each base plate block is interconnected with another base plate block via latch termini  128   a ,  128   b , to link hydrodynamic elements together to eventually form the hydrodynamic array  200 . 
     In one embodiment, an arrangement of a quartet of columns  122   a ,  122   b ,  122   c , and  122   d , each thickly made from reinforced marine concrete having an elliptical or other suitable cross-sectional shape, are supported by numerous feet  134  below a base plate block mounted on the seafloor. Such an arrangement forms a foundation for stabilizing the other members of the hydrodynamic element. In one embodiment, the quartet of columns  122   a ,  122   b ,  122   c , and  122   d  guides the water flow through a vertical axis hydrofoil turbine so that additional power is obtained from the varying directions of the water flow across the turbine hydrofoils, and from one turbine duct to another. To facilitate this effect, the relationship of the turbine blades, one to the other, is synchronized. Each turbine turns in the opposite rotation direction to its neighboring turbine the latter of which is supported by another quartet of columns. This arrangement of columns eliminates or reduces interference effects between the turbine blades and the duct walls, which can cause torque fluctuations and possible fatigue of either the duct walls or the turbine blades, with eventual consequent loss of power or structural failure. 
       FIG. 2  illustrates the viaduct  100  that extends across a waterway  202  to connect land bounds  206   a ,  206   b , facilitating automobiles carrying passengers and vehicles carrying members of hydrodynamic elements to navigate across the waterway  208 . Fill dirt  202  provides support for the viaduct  100  to reach land bounds  206   a ,  206   b . As discussed previously, the viaduct  100  comprises multiple roadway spans (such as roadway spans  101   a ,  101   b ) that are interconnected with multiple median spans (such as median span  104   a ). Beneath the viaduct  100  is the hydrodynamic array  200 , of which the hydrodynamic elements are arranged among quartets of columns (such as columns  122   a ,  122   b ,  122   c , and  122   d ) supporting a pair of roadway spans and a single median span. Each hydrodynamic element of the hydrodynamic array  200  comprises one or more rotor assemblies supported by the quartet of columns that sits upon a base plate block  132  configured to receive the motion of ocean tides or river currents acting against each hydrodynamic element to generate electricity. The quartet of columns serves as structural support for the top, center, and bottom platforms  310 ,  314 , and  2600  that also house bearing assemblies, and in some embodiments, enhance the hydrofoil aspect ratio. As discussed before, the quartet of columns supports the nested machinery chamber  118 , which houses the journal and thrust bearings configured to mechanically couple to the rotor assemblies. 
     In one embodiment, the viaduct  100  crosses the waterway  208  with the hydrodynamic array  200  built from hydrodynamic elements that include single or double (stacked) rotor assemblies. In this embodiment, no onshore equipment or supporting infrastructure is needed. The porous structure of the hydrodynamic array  200  allows ocean tides or river currents to ebb after flowing. Silting is eliminated or reduced, and marine life can pass through unharmed. In this embodiment, pollution is inhibited as the submerged bearings are water lubricated. The heavy, high voltage power cables are suitably shielded against electromagnetic radiation to protect electronic equipment, vehicles, and maintenance personnel. The generators (housed by the generator chamber  544 ) are air cooled. In the same embodiment, the nested machinery chamber  118  is air conditioned to prevent equipment overheating. The nested machinery chamber  118  may also be insulated and soundproofed to avoid disturbing local inhabitants and wildlife, which includes marine life. 
       FIG. 3  illustrates the viaduct  100  being supported by columns, such as columns  122   a ,  122   b ,  122   c , and  122   d  that are members of a hydrodynamic element, one of many hydrodynamic elements comprising the hydrodynamic array  200 . As discussed previously, the viaduct  100  comprises roadway spans, such as roadway spans  101   a ,  101   b . Each roadway span  101   a ,  101   b  is in parallel to each other and comprises safety walls  316   a ,  316   b  on which guardrails  110   a ,  110   d  are mounted and beneath which side drains  136   a ,  136   b  are bored to allow withdrawal of precipitation on the roadway spans  101   a ,  101   b.    
