POWER GENERATING SYSTEM

POWER GENERATING SYSTEM

THIS INVENTION relates to the generation of power. In particular, the invention relates to a method for generating power through utilization of water flow. The invention also extends to a power generating apparatus or system used in such method.

BACKGROUND TO THE INVENTION

Multiple types of power generating systems, especially in the field of green energy, are known and used nowadays. Accordingly, the field of hydro energy generation through use of a renewable energy resource such as water has received a lot of attention in the recent past.

The broad concept of being able to generate power using a hydro turbine power generation system incorporating both machines or engines for liquids and a dynamo-electric machine is not new. Autonomous hydro turbine generators is for example described in published PCT international application number WO20101 39074 (A1 ) whereas a self-generated flow engine is disclosed in Mexican patent application number MX2009003665 (A). Self-powered hydro-electric power generators are disclosed in United States patent application number US20031 67760 (A1 ) and self-sustaining water flow circulation type hydraulic power generation equipment in Japanese Patent application number JP20081 57124 (A). Furthermore, a self-pumping apparatus is described in Australian patent application number AU2006201539 (A1 ) while turbines which become self-powered after production starts is described in WO2012014232 (A2). However, the applicant believes that these power generating systems do not sufficiently exploit water flow in generating power and it is therefore an object of this invention to provide an improved method for generating power using flow of water and a power generating apparatus for use in such method.

SUMMARY OF THE INVENTION

According to the invention there is provided a power generating system or apparatus comprising: a water supply reservoir linked via a water feed flow path to a water return reservoir, which in turn is back linked to the water supply reservoir by way of a water return flow path ; a hydro turbine having a prime mover and being operatively positioned in the water feed flow path to use water supplied from the water supply reservoir to turn the prime mover such that used water is transferred to the water return reservoir and available for return to the water supply reservoir via the water return flow path; at least one pump in fluid communication with the water supply reservoir and the hydro turbine via the water feed flow path, the at least one pump being configured to pump water at a constant flow rate from the water supply reservoir; and wherein the water supply reservoir and the hydro turbine are substantially level relative to each other and the water feed flow path includes dynamic pressure increase means proximate the prime mover such that the power generated by the hydro turbine increases as the dynamic pressure of the water increases.

The invention also provides for the dynamic pressure increase means to comprise a gradually decreasing diameter portion provided in the water feed flow path proximate or adjacent the prime mover.

Alternatively, the invention provides for the dynamic pressure increase means to comprise a plurality of dynamic pressure increase pumps which are provided in series relative to one another in the water feed flow path. Further alternatively, the invention provides for the dynamic pressure increase means to comprise a dynamic pressure increase valve having a valve member which is movably positioned to permit back and forth movement of the valve member within the water feed flow path proximate the prime mover.

Preferably, the valve comprises a stem having a valve member with a pear-shaped head and a pointed toe such that movement of the valve member towards the prime mover defines two ports which gradually decrease in size, whereas movement of the valve member away from the prime mover defines two ports which gradually increase in size.

The invention further provides for the at least one pump to include switching means to permit a power source switch over. Preferably, the at least one pump is diesel or petrol driven and configured to be switched over when desired to receive power from the power generating system hereinbefore described. In an embodiment of the invention, a plurality of pumps with check valves are provided in parallel to handle planned water flow via the water feed flow path. In an example embodiment, the water supply reservoir is a lake, river, ocean, natural dam or man-made dam.

According to a further aspect of the invention there is provided a method for generating power through utilization of water flow, the method comprising: positioning at least one pump in a water feed flow path and in fluid communication between a water supply reservoir and a prime mover of the system as hereinbefore described, which water supply reservoir and prime mover lie in substantially the same plane; ensuring that a dynamic pressure increase means is located in the water feed flow path adjacent or proximate the prime mover; powering the at least one pump by means of an external power source thereby to effect pumping of water through the water feed flow path via the dynamic pressure increase means and prime mover into a water return reservoir; and actuating the switching means to switch over from external power supply to power provided by the hydro turbine of the power generating system hereinbefore described.

The method may also include distribution to the grid of excess generated by the power generating system hereinbefore described. Alternatively, the method includes use of any excess power generated by the power generating system hereinbefore described to drive one or more pumps of one or more similar power generating systems arranged in series to generate an increased amount of power.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention is now described, by way of example, with reference to the accompanying non-limiting diagrammatic drawings. In the drawings:

Figure 1 shows a plan view of a power generating system according to an embodiment of the invention; and Figure 2 shows an exploded section view of a valve of the power generating system of Figure 1 , shown in an open and partially closed position respectively.

DETAILED DESCRIPTION OF THE DRAWINGS

This description is presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how at least one form of the invention may be embodied in practice. Turning now to Figure 1 , a power generating system or apparatus, in accordance with the invention is illustrated. The power generating system is generally indicated by means of reference numeral 10. System 10 is particularly adapted to utilize water flow to generate power or electricity.

System 10, as shown in Figure 1 , includes a water supply reservoir in the form of a primary pool 12 and a water return reservoir in the form of a secondary pool 14. Water is transferrable between the pools 12, 14 via a water feed flow path or piping system 16 and a water return flow path 18.

