FR2756325A1 - METHOD AND DEVICE FOR PRODUCING ELECTRICAL ENERGY FROM RENEWABLE ENERGY - Google Patents

Abstract

Process for producing electrical energy from renewable energy, characterized in that the following integrated operations are carried out, all operating in synergy: - renewable energy is captured, - this renewable energy is used to compress a gas, - This cold compressed gas is stored; - it is then destocked in a controlled manner, - the energy resulting from this destocking is converted into mechanical energy by means of a mechanical device, - said mechanical energy produced being in turn converted into electrical energy, and implementation of this process.

Description

The subject of the invention is a method and a device for producing electrical energy from renewable energy, in particular by storing potential energy.

 In the prior art, there are a number of devices for producing electrical energy from renewable energy. All these devices have in common that they seek to transform renewable energy directly into electrical energy, steam or hot water. In these devices, there is generally a significant loss of renewable energy used, and its conversion into electrical energy is generally done with a very low efficiency (of the order of 15%).

As a result, the devices of the prior art are relatively little used, or only for installations which cannot benefit from the general electrical supply.

To remedy these drawbacks in particular, the main object of the present invention is to propose a method for producing electrical energy from renewable energy which is such that the conversion of renewable energy into electrical energy is a series of integrated operations all working in synergy. In addition, part of the electrical energy obtained by this process is used for the performance of some of the operations necessary for this conversion.

Another object of the invention is to propose a device for implementing the method according to the invention. The device according to the invention is a device which operates "in a loop", that is to say in which part of the electrical energy produced is reused for the operation of the device.

The device is started up entirely from renewable energy, which is captured and stored. Thereafter, the system operating in a loop, Renewable energy will be used only to provide for the replacement of the potential energy which has been destocked, and to optimize the yields of the different stages.

This device is particularly interesting, insofar as, thanks to mechanical amplification, it functions as an "energy lever".

Thus, the choice of the size of the device does not depend solely on the size and intensity of the renewable energy likely to be captured, but on the final need for electricity. However, a good knowledge and perfect mastery of the natural deposit will be essential to optimize the performance of the system.

The integrated operations of the process according to the invention are as follows - renewable energy is captured, - this renewable energy is used to compress a gas, - this cold compressed gas is stored, - it is then destocked in a controlled manner, - converts the energy resulting from this destocking into mechanical energy by means of a mechanical device, - this mechanical energy produced being in turn converted into electrical energy.

The renewable energy used can be wind, sun, or any other renewable energy. This energy, captured, will be used to activate one or more pneumatic boosters which will compress a gas. The compressed gas is then stored cold in different tanks and at different pressures. Preferably, the gas used is air.

The destocking of the compressed gas is carried out by heating. This heating comes either from the calories which are recovered at various points of the device (notably at the level of the compressors or the turbines), or from the energy captured by solar collectors, or from an electrical resistance supplied by the electricity produced by the process according to the invention, or again by any other heating process.

The heated compressed gas will enter a fluid circulation device such as, in particular, a pumping system. This pumping system comprises one or more pumps such as in particular hydraulic pumps, worm pumps, diaphragm pumps, centrifugal pumps, mechanical pumps with single effect or double effect, the action of said pumps being possibly amplified by hydraulic cylinders.

The electricity produced by the process according to the invention is used in two different ways, part of this electricity is used to allow the realization or the optimization of certain stages of the process (compression of the gas, destocking of the compressed gas, operation of the turbomachine), The other part of the electricity is intended to be transmitted to the national electricity network or to be used on site in accordance with the regulations in force or possibly transmitted to an end user.

The device according to the invention is a device for implementing the method described above, characterized in that - it comprises a means of capturing renewable energy and of converting it so as to operate one or more pneumatic boosters, a means of storing cold compressed gas, then of destocking it by controlled heating to activate a device for circulating fluids which will expel a special fluid towards a turbomachine capable of producing electricity, and - The energy thus produced is used to supply the different means of said device.

Thus, the device according to the invention can be supplied by an external source, renewable energy, and / or by an internal source, the energy produced by this same device.

Furthermore, due to the "loop" use, the operator who monitors the device has the possibility of intervention and control at several levels, in particular by intervening on the flow rates of gas and fluid, and by regulating the amount of energy to be redistributed in the system, it can vary and optimize the operation of the device.

The detailed description which follows refers to the attached single figure which illustrates, without limitation, the invention, and which highlights other features and advantages of the invention.