     Each roadway span  101   a ,  101   b  houses platforms on which the guardrails  110   b ,  110   c  are mounted, the crane rails  112   a ,  112   b  are installed, and the equipment rails  114   a ,  114   b  are situated to form a track for wheeled vehicles to carry equipment to various locations along the median strip  140 . The machinery chamber hatch  116  allows access to the machinery in the nested machinery chamber  118  for maintenance and so on. The manhole cover  104  allows engineers and other personnel to access machinery in the nested machinery chamber  118 . Each roadway span  101   a ,  101   b  includes a manhole cover  102  providing access to a manhole  106  to reach triangular cavity  108  where cables, among other things, are placed. 
     Each roadway span  101   a ,  101   b  includes one or more feet  318   a ,  318   b  configured to rest transversely on top of the columns  122   a ,  122   b , and one or more tenons. Tenons  304   b ,  304   d  project from the bottom of the roadway spans  110   a ,  110   b  for insertion into mortises  304   a ,  304   c  of the columns  122   a  and  122   b . Projecting basipetally from the nested machinery chamber  118  is a torque drive shaft  306  that is coupled to an upper rotor assembly  204   a  and a lower rotor assembly  204   b . The torque drive shaft  306  is also coaxially aligned with an upper platform/bearing assembly  310  and a center platform/bearing assembly  314 . Holding the upper platform/bearing assembly  310  rigidly into place among the quartet of columns are upper fins  308   a ,  308   b . Similarly, lower fins  312   a ,  312   b  rigidly maintain the center platform/bearing assembly  314  in place among the quartet of columns, which are placed on top of the base plate block  132 , which itself rests on multiple feet  134  on the sea floor  130 . 
     In one embodiment, the width of each member of the quartet of columns  122   a ,  122   b ,  122   c , and  122   d , as well as the height from the feet  134  to the nested machinery chamber  118 , help to eliminate or reduce water flow blockage. The height of the quartet of columns  122   a ,  122   b ,  122   c , and  122   d  also keeps the nested machinery chamber  118  above unusual wave heights, driven by violent weather patterns. Such an arrangement isolates the nested machinery chamber  118 , and inhibits or reduces capsizing forces due to unusual wave heights. Also in this embodiment, the floor of the nested machinery chamber  118  provides in essence an upper end plate effect for the rotor assemblies a few meters below low tide level to prevent cavitation of the hydrofoils. In one embodiment, the base plate block  132 , whose grooves form an egg-crate like structure, with feet  134  forming a web structure, are configured to further stabilize the hydrodynamic element. The web structure also prevents or reduces seawater from flowing under the base plate block. 
     To facilitate raising, shifting, and lowering members of the hydrodynamic element, each of the bearing support structures (such as the upper platform/bearing assembly  310 , the center platform/bearing assembly  314 , and the lower platform/bearing assembly  2600 ) is engineered to have a configuration that incorporates a portion of the bearings through which the torque drive shaft is positioned. The orifices defined by these bearing support structures are larger than the torque drive shaft diameter. In addition, a bearing support structure that is lower than a bearing support structure above is suitably smaller than the one above it to allow raising, shifting, and lowering into place. 
     The nested machinery chamber  118 , as a member of the hydrodynamic element, is suitably manufactured from reinforced concrete elements. The nested machinery chamber  118  may be raised, shifted, or lowered through the machinery chamber hatch  116  using a suitable crane moved into position using the crane rails  112   a ,  112   b . Suitably, the generator chamber housed by an upper machinery chamber  514  is removed first in a process of disassembling members of the hydrodynamic element. Next, the crane removes an upper machinery chamber  514 , followed by pieces of equipment housed by the lower machinery chamber  516 , the lower machinery chamber  516  itself, and the assemblies connected with the torque drive shaft  306 , such as the upper platform/bearing assembly  310 , the upper rotor assembly  204   a , the center platform/bearing assembly  314 , the lower rotor assembly  204   b , and the lower platform/bearing assembly  2600 . Each assembly is disassembled in turn as each is withdrawn and is subsequently moved by the crane to an equipment vehicle positioned on the equipment rails  114   a ,  114   b  for transportation. As would be appreciated by one skilled in the art, the process of assembling members of the hydrodynamic element occurs in a time reversal fashion to the sequence of events discussed above. 
