A METHOD AND APPARATUS FOR PRODUCING ELECTRICAL ENERGY

The present invention relates to an apparatus and a method for producing electrical energy, by using in the apparatus and in the method a liquid, such as water, and movable vessels.

Prior art includes numerous different apparatuses for producing electrical energy by means of a liquid, such as water, that is flowing and/or under pressure. In water power plants the kinetic energy of flowing water is converted into the rotational energy of a rotor, which is further converted into electricity with a generator.

For example, in prior art pumping power station solutions, two water reservoirs at two different heights are connected with a pressure line. A functional pump is connected to the water turbine and to the generator by means of the same shaft. When there is little need for energy, water is pumped from the lower reservoir to the upper reservoir. In this case the generator functions as the motor of the pump. Conversely, however, water can be led from the upper reservoir to the lower reservoir via turbines, in which case electricity can be generated by means of a generator connected to the turbine.

A weakness in prior art is the low efficiency ratio, because energy is consumed in pumping a large mass of water, and in other losses such as friction, etc.

The purpose of the present invention is to disclose a method and an apparatus applicable to the method, with which electricity can be generated with a high efficiency ratio.

The apparatus according to the invention is characterized in that the apparatus contains an outer vessel that moves in an essentially vertical direction and an inner vessel, and in that the space between the outer vessel and the inner vessel, dividable with an isolating element, is filled fully or partially with a liquid, and in that a pretensioning element is connected directly or indirectly to the inner vessel and at least one hoisting element is connected to the outer vessel

with a connecting element, and in that at least one electric generator for generating electric current is connected directly or indirectly to the outer vessel.

The apparatus according to the invention is also characterized by what is disclosed in claims 2 - 8.

The method according to the invention is characterized by what is disclosed in claims 9 and 10, which describe the method.

In the following the invention will be described in more detail with the aid of the drawings 1 , 1 a and 1 b, in which Figs. 1a and 1 b are magnifications of the two points indicated in Fig. 1.

Thus the apparatus of the invention contains two vessels, one of which is inside the other.

The outer vessel 1 is open at its top and the inner vessel 2 inside it is smaller in volume than the outer vessel (smaller than the outer vessel by e.g. 2 cm in height and 2 cm in diameter). The inner vessel is a closed reservoir, but it can if necessary also be open.

The bottom of the inner vessel is wider than its diameter such that the diameter of the bottom is of the same magnitude as the diameter of the outer vessel less e.g. 2 mm. On the edges of the inner vessel are plate-like sealing pieces 3, which are provided with manually or electrically closable (motorized) shut-off valves 16 or similar isolating elements. The edge of the bottom of the inner vessel is provided with sealing rings 15, which obstruct liquid, such as water, from passing through the valve 16 when the valve is in the closed position.

A piston pin 4 is installed in the centre point of the cover of the inner vessel, at the top end of which are sealing rings (piston rings not shown in the figure).

A pretensioning element 5 such as a spring or pressure hose or pressure line is installed above the vessels, the length of which allows movement of the vessel between the upper and the lower positions.

A piston cylinder 13, which with the pin in the inner vessel functions as a so- called "sliding piston appliance" maintaining pressure, is disposed on the lower end of the pressure hose or similar.

The piston cylinder is fixed to the upper edge of the outer vessel with a connecting element/connecting elements 11 , such as e.g. with tension bars or similar. The connecting elements hold the lower end of the pressure hose in position with respect to the vessels.

The inner diameter of the pressure hose is the same as the inner diameter of the cylinder of the piston and the lower end of the hose is fixed to the cylinder of the piston.

The upper end 6 of the pressure hose is fixed in an airtight manner to unyielding ceiling 7 or a beam above the apparatus.

The outer vessel is suspended from a fixed ceiling 7 such that first the hoisting motors 8 are suspended from the ceiling with a cable and in connection with it the electric generators 9.

Hoisting motors 9 are fixed to the outer vessel with hoisting cables 10 such that in the hoisting phase of the apparatus, when the vessels are lifted, the vessels are raised with the hoisting motor and in the lowering phase said cables rotate electric generators.

The electricity produced by the electric generators is led onwards for use e.g. to the electricity network and in the hoisting phase of the hoisting motors the operating current is brought from outside the electricity network.

In the method according to the invention, the space 12 between the outer vessel and the inner vessel is filled with water, in other words when the vessels are in the upper position, the shut-off (motorized) valves 16 on the edge of the bottom of the inner vessel are opened. In this stage the water pressure between the bottoms of the vessels grows to the magnitude of the water column corresponding to the height of the vessel producing a force exerted downwards

to the bottom of the outer vessel and a force of the same magnitude exerted upwards to the bottom of the inner vessel.

The upward force of the inner vessel is transmitted to the air space inside the pressure hose via the piston pin 4 in the cover of the vessel. In the initial phase the tension bars 11 keep the lower end of the pressure hose 5 in its position.

The pressure inside the pressure hose grows to become as great as the force lifting the inner vessel. In this phase the force exerted on the piston and the downward force of the pressure hose cancel each other out, in which case the inner vessel remains in its position.

After this the vessels are allowed to descend under their own weight and under the influence of the force exerted on the bottom of the outer vessel for the distance permitted by the full length of the pressure hose.

As they descend the total force exerted downwards by the vessels rotates electric generators via the hoisting cables with the effect of the force, the distance and the time. The electrical energy thus produced is taken for practical application.

When the vessels have reached their lower position, the motorized valves 16 of the bottom flange of the inner vessel are closed.

In this case the pressure of the water column from the height of the side of the vessel is not exerted on the water mass between the bottoms of the vessels, but instead the force of the water mass exerted downwards is from the practical viewpoint only the weight of the water mass itself. Similarly the inner vessel no longer has lifting force.

As a consequence of this in this phase the force exerted downwards is in practice the mass of the vessels themselves plus the weight of the water mass.

After this the vessels are hoisted to their upper positions with the hoisting motors 8 by means of an external electric current.

The usefulness of the apparatus according to the invention arises from the fact that the force exerted downwards as the vessels descend is many times more than the force needed to raise the vessels (without the weight of the vessels themselves), in which case electricity can be generated with a good efficiency ratio by means of an electric generator.

It is obvious to the person skilled in the art that the different embodiments of the invention are not either limited solely to the examples described above, and that they may for these reasons be varied within the scope of the claims presented below.

In the method according to the invention the hoisting motor can if necessary function also as an electric generator when the inner vessel and also the outer vessel descend.