This single figure is a diagram of the device for implementing the method of producing electrical energy from renewable energy according to the invention.

This unique figure represents a means 1 of capturing renewable energy. According to a particular embodiment of the invention, the renewable energy used is the wind, and the means 1 is a wind turbine. The energy thus captured is used to operate one or more pneumatic boosters or one or more compressors 2, which act to compress a gas, such as in particular air.

According to a particular embodiment of the invention, the compressed gas can be stored cold in different tanks 3a, 3b, 3c, and at different pressures.

The compressed gas is then destocked by heating. The different heating means that can be used are in particular an electrical resistance 4a, the heat coming from the heat recovery unit 4b, or the solar collectors 4c.

The compressed gas thus removed from storage actuates a mechanical device for circulating the fluids 5.

The mechanical fluid circulation device 5 consists of one or more suction and discharge pumps, such as hydraulic pumps and / or worm pumps, and / or diaphragm pumps, and / or centrifugal pumps , and / or single acting or double acting mechanical piston pumps. It is a pumping station operating in a closed circuit.

This or these pumps suck and discharge a hydraulic fluid 6 and expel this fluid towards penstocks 7.

Thanks to these pipes, the fluidel reaches continuously and under pressure in a turbomachine 8 such as in particular a turbocharger, a turbogenerator, or even a turbo-alternator.

According to another advantageous variant of the invention, the effect of the pumps is amplified by hydraulic or pneumatic cylinders.

The fluid sucked in and discharged by the pumps 5 is a special fluid whose chemical composition and viscosity are determined and constantly checked. The chemical composition is checked by frequent sampling and analysis. The viscosity is controlled by acting on the temperature of the fluid. Preferably, the fluid is of natural origin and biodegradable.

Another embodiment of the device according to the invention consists in using turbomachines as well for compressing the gas as for circulating the fluid or ejecting it towards the turbine / alternator group.

According to the device according to the invention, the electricity produced is reused to supply the pneumatic boosters which are used to compress the gas.

In the case where the heating of the compressed gas, with a view to its destocking, is carried out in particular by means of an electrical resistance, this resistance is supplied with the energy produced according to the method.

Finally, the energy produced is also reused to supply the turbomachine.

Claims (8)

1. A method of producing electrical energy from renewable energy, characterized in that the following integrated operations are carried out, all operating in synergy - we capture renewable energy, - we use this renewable energy to compress a gas , - this cold compressed gas is stored; - it is then destocked in a controlled manner, - the energy resulting from this destocking is converted into mechanical energy by means of a mechanical device, - said mechanical energy produced being in turn converted into electrical energy. 2. A method of producing electrical energy from renewable energy according to claim 1, characterized in that the renewable energy is wind. 3. A method of producing electrical energy from renewable energy according to any one of claims 1 or 2, characterized in that the gas is compressed by means of one or more pneumatic boosters, or by means of a turbomachine. 4. A method of producing electrical energy from renewable energy according to any one of claims 1 to 3, characterized in that the compressed gas is stored cold in different tanks and at different pressures. 5. A method of producing electrical energy from renewable energy according to any one of claims 1 to 4, characterized in that the destocking of the compressed gas is carried out by heating, said heating being provided either by calories which are recovered at various points of the device (in particular at the level of compressors or turbines), and / or by means of solar collectors, and / or by means of an electrical resistance and / or by any other suitable process. 6. A method of producing electrical energy from renewable energy according to any one of claims 1 to 5, characterized in that the mechanical device is a fluid circulation system such as in particular a submerged pumping system which includes one or more suction and discharge pumps such as, in particular, hydraulic pumps, worm pumps, diaphragm pumps, centrifugal pumps, single acting or double acting mechanical piston pumps, the action of said pumps being possibly amplified by hydraulic cylinders. 7. A method of producing electrical energy from renewable energy according to any one of claims 1 to 6, characterized in that the mechanical device is a turbomachine. 8. Device for implementing the method according to any one of claims 1 to 7, characterized in that it comprises a means 1 of capturing renewable energy and of converting it so as to operate one or more pneumatic boosters 2 which compress gas, said compressed gas 3 being stored cold, then destocked by controlled heating 4 to go to actuate one or more piston pumps 5, capable of expelling a special fluid 6 towards a penstock 7 which conducts the fluid in a continuous jet and under high pressure to a turbine / alternator group 8, The energy produced by said device serving to supply the booster (s) 2, the heating means 4 and / or the turbomachines and / or the turbine / alternator group 8.