       FIG. 4  illustrates an interconnection between a roadway span (such as the roadway span  101   a ) and a column (such as the column  122   a ) in greater detail. As previously discussed, the roadway span  101   a  includes guardrails  110   a ,  110   b  to prevent an automobile from trespassing beyond the safety wall  316   a  or veering into the median span  140 . On the roadway  138   a  is a manhole cover  102  allowing access to the manhole  106  to reach the triangular cavity  108 , which is configured to carry power and communication cables, fresh water mains, and other non-flammable and non-explosive substances. The side drain  136  allows precipitation on the roadway  138  to withdraw. The median span  140  also includes crane rails  112   a  as well as equipment rail  114   a.    
     A latitudinal latch terminus  402  allows the roadway span  101   a  to mate and engage the median span  140   a  so as to fasten to the median span  140   a . More specifically, the latitudinal latch terminus  402  of the roadway span  101   a  mates with the latitudinal match terminus  508   a  of the nested machinery chamber  118  (the top of which is the median span  140   a ). The foot  318   a  protruding from the roadway span  101   a  sits transversely on top of the column  122   a . Further, projected from the bottom of the roadway span  101   a  is the tenon  304   b  that mates with the U-shaped mortise  304   a  on top of the column  122   a . A ledge  406  is joined to the top of the column  122   a  via a rectangular mortise  404 , which mates with the bottom of the nested machinery chamber  118  to securely support it. 
       FIG. 5  illustrates the nested machinery chamber  118 . At its apex, the nested machinery chambers  118  are covered by a machinery chamber hatch  116 , which upon opening, allows access to the equipment inside. The sides of the nested machinery chamber  118  conclude with latitudinal latch termini  508   a ,  508   b , which mate with corresponding latitudinal latch termini, such as the latitudinal latch terminus  402  of the roadway span  101   a , to structurally fasten the nested machinery chamber  118  into an opening defined by a quartet of columns, such as columns  122   a ,  122   b ,  122   c , and  122   d , underneath a pair of roadway spans  101   a ,  101   b . A set of manhole covers  104   a ,  104   b ,  104   c  provide access to upper ladder  506   a , middle ladder  506   b , and lower ladder  506   c , each in turn allowing personnel to access the nested machinery chamber  118 . Near the lower manhole cover  104   c  is a hatchway  512  giving access to one or more interconnected, nested machinery chambers  118 . A set of fireproof steel doors  510 ,  510   b ,  510   c  more specifically allow personnel to access and maintain pieces of equipment connected with a hydrodynamic element. 
     The nested machinery chambers  118  include an upper machinery chamber  514  and a lower machinery chamber  516 . The lower machinery chamber  516  has contoured reinforced ledges which mate with ledges on the upper machinery chamber  514  to secure the two chambers together. The upper machinery chamber  514  is accessible via the manhole cover  104   a  and the ladder  506   a . The upper machinery chamber  514  houses a generator chamber  544 . With the opening of the machinery chamber hatch  116 , the generator chamber  544  can be placed inside the upper machinery chamber  514  via eye bolts  538   a ,  538   b , which are used to hoist the generator chamber  544  slowly into the inside of the upper machinery chamber  514 . The top of the generator chamber  544  is lidded by a safety cover  546 . Mounted on top of the safety cover  546  is an exciter  548 , which is either a generator or a battery that supplies electric current used to produce a magnetic field in a synchronous generator  502 . The generator  502  converts mechanical energy received from a thrust bearing  504  to electrical energy. 
     The thrust bearing  504  is mechanically coupled to a gear box  540  via high-speed gear coupling  542 . The gear box  540  is used here for illustrative purposes in one embodiment. However, any suitable gearing or transmission may be used, such as a direct drive permanent magnet variable speed generator. Eye bolts  538   c ,  538   d  allow the gear box  540  to be hoisted to its position within the lower machinery chamber  516 . Lugs  518   a ,  518   b  allow a portion of the lower machinery chamber  516  to be hoisted into place inside the nested machinery chambers  518 . Coupled to the gear box  540 , which allows variable speed, is an epicyclic train  536  which comprises a series of moving mechanical parts that transmit and modify mechanical energy communicated by the gear box  540  to the thrust bearing  504 . Eye bolts  538   e ,  538   f  allow the epicyclic train  536  to be lowered into the lower machinery chamber  516 . The epicyclic train  536  is mechanically coupled to a torque shaft head  524  via a low-speed gear coupling  534 . A disk brake  532  regulates the velocity of the torque shaft head  524  by providing friction from a caliper pressing against the sides of the torque shaft head  524 . A neck  528  coaxially locates the torque shaft head via spherical roller thrust bearing  530   a ,  530   b . Oil is provided to lubricate the spherical roller thrust bearing  530   a ,  530   b . Oil seals  522   a ,  522   b  prevent leakage of the oil into a torque shaft cover  526 , hence protecting the torque shaft  306 . The neck  528  is fastened to the lower machinery chamber  516  via bolts  520   a ,  520   b . The remaining portion of the lower machinery chamber  516  is hoisted into place via lugs  518   c ,  518   d.    
