GB2468864A

GB2468864A - Tidal power device uses long pipeline to produce airflow

Info

Publication number: GB2468864A
Application number: GB0904969A
Authority: GB
Inventors: Alan Newton
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-03-24
Filing date: 2009-03-24
Publication date: 2010-09-29
Also published as: GB0904969D0

Abstract

A tidal power system consists of a long pipeline 1 made up of a series of pipes 2 arranged parallel to the tide line and shore line and connected at their ends with 180 degree bends 3. The pipeline 1 extends from a low tide to high tide positions, so that the water fills and empties the pipe as the tide changes. An airflow is therefore produced which powers a multi blade wind turbine 9. The pipeline is connected to the turbine via a diffuser 7 which may draw in additional air (see figure 6). The increased length of the pipeline 1 increases airflow velocity compared with a similar pipe which runs straight between low and high tide positions.

Description

Tidal Wind Power This invention relates to a system of utilizing the rise and fall of the tides to develop a wind force to continuously drive a Wind Turbine.

Wind Turbines are driven by the force of the wind and as such give a varying degree of efficiency depending on the strength of the wind. Underwater Turbines are also in use to utilize the constant flow of tidal streams but the areas where tidal flow is sufficient and clear of marine traffic are limited. In addition both wind and tidal power systems are in general expensive to manufacture, install and maintain in addition to having a limited life. Both have raised objections from various bodies and this often results in long delays in having the systems accepted and put into service if at all.

However none of the existing wind or tidal power systems can claim to provide a continual unlimited and constant source of energy with nominal manufacturing costs, nominal maintenance costs, low installation costs and a nominal environmental impact.

According to the present Invention there is provided an open ended pipeline that stretches from the low water mark to the shoreline above the high water mark, specifically, but not restricted to areas where the low to high water marks are I to 2 km apart. The pipeline is made up of a series of pipes that run parallel to the tide line and shoreline but which are connected by 180 degree bends at the end of each pipe. This arrangement of pipes has the effect of artificially increasing the distance that the water has to travel from the low water mark to the high water mark. It is a known fact that the water inside the pipe will always be at the same level as the water outside the pipe and in order to do this the velocity of the flow of water within the pipeline will be increased significantly. This increase in velocity of the water flow within the pipeline ensures that the velocity of the air escaping the pipeline, as the water enters, is sufficient to drive the generator at a known and constant speed. The diameter of the pipeline is reduced slightly at the shore end to speed up the flow of air passing to and from the pipeline as the tide rises and falls. A shroud similar to an Aspirator (known technology), but not restricted to, is fitted round the reduced diameter end of the pipe drawing additional air, from outside the pipeline, into the flow from the pipe and this in turn is connected to a duct fitted round a multi blade turbine. The pipeline, at low water, will be virtually full of air and as the tide rises water entering the pipeline forces the air in the pipe to be expelled at the shoreline through the ducting and turbine to generate power. At high water the pipeline is full of water but as the tide recedes the water in the pipe also recedes and draws air back into the pipeline through the turbine continuing to drive it. The parallel pipes serve the purpose of increasing the effective length of the pipeline and therefore the velocity of the flow of water and escaping air is speeded up. Depending on the actual length of pipeline employed this would provide an effective continual wind speed of approximately 16 kilometers per hour at the turbine.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:-Figure 1. illustrates a typical cross section showing Low and High water marks.

Figure 2. illustrates a typical plan view showing the layout of the Centre Line of the parallel pipes from low water to high water.

Figure 3 Illustrates a cross section as in Figure 1 but with the pipeline in position.

Figure 4 Illustrates a section through the pipeline at mid tide showing the relevant water levels inside and outside the pipeline.

Figure 5 illustrates a section through the outer end of the pipeline below the Low water mark and immersed at all times.

Figure 6 Illustrates a section through the shoreline end of the pipeline indicating the reduction of the diameter, shroud, ducthg and turbine. This end is always above the high water mark.

Referring to the drawing the power generating system comprises a pipeline 1, which consists of a number of parallel pipes 2 connected by 180 degree bends 3, to form the continuous pipeline 1, that stretches from the low water mark 4 to the high water mark 5.

The effective length of the pipeline being increased greatly over a pipeline that would have extended in a straight line from the low water mark 4 to the high water mark 5. As the tide rises, from the low water mark 4, water enters the pipeline 1 and displaces the air that occupies the pipeline at low water. The displaced air is then forced through the reduced diameter neck' 6 at the shore end of the pipeline 1 increasing the velocity of the escaping air from the pipeline 1. Attached to the neck' 6 of the pipeline is a shaped shroud 7, creating an Aspirator effect, which draws more air to into the ducting 8 as it is dragged along by the effect of the air escaping the pipeline through the reduced diameter neck 6. The resulting velocity and volume of air being sufficient to drive the multi blade turbine 9 at a speed sufficient to generate electricity. At high water the pipeline 1 is full of water but once the tide recedes the water in the pipeline 1 also recedes and in so doing drags air in through the turbine 9, ducting 8, shroud 7 and reduced diameter neck 6 of the pipeline 1. It will be seen that the air iequired to fill the pipeline I will have the same volume as the air displaced when the water entered the pipeline 1 as the tide rose from the low water mark 4. The velocity of the airflow will then be constant and will permit the use of a dedicated and more efficient Turbine. Moving parts are restricted to the Turbine itself ensuring minimum maintenance, a predictable power source and longer in service time. Having a predictable and constant wind velocity within a narrow range permits the use of a dedicated, and therefore more efficient, turbine to suit the known wind velocity.

Claims

Claims 1. A Tidal Wind Power system that utilizes the natural effect of the rise and fall of the tide.
2. A Tidal Wind Power system as claimed in Claim 1 whereby the rise and fall of the tide is directed through a pipeline.
3. A Tidal Wind Power system as claimed in Claim 1 or Claim 2 where the pipeline is arranged such that the flow of water in and out of the pipeline is artificially speeded up due to the length of the pipeline.
4. A Tidal Wind Power system as Claimed in Claim 3 that utilizes known technology to increase the velocity of the air exiting and entering the pipeline as the tide rises and falls.
5. A Tidal Wind Power system as Claimed in Claims I to 4 that provides a continual and predictable power generating force.
6. A Tidal Wind Power system as Claimed in Claim 5 that utilizes a dedicated turbine to achieve the maximum efficiency for a known and continual air supply velocity.