HK1189263B - Storing and transport device and system with high efficiency - Google Patents

Description

Efficient storage and delivery apparatus and system

The patent application of the invention is a divisional application of an invention patent application with the international application number of PCT/IB2011/051769, the international application date of 2011, 4 and 22, and the application number of 201180021307.4 in the Chinese national stage, namely 'efficient storage and conveying device and system'.

Technical Field

The present invention relates to a device for storing and transporting thermal energy, in particular thermal energy originating from the sun, preferably for the subsequent or simultaneous use thereof for the production of electrical energy.

Background

It is known to store solar energy concentrated, fixed or tracked by heliostats in receivers consisting of blocks of material with high thermal conductivity, usually graphite, for subsequent use. The block of material typically carries a suitably oriented cavity towards which the heliostat is directed. Furthermore, the block of receiver material is usually associated with a heat exchanger having a tube bundle that is not in the same block of material and is crossed by a working fluid or by a carrier fluid, usually water, which is liquid or gaseous at high temperatures. To produce steam or heat for an industrial facility, heat stored in the block of receiver material is transferred to the working fluid.

In systems for storing solar energy in graphite blocks of the above type, the temperatures involved may range from 400 ℃ to 2000 ℃. The upper temperature limit is defined by the thermal resistance of the heat exchanger, and in particular of its bundle of metal tubes. In particular, in connection with the temperature difference between the incoming fluid and the exchanger tubes, the thermodynamic conditions of the fluid may change so fast that strong pipe metal stresses (thermal and mechanical shocks) are generated, so that the heat exchanger is subjected to extreme physical conditions, creating a risk of excessive internal tensions and consequent breakage.

Furthermore, the difficulty of the system is to ensure the continuity of the heat removed by the accumulator, since the storage step is linked to atmospheric conditions and day/night cycles. Thus, known systems are not substantially versatile in terms of capacity to accommodate downstream energy demands.

Furthermore, in general, known systems are not optimized with respect to efficiency of use and conversion of the incoming electrical energy. Disclosure of Invention

The technical problem underlying the present invention is therefore to overcome the above mentioned drawbacks relating to the prior art.

The above-mentioned problem is solved by a device according to claim 1, by a plant, preferably a plant for energy production, comprising said device, and by a method according to claim 25.

Preferred features of the invention are set forth in the appended claims.

An important advantage of the present invention is that it allows to obtain the storage of thermal energy deriving from the sun in an efficient and reliable manner, minimizing the thermal stresses of the exchangers and increasing the heat exchange efficiency of the carrier fluid, both thanks to the use of a fluidizable granular bed which performs the dual function of heat storage and heat carrier. Based on this use, there are advantageous features of heat exchange of the fluidizable bed, as well as efficient heat convection transport after flexibility of the particulate phase. These characteristics are all linked to the possibility of giving the particulate solid rheological properties comparable to those of the fluid, in fact due to its fluidizability.

Furthermore, due to the possibility of controlled and selective fluidization of the particle storage device, better heat extraction continuity and optimized capacity to suit downstream energy requirements are ensured.

Furthermore, by combusting the gaseous fuel inside the fluidized bed, greater flexibility in energy production is possible, as described in detail below for the preferred embodiment.

Further advantages, features and methods of use of the present invention will become apparent from the following detailed description of some embodiments thereof, which is given by way of non-limiting example.

Drawings

Reference should be made to the accompanying drawings, wherein:

FIG. 1 shows a diagram of a system incorporating a preferred embodiment of an apparatus for storing and transporting thermal energy in accordance with the present invention; the system has a single receiving cavity;

FIG. 1a shows a plan view of the apparatus of FIG. 1 showing modules of the fluidizable particle bed of the apparatus;

fig. 2 shows a diagram of a system associated with a first embodiment version of the device of fig. 1, having a plurality of receiving cavities;

fig. 3 shows a diagram of a system associated with a second embodiment version of the apparatus of fig. 1, wherein a fluidizable particle bed is directly exposed to a receiving cavity and an additional bulk storage device arranged at the periphery of said fluidizable bed is provided;

FIG. 4 shows a diagram of a system associated with a third embodiment version of the apparatus of FIG. 1, in which a bed of fluidizable particles is directly exposed to a plurality of receiving cavities and an additional fluidized bed is provided for transferring heat to the tubes of a heat exchanger;

fig. 5 shows a diagram of a system associated with a fourth embodiment version of the apparatus of fig. 1, with dual fluidizable beds as in fig. 4, but with only a single central receiving cavity; and

figure 6 shows a device of the type shown in the preceding figures, inserted in a system not provided with fuel gas combustion and having a fluidizable gas closed circuit.

Detailed Description

Referring initially to fig. 1 and 1a, there is shown, by way of example, an apparatus for storing and transferring thermal energy according to a preferred embodiment of the present invention inserted into a facility for producing electrical energy, generally designated by the reference numeral 100.

The system 100 includes one or more devices for storing and transferring thermal energy, one of which is generally indicated by reference numeral 1 (for simplicity, only one device is shown in FIG. 1).

The device 1 is adapted to store thermal energy derived from solar radiation delivered/concentrated thereon, for example by means of a fixed or tracking heliostats.

The device 1 comprises a containment casing 2, preferably metal, and thermally insulated therein, so as to minimize the dissipation of heat towards the external environment.