     In one embodiment, the nested machinery chamber  118  is fabricated using a suitable material. One suitable material includes reinforced marine concrete. Another suitable material includes a corrosion-resistant metal. The generator chamber  544  is fabricated using a suitable material. One suitable material includes heavily reinforced concrete. The generator chamber  544  with upper and lower support ledges is nested securely in the upper machinery chamber  514 . The generator chamber  544  suitably is formed as a cylindrical structure, which functions as a containment vessel in the event that the generator  502  should fail, such as from a structural failure or from being sped errantly to cause disintegration. The top of the generator chamber  544  protects the generator  502  from debris or tools and so on. 
     For oil-lubricated spherical roller thrust bearings  530   a ,  530   b , the oil is supplied from an adjacent pressurized lubrication tank (not shown), which has provisions for cooling, circulating, and pumping out the oil prior to removing the torque shaft spline drive. The lubrication system also provides oil to the torque shaft at the junction of the upper rotor assembly and the lower rotor assembly. The lubrication system is integrated with other systems for pumping, cooling, conditioning, and detecting contaminants, as well as salt water removal, overheating and level alarms. 
       FIG. 6  is a cross-sectional view of the hydrodynamic array  200  taken below the upper platform/bearing assembly  310 . Two members of the quartet of columns are in parallel to the other two remaining members of the quartet of columns. For example, columns  122   a ,  122   b  are in parallel position with respect to columns  122   c ,  122   d . Cross sections of the four columns,  122   a ,  122   b ,  122   c , and  122   d , are illustrated. A set of lower fins  312   a ,  312   b  rests on the shelves of the columns  122   a ,  122   b ,  122   c , and  122   d . More specifically, the lower fin  312   a  is secured between columns  122   a ,  122   c . The lower fin  312   b  is secured between columns  122   b ,  122   d . Also illustrated is a rotor assembly  204   a . Suitably, other rotor assemblies adjacent to the rotor assembly  204   a  turn in an opposing direction from the direction of the rotor assembly  204   a.    
       FIG. 7  is a cross-sectional view of the hydrodynamic array  200  taken below the center platform/bearing assembly  314 . Two members of the quartet of columns are in parallel to the other two remaining members of the quartet of columns. For example, columns  122   a ,  122   b  are in parallel position with respect to columns  122   c ,  122   d . Cross sections of the four columns,  122   a ,  122   b ,  122   c , and  122   d , are illustrated. Grooves  126   a ,  126   b ,  126   c , and  126   d  house the feet of the columns  122   a ,  122   b ,  122   c , and  122   d . Also illustrated are T-shaped latch members  702 . The lower rotor assembly  204   b  is shown 45 degrees out of phase with the adjacent rotor assemblies on top of the T-shaped latch members  702  to illustrate the opposing direction that the lower rotor assembly  204   b  turns with respect to its adjacent neighboring lower rotor assemblies. 
       FIG. 8  illustrates a cross-sectional, side view of the upper platform/bearing assembly  310 . A torque shaft  306  is coaxially aligned with the upper platform/bearing assembly  310 . A torque shaft cover  802  includes lifting lugs that allow the upper platform/bearing assembly  310  to be raised, shifted, or lowered into position against the ledges of the upper fins  308   a ,  308   b . Surrounding the torque shaft  306  is a bearing cylinder  806 , which is axially aligned with stave bearing elements  804 . The bearing cylinder  806  is mechanically coupled to a shaft segment  808  via a C-shaped clamp  810 . 
