General

        Wave energy is considered as one of the most promising alternate energy source due to high concentration factor, and to high availability factor (day & night), compared to wind and solar energy. 

        Waves have energy ranging from 1.1 to 188 KW for 0.5 to 8 meters height respectively.

Existing systems: 

        The idea of converting sea wave energy into electric energy had been investigated by many that proposed different devices.  However, these devices are limited in the amount of power they produce, have low efficiency, require expensive structures, destroy coral reef and are unable to produce power in sizeable quantities.

        Current devices are listed at websites  http://peswiki.com/energy/Directory:Ocean_Wave_Energy ,

Proposed Systems

Three systems are proposed as summarized below and detailed under respective product at www.renewableenergypumps.com:

 

      I.  Wave Gear Drive –WGD

     II.  Wave Water Pumps – WWP

    III.   Wave Air Pumps - WAP

a.   All systems are based on basic hydraulic engineering principles.

b.   Compressed Air Injection Systems and fogging (injecting water vapor into turbine air inlet) are known and proven technologies.

c.   Variable Speed Generators: Variable input RPM with constant voltage and frequency output suitable for parallel operation.  Transformers step up the VSG output for power transmission to the shore line.

d.   All systems are suitable for onshore or offshore installation.

e.   All systems consist of independent construction units having seventy (10x7) pumps or generators with an output of 507 KW at four (4) meter high waves and a foot print of 21x15 meters at the sea bed.

f.    All systems can extract energy from waves in the range of 75 to 800 centimeters range. Other ranges are available and depend upon the sea state.

g.   All systems provide a Free Floating Break Water Structure to protect and preserve the shoreline.

I. Wave Gear Drive -WGD

1.   The WGD System converts sea wave energy to mechanical drive using wave undulations and a buoyant float directly acting on a spiral spring or rack and pinion and Variable Speed Gear to drive:

a.  A rotary, constant RPM water pump that pumps a small quantity of water to a high head, collect it and feed it to a hydro turbo generator. or

b.  A Variable Speed Input/Constant Speed Output (VSG) generator.  The generators can be either alternating or direct current depending upon Client requirements and are run in parallel.

2.   Pumps or Generators are installed:

a.  5-meters below Mean Sea Level on a floating structure with quick coupling and decoupling means for ease of installation and maintenance, or

b.  On a fixed offshore structure whose deck is 6-mmeters above sea water level

                            i.  In this case a pulley is fixed to the underwater structure anchors to convert the uplift of the main float to a downward pull acting on the rotary pumps or VSG resting above water on the decking of the fixed structure.

                           ii.  All installation, operation and maintenance work are done above water at the structure decking.

3.   Construction units comprise seventy (70) pumps or generators consisting of ten (10) sets, each set with seven pumps or generators. The footprint for the installation unit measures 21x15 meters, the structure deck measures 16x25 meters.

4.   Up to forty construction units can be installed in an area one kilometer wide (40x70 pumps or generators) capable of generating 20 megawatts from a four meter high wave.

 5.  Ideal for use on offshore oil rigs to generate electric power or using water pumps to pump deep cold water and use the water temperature difference  between  surface and bottom for air conditioning (SWAC), or to generate additional electric power.

 6.  Should be a requirement to be installed on inhabited off shore oil platforms for air conditioning and electric power generation.

 II. Wave Water Pumps - WWP

1.   The WWP converts sea wave energy to mechanical drive using wave undulations and a buoyant float directly acting on a positive displacement reciprocating pump to pump a small quantity of water to a high head, collect it in a piping network and feed it to a hydro-turbo generator.

2.   Pumps are installed on a floating underwater structure at six (6) meters below mean sea level, with quick coupling and decoupling means for ease of installation and maintenance.  The hydro turbo generator is installed at a fixed structure and anchored to the sea bed.

3.   Construction units comprise seventy pumps consisting of ten sets, each set with seven pumps. The footprint for the installation unit measures 21x15 meters, the structure deck measures 16x25 meters.

4.   Up to forty construction units can be installed in an area one kilometer wide (40x70 pumps) and capable of generating 20 megawatts from a four meter high wave.

 

III. Wave Air Pumps - WAP

1.   The WAP utilize the kinetic energy of the sea wave to compresses a small quantity of air to a high pressure, collect it in a piping network and feed it into the air inlet of a turbo generator.

2.   Another turbine is installed to capture the energy from the air as it rushed into the pump on the downward motion of the wave.  This energy can be used to drive auxiliaries and/or to add to the output of the plant.

3.   Fuel is injected as needed to maintain turbo generator output irrespective of availability of waves, thus producing dependable electric power.

4.   Pumps are installed on a floating underwater structure at six (6) meters below mean sea level, with quick coupling and decoupling means for ease of installation and maintenance.  The hydro turbo generator is installed at a fixed structure and anchored to the sea bed.

5.   Compressed air technology and fogging (adding water vapor to turbine air inlet) are known and proven technologies. The system generates energy at normal fuel rate in the absence of waves, and at reduced fuel consumption inversely proportional to wave heights.

6.   Construction units comprise seventy pumps consisting of ten sets, each set with seven (7) pumps. The footprint for the installation unit measures 21x15 meters.

7.   Up to forty (40) construction units can be installed in an area one kilometer wide (40x70) pumps capable of generating 20 megawatts from a four meter high wave.

8.   Ideal for off-shore wind turbine farms, as it utilizes the off-shore wind turbine supporting structure as a Wave Air Pump at negligible cost.

9.   The WAP is ideal for sea water aeration by injecting compressed air into the sea to enhance the oxidation process of organic materials.

 

WAP – Calculation and Drawings  Available upon request

Table -2 (Partial View) shows for ten (10) sets of seven pumps output for waves ranging from 1.5 to 6.0 meters

             for a Main Float diameter of 150 centimeters.

 

Table -5   Average Wave Height Hourly/Year Sea State Distribution

                    and Generated KWH per Year

 

Table -2 shows for a set of seven pumps output for waves ranging from 1.5 to 6.0 meters

 for a Main Float diameter of 150 centimeters. Performance for 220 cm O.D. Float is available