System 10 is further provided with a hydro turbine 20 having a prime mover (not shown) which rotates as a result of water flow. The hydro turbine is located at the end of the water feed flow path and water discharged from the turbine after having effected movement of the prime mover flows into the secondary pool 14 from where it is re-channelable to the primary pool 12. The hydro turbine 20 is thus operatively positioned in the water feed flow path 16 and uses water supplied from the water supply reservoir or primary pool 12 to turn the prime mover .

An array of parallel spaced apart pumps 22 are arranged to be in fluid communication with the water supply reservoir or primary pool 12 and with the hydro turbine 20 via the water feed flow path 16. The pumps 22 are configured to pump water at a constant flow rate from the water supply reservoir or primary dam.

It will be appreciated that the pool 12 and the hydro turbine 20 are substantially level such that no head or at least a negligibly small head is measureable between them. This has the effect of cancelling out the pgh portion of the Bernoulli equation such that the total pressure as a result of water flow in the water feed flow path 16 is determinable from the static pressure effected by the water on the piping added to ½ pV², wherein V refers to the speed of water flowing past a specific point in the flow path Importantly, as shown in Figure 2, the water feed flow path 16 includes a dynamic pressure increase means in the form of a valve 24 proximate the prime mover of the hydro turbine 20. A gradual closure of the valve 24 ensures that the power generated by the hydro turbine 20 increases as the dynamic pressure of the water increases at the end of the water feed flow path 16. In this regard, it will be appreciated that the flow rate of water through the water feed flow path 16 until the water reaches the valve 24 flows at a constant rate. Accordingly, the valve 24 is configured to selectively close and thereby reduce the cross-sectional area through which the water flows at the end of the water feed flow path 16. The valve 24 incudes a valve member 28 which is movably positioned to permit back and forth movement of the valve member 28 within the water feed flow path 16 proximate the hydro turbine 20.

A reduction in cross-sectional area ensures that the speed of the water past a point at the end of the water feed flow path 16 immediately before coming into contact with the prime mover increases and with increased speed, the total pressure, as a result of water flow at the end of the water feed flow path 16, is increased. The increase in total pressure is directly proportionate to an increase in power generated by the turbine 20 of system 10. It is envisaged that the dynamic pressure increase means in an alternative embodiment of the invention may comprise a gradually decreasing diameter portion 26 provided in the water feed flow path 16 proximate or adjacent the prime mover. Figure 2 shows how the gradually decreasing diameter portion 26 and the valve 24 functions together to effect the desired increase in total pressure immediately before the prime mover of the hydro turbine 20 as shown in the respective positions of the valve head 28 relative to an opening to the prime mover of the hydro turbine 20. It is further anticipated that in another embodiment of the invention (not shown) the dynamic pressure increase means may comprise a plurality of dynamic pressure increase pumps which are provided in series relative to one another in the water feed flow path 16.

As shown in Figure 2, the valve 24 includes a stem 30 having a valve member 28 with a pear-shaped head 32 and a pointed toe 34 such that movement of the valve member 28 towards the prime mover defines two ports 36, 38 which gradually decrease in size, whereas movement of the valve member 28 away from the prime mover defines two ports 36, 38 which gradually increase in size.

The invention further provides for the series of pumps 22 to each include switching means (not shown) to permit a power source switch over. Preferably, the pumps 22 are diesel or petrol driven and configured to be switched over when desired to receive power from the hydro turbine 20 of the power generating system 10 such that no further diesel or petrol is required to run the pumps 22. A desired point where switch over is effected is where a set voltage, speed, frequency and power output is reached by the hydro turbine 20.

In Figure 1 , a plurality of pumps 22 in parallel are shown with check valves 40 to handle planned water flow via the water feed flow path 16. The planned water flow is typically a selected fixed or constant water flow rate.

It will be appreciated that the invention does not require a head to provide the kinetic energy for actuating the prime mover, but any low lying water source such as, for example, a lake, river, ocean, natural dam or man- made dam may be used as a water supply reservoir or primary pool 12. In essence, a method for generating power using the above described system 1 0 is also envisaged to be incorporated within the ambit of the current invention. This method is adapted to generate power through utilization of water flow, and comprises positioning a series of pumps 22 in a water feed flow path 1 6 and in fluid communication between a water supply reservoir or primary pool 1 2 and a prime mover of the system 1 0 as hereinbefore described, which water supply reservoir and prime mover lie in substantially the same plane. The method also includes ensuring that a dynamic pressure increase means or valve 24 is located in the water feed flow path 1 6 adjacent or proximate the prime mover. The method further includes powering the pumps 22 by means of an external power source such as diesel or petrol thereby to commence pumping of water through the water feed flow path 1 6 via the valve 24 and prime mover into a water return reservoir or secondary pool 14. Finally, the method includes actuation of switching means to switch over from external power supply to power provided by the hydro turbine 20 of the power generating system. The method may also include distribution to the grid of excess power generated by the power generating system 10.

In a further envisaged embodiment of the invention , the method includes use of any excess power generated by the power generating system 1 0 to drive one or more pumps of one or more similar power generating systems arranged in series to generate an increased amount of power.

The applicant believes that the method and system 1 0 of the present invention provide an effective and easy to use alternative to existing power generation systems. The monopoly for which protection is claimed is defined in the set of claims following below.