     In one embodiment, the bearing assembly portion of the upper platform/bearing assembly  310  is formed from a thick-walled cylinder with disc and ribs that are embedded in the upper platform/bearing assembly  310 . The interiors of the cylinders are machined to support stave bearing elements  804 , suitably made from heavy-duty composite water-lubricated structures. Suitably, the stave bearing elements are kept from overheating although they can function under extreme abuse, such as with high fluctuating loads, grit and other contaminants, misalignment and water flow blockage. It is suitable to circulate seawater through the stave bearing elements  804  to reduce overheating. Water circulation is facilitated by the upper and lower rotor assemblies  204   a ,  204   b  as they draw seawater up between the stave bearing elements  804  and expel the seawater through the exhaust holes (not shown) in the torque shaft cover  802 . Since warm seawater tends to rise from heating of the stave bearing elements  804 , this assists in the circulation of the seawater through the spaces among the stave bearing elements  804 . 
       FIGS. 9 ,  10 , and  11  illustrate an exemplary upper fin, whose implementation includes the pair of upper fins  308   a ,  308   b , which are secured to the shelves  120   a ,  120   b ,  120   c , and  120   d  of quartet of columns  122   a ,  122   b ,  122   c , and  122   d . The upper fin  308   a  includes a distal end  1008  and a proximal end  1010 . At the proximal end  1010 , a knob  1004  protrudes and forms a ledge  1006  at the terminus of the upper fin  308   a . A number of holes  1002  accommodate bolts that secure the upper fin onto the shelves  120   a ,  120   b ,  120   c , and  120   d  of the columns  122   a ,  122   b ,  122   c , and  122   d.    
     In one embodiment, the upper fins are used in pairs. The pair of upper fins helps to eliminate or reduce cavitation and wave diversion. Suitably, each upper fin is formed from reinforced concrete. Each upper fin is attached to each side of two members of the quartet of columns by bolts, suitably at a corrosion-resistant angle. The pair of upper fins (such as the pair of upper fins  308   a ,  308   b ) maintains separation of the quartet of columns and stabilizes its alignment as well as supports the upper platform/bearing assembly  310 . The pair of upper fins has upward curving distal ends  1008  to guide the flow of ocean tides or river current under the upper fins to a depth that eliminates or reduces cavitation while providing ventilation of the upper/lower rotor assemblies. The height of the distal end  1008  is such that normal ocean tides and river currents are directed through the upper/lower rotor assemblies, while waves driven by violent weather patterns pass above the upper fins (in combination with the upper platform/bearing assembly  310 ) and the bottom of the nested machinery chamber  118 . 
       FIGS. 12 and 13  illustrate a plan view of a stage of a rotor assembly, such as the upper rotor assembly  204   a  or the lower rotor assembly  204   b . A stage of the rotor assembly comprises four blades,  1420   a ,  1420   b ,  1420   c , and  1420   d  that are coupled to a ring clamp  1202  via blade support arms  1408   a ,  1408   b ,  1408   c , and  1408   d . Each rotor assembly comprises multiple stages interconnected with each other through one or more shaft segments. Suitably a rotor assembly has four stages, but any number of stages is possible. The rotor assembly (upper/lower rotor assemblies  204   a ,  204   b ) is an active element in the hydrodynamic element, capturing ocean tidal energy or river current energy by the blades  1420   a ,  1420   b ,  1420   c , and  1420   d . The blades (or foils)  1420   a ,  1420   b ,  1420   c , and  1420   d  produce significant lift. The mechanical energy in the lift is communicated to the drive shaft as torque through the blade support arms. And this mechanical energy is further communicated and relayed by various members of the hydrodynamic element to drive the generator  502  through the gearbox  540 . 
       FIG. 14  illustrates a portion of the rotor assembly, such as the upper rotor assembly  204   a , in greater detail. Shaft segments  1402 ,  1404  are coupled together via a C-shaped terminus  1406  of a blade support arm  1408 . The C-shaped terminus  1406  is fastened via one or more bolts  1416  piercing through the pre-bored holes in the ring clamp  1202 . One or more alignment bolts  1412  situate the shaft segment  1402  with the shaft segment  1404 . One or more seals  1410  provide a tight closure to inhibit fluids from entering the shaft segments  1402 ,  1404 . At the distal end of the blade support arm  1408 , one or more blades  1420  are coupled via one or more bolts  1418 . 
       FIG. 15  illustrates a cross-sectional view of the center platform/bearing assembly  314  in greater detail. The torque shaft  306  coaxially locates with respect to the center platform/bearing assembly  314 . A rotor lift cover  1502  includes lugs for allowing the center platform/bearing assembly  314  to be raised, shifted, or lowered, and mates with the ledge termini of a pair of lower fins  312   a ,  312   b . A bearing cylinder  1506  is coupled to a shaft segment  1510  via a C-shaped clamp  1508 . The bearing cylinder  1506  engages with stave bearing elements  1504 . The center platform/bearing assembly  314  is suitably formed from a circular shape, which is configured to allow the center platform/bearing assembly  314  to pass through the opening provided by the pair of upper fins  308   a ,  308   b . The center platform/bearing assembly  314  has tapered ledge termini to mate with the lower fins  312   a ,  312   b , so as to allow the lower fins  312   a ,  312   b  to carry the weight of the center platform/bearing assembly  314  and the lower rotor assembly  204   b.    
     In one embodiment, the bearing assembly portion of the center platform/bearing assembly  314  is formed from a thick-walled cylinder with disc and ribs that are embedded in the center platform/bearing assembly  314 . The interiors of the cylinders are machined to support stave bearing elements  1504 , suitably made from heavy-duty composite water-lubricated structures. Suitably, the stave bearing elements are kept from overheating although they can function under extreme abuse, such as with high fluctuating loads, grit and other contaminants, misalignment, and water flow blockage. It is suitable to circulate seawater through the stave bearing elements  1504  to reduce overheating. Water circulation is facilitated by the upper and lower rotor assemblies  204   a ,  204   b  as they draw seawater up between the stave bearing elements  1504  and expel the seawater through the exhaust holes (not shown) in the torque shaft cover  1502 . Since warm seawater tends to rise from heating of the stave bearing elements  1504 , this assists in the circulation of the seawater through the spaces among the stave bearing elements  1504 . 
       FIGS. 16-18  illustrate the lower fins, such as the lower fins  312   a ,  312   b , in greater detail. The lower fin includes a distal end  1704  and a proximal end  1702  that terminate in an arc and bifurcated to form a ledge terminus  1706 . A number of holes  1708  accommodate bolts to fasten the lower fin to the lower shelves  124   a ,  124   b ,  124   c , and  124   d , of the columns  122   a ,  122   b ,  122   c , and  122   d.    
     In one embodiment, the lower fins are used in pairs. The pair of lower fins helps to eliminate or reduce cavitation and wave diversion. Suitably, each lower fin is formed from reinforced concrete. Each lower fin is attached to each side of two members of the quartet of columns by bolts, suitably at a corrosion-resistant angle. The pair of lower fins (such as the pair of lower fins  312   a ,  312   b ) maintains separation of the quartet of columns and stabilizes its alignment as well as supports the lower platform/bearing assembly  314 . The pair of lower fins has a horizontal orientation to function as end plates for the rotor assemblies and guide the flow of ocean tides or river current toward the rotor assemblies. 
       FIG. 19  illustrates a side view of a column, such as the column  122   a . The top of the column  122   a  includes an U-shaped mortise  304   b  that mates with a tenon  304   a  protruding from a roadway span, such as the roadway span  101   a . The column  122   a  includes a ledge  406 , which is interposed by a rectangular mortise  404 . The ledge  406  together with the rectangular mortise  404  of the column  122   a , as well as three remaining members of the quartet of columns mounted on a base plate block, supports a nested machinery chamber  118 . A shelf  120   a  allows an upper fin to be secured to support the upper platform/bearing assembly  310 . Another shelf  124   a  provides support for the lower fins  312   a ,  312   b . The column  122   a  includes a foot  1902  that fits in a groove on the base plate block. 
     Suitably the foot  1902  is grouped and bolted into a groove on the base plate block. As previously illustrated, the cross section of the columns reveals a streamlined shape depicted illustratively as an ellipse, but any suitable cross-sectional shapes can be used. One suitable cross-sectional shape includes a symmetric airfoil with trailing edge toward the center. Another suitable cross-sectional shape includes a rectangle with rounded ends. The upper portion of the column  122   a  is configured to support and latch in place the nested machinery chamber  118  and a roadway span. The cross section of the column  122   a  as illustrated previously reveals, in one embodiment, heavy wall construction of reinforced concrete and integral spars creating three spaces which can be filled with aggregate or sand. 