The housing 2 carries a cavity 20 within which solar energy is concentrated.

A feed opening 21 for fluidizing gas is obtained in the housing 2, the function of which will be elucidated below.

At the top of the housing 2, the device 1 is provided with an outflow pipe 5 for the fluidizing apparatus, the function of which in this case will be elucidated below.

In the present example, and as better shown in fig. 1a, the device 1 has an overall cylindrical geometry, with the cavity 20 arranged in the centre and having a vertically running development.

The storage device 30 is arranged in the casing 2, preferably in the shape of a single block of graphite or comprising graphite, and is obtained, for example, by compacting a particulate material. In the present embodiment, the storage device 30 is arranged right in the cavity 20 so as to define its peripheral wall and is therefore directly irradiated by the solar radiation concentrated in this cavity 20.

At the inlet of the chamber 20, a plate 13 of a substantially transparent material, preferably quartz, may be arranged. Preferably, the plate 13 is suitably treated so as to be transparent to solar radiation entering the cavity and opaque to infrared radiation exiting from the cavity. The plate 13 thus has the function of insulating the receiving cavity 20 from the external environment, minimizing the radiation losses from inside the device 1.

The walls of the cavity 20 may also have a metallic coating 31, shown in a purely schematic way in fig. 1, or an equivalent coating, which keeps the storage device 30 free from oxidation and optionally blocks possible fine particle dispersion from the storage device, for example if powdered graphite is used.

Variant embodiments may provide different materials for the above-described memory block 30, as long as it has a high thermal conductivity and the ability to allow rapid heat transfer in the memory block and maximize the amount of stored heat.

In the housing 2 and limited to the single storage block 30, there is provided, according to the invention, a fluidizable particle bed, generally indicated by reference numeral 3. The bed of particles 3 is also suitable for storing thermal energy and is made of a material suitable for storing heat and which is according to the preferred features described below.

A tube bundle 4 of a heat exchanger through which, in use, a working fluid passes is arranged in or adjacent to the bed 3 of particles.

As mentioned above, the inlet 21 of the apparatus 1 is adapted to allow a fluidizing gas, typically air, to enter the housing 2 and in particular to enter the housing through the bed 3 of particles. In particular, the overall arrangement is such that the gas is able to move the particles of the bed 3 of particles so as to generate a flow/motion of the respective particles suitable for the heat exchange between the particles and the tube bundle 4.

At the inlet 21, a fluidizing gas distribution partition is provided, which is adapted to allow the gas to enter while ensuring support for the particles of the particle bed 3.

In the line with the outlet pipe 5 a dust separator 6 is arranged, which typically has an inertial impactor or equivalent device comprising a low load loss and cyclone operation, and which removes dust (de-pulverze) from the outlet gas, returning particles from the outlet gas into the housing 2.

The position of the tube bundle 4 with respect to the bed of particles, or more precisely with respect to the exposed surfaces of the tubes of the bed of particles, maximizes the heat exchanged, which is proportional to the product of the heat exchange coefficient and the surfaces involved in this heat exchange.

The tube bundle 4 may be absent or partially absent from the particle bed 3 (as shown in the example of fig. 1) or facing the particle bed 3. The choice depends on the mode of management of the plant and on the minimum and maximum height of the bed of particles, which varies on the basis of the velocity of the fluidization gas. In particular, as the speed increases, the surface area of the tube bundle involved in the heat exchange increases.

As shown in fig. 1a, the bed of particles 3 is preferably divided into a plurality of sections, optionally by partitions 330, the partitions 330 having a modular structure which allows selective fluidization therein by dividing the fluidization region and feeding gas only in the portion of the fluidized bed which can be selected according to specific operating needs.

The feeding of the fluidizing gas to the inlet 21 of the apparatus 1 takes place through feeding means of the plant 100 comprising a feeding duct 210 connected to forced circulation means 8, the forced circulation means 8 being typically one or more fans. In particular, the feeding device defines a circuit for collecting gas, preferably air coming from the environment, which enters the inlet 21 of the apparatus 1 and, downstream thereof, passes through the pipe 5 to the dust-extraction device 6 and reaches the heat exchanger 7 for preheating the working fluid. The inlet for the fluidizing gas is further provided with a manifold 14 or an air hood.

The feeding device can be selectively controlled for varying the fluidization gas velocity and thus the overall heat exchange coefficient between the particle bed 3 and the tube bundle 4.

In fact, by varying the transverse gas component velocity, it is possible to control and modify the overall heat exchange coefficient of the fluidized bed towards the storage block and the working fluid, with the consequent flexibility of adjustment of the amount of thermal power transferred. This effect is particularly useful for regulating the heat transferred from the storage device to the working fluid through the bed of particles, due to the solar radiation conditions depending on the required load.

Preferably, the fluidization conditions of the bed of particles are boiling, or in any case, that maximizes the heat exchange coefficient and minimizes the transport of particles in the fluidizing gas. For this purpose, the choice of the bed material is based on the thermal characteristics of high thermal conductivity and the diffusivity of the material constituting the particles, and in particular on the low abrasiveness, to meet the need to minimize the particle erosion phenomena of the bed and of the storage mass, in order to limit the production of particles and to limit the transport of particles into the fluidizing gas. Based on these teachings, the preferred constructive privilege uses for the bed 3 of particles materials inert to oxