GB2454913A - Tide energy generator with flexible bladder - Google Patents

Abstract

A tidal power generation device has a flexible bladder 1 positioned on or near the sea bed. As the tide rises, water is allowed to flow through valves 2, 3 into a raised storage lagoon 5 via a turbine 4. As the tide then falls, water is allowed to return from the pool 5 via valves 7, 9 and another turbine 8, to the collapsible bag 1. A one-way valve 6 prevents water from returning in the wrong direction. Several systems can be run in parallel.

Description

Tidal Bladder Power Generation System This invention relates to a system to generate electricity using the differential height beveen low and high tides.

I

The tide holds enormous potential for energy generation, particularly in areas of high tidal variation.

Many methods of tidal power generation comprise of underwater mechanical devices, which are limited in several respects. Underwater mechanical devices, by the very nature of their construction (typically mild-steel), will suffer from corrosion, a major issue in the seawater environment. The initial capital outlay and the ongoing maintenance costs are high given the need to frequently refurbish I replace components. As a result, many systems are not commercially viable due to an unfavourable power output to cost ratio.

This invention relates to a simple collapsible tank or bladder, water lagoon and turbine set which can be located in any tidal location, It can be manufactured inexpensively and has low ongoing costs as it does not rely on complex underwater components. It can be of modular construction with modules being exchanged for example, during on-shore maintenance.

The system comprises of a collapsible tank or bladder, placed at a convenient height above or on the seabed, filled with water. The bladder has at least one outlet, controlled via an appropriate valve arrangemoni, to a turbine. The opposito.ide of the turbine connects to a water storage iagon, perhaps on the shore, some height H above the tidal variation range. Several systems can be located in parallel to one another. There is a return loop from the lagoon back to the bladder via a second turbine.

Figure 1 shows a side-elevation of the unit at low tide Figure 2 shows a side-elevation of the unit at high tide In figure 1 the bladder (1) is full of water and the control valve (2) prevents flow out of the bladder. As the tide level increases, the pressure inside the bladder increases and, at some time control valve (2) is opened and, controlled via the proportional valve (3), the water is driven out of the bladder, through a water turbine (4) into a storage lagoon (5), some height, H, above the tidal variation range. The one-way valve (6) prevents flow back into the bladder. This is the first phase of the power generation process. During this phase the shut-off valves (7) and (9) are closed.

In figure 2 a state of high tide has been reached: the water has been driven into the storage lagoon (5). At this point the process is reversed and the water is allowed to flow back from the lagoon, by opening the shut-off valve (7), through the turbine (8) and into the bladder (1). After this second power generation phase, the valve (9) is closed to prevent flow out of the bladder (1): this is the end of the power generation cycle and the entire cycle is then repeated.

Claims (4)

1. Claims 1. A system for power generation through the transfer of water or similar water-based hydraulic fluid by means of a compressing a collapsible storage device or bladder through vertical tidal movement.
2. 2. A system according to claim 1 where the collapsible storage device or bladder empties through a water turbine to a water storage lagoon.
3. 3. A system according to claims 1 & 2 where the rate of fluid transfer is controlled via an appropriate valve arrangment.
4. 4. A system according to claims 1, 2 & 3 of modular construciton to allow exchange of units for onshore maintainence.