       FIG. 20  illustrates a cross-sectional, side view of a portion of the viaduct  100  and the columns. More specifically, the portion of the viaduct  100  illustrated here includes the roadway span  101   a , on top of which is a guardrail  110   a . The roadway span  101   a  is interconnected with other roadway spans by mating mechanical members, such as a longitudinal male latch terminus  2002   a  or a void that defines a longitudinal female latch terminus  2002   b , all configured to engage to fasten to each other. The roadway span  101   a  is further configured to include feet  2204   a ,  2204   b  which rest on top of the columns  122   a ,  122   c.    
       FIGS. 21 ,  22  illustrate base plate blocks  132  and their interrelationship in greater detail. Each base plate block  132  includes a number of feet  134  that rest on the seafloor. An I-shaped beam  130  provides further support to the base plate blocks  132  with the seafloor. The top of each base plate block  132  includes four grooves  126 , each groove  126  housing a foot of a column, such as columns  122   a ,  122   b ,  122   c , and  122   d . At the center of the base plate block  132  is a bore  2104  that accommodates a bottom platform/bearing assembly  2600 . On either side of the base plate block  132  are latch termini  128  configured to abut with the latch termini of adjacent base plate blocks  132 . A T-shaped latch member  702  engages the latch termini  128  of adjacent base plate blocks  132  to mate and bring adjacent blocks  132  into mutual fastening. On top, at the center of the T-shaped latch member is a bore  2102  that preferably shares similar dimensions of the bore  2104  to accommodate the bottom platform/bearing assembly  2600 . 
     The columns and the base plate blocks of various embodiments of the present subject matter provide permutations to support a stable installation of seabed support structures depending on the type of bottom composition, depth of the water, size of the largest waves of the locality, type of supported local construction, seismic activity, rotor drag for the hydrodynamic array, and topside loading if road or rail traffic is involved. In one embodiment, a base plate block supports a quartet of columns whose center houses the upper platform/bearing assembly, the center platform/bearing assembly, and the bottom platform/bearing assembly. 
       FIG. 23  illustrates a partially exploded, isometric view of the interrelationship between the columns and the base plate blocks  132 . Each base plate block  132  is mutually fastened to an adjacent base plate block  132  via one or more T-shaped latch members  702 . Each base plate block  132  includes four grooves  126 , each groove housing a foot of a column.  FIG. 24  illustrates an assembled, isometric view of the interrelationship between the columns  122  and the base plate blocks  132 . 
       FIG. 25  illustrates a side view of the viaduct and its interrelationship with the hydrodynamic array. The viaduct  100  is shown to include multiple roadway spans  101  that are interconnected with one another while resting on top of columns  122 . Between each column  122 , from a side view, are the nested machinery chambers  118 . Protruding below each nested machinery chamber  118  is the torque drive shaft  306  that is partially hidden by the upper fins  308 . Below the upper fins  308  are one or more upper rotor assemblies  204   a . Interposed between the upper rotor assemblies  204   a  and the lower rotor assemblies  204   b  are one or more lower fins  312 . The lower rotor assemblies  204   b  and the columns  122  rest upon one or more base plate blocks  132 . 
       FIG. 26  illustrates a cross-sectional, side view of the bottom platform/bearing assemblies  2600 . A shaft segment  2602  is coupled to a bearing cylinder  2606  via a C-shaped clamp  2604 . The bearing cylinder  2606  is retained to the bottom platform/bearing assemblies  2600  by a cover plate  2610  that holds down the bearing cylinder  2606 . The bearing cylinder  2606  engages the bottom platform/bearing assemblies by stave bearings  2608 . 
     In one embodiment, the bearing assembly portion of the lower platform/bearing assembly  2600  is formed from a thick-walled cylinder with disc and ribs that are embedded in the lower platform/bearing assembly  2600 . The interiors of the cylinders are machined to support stave bearing elements  2608 , suitably made from heavy-duty composite water-lubricated structures. Suitably, the stave bearing elements are kept from overheating although they can function under extreme abuse, such as from high fluctuating loads, grit and other contaminants, misalignment, and water flow blockage. It is suitable to circulate seawater through the stave bearing elements  2608  to reduce overheating. 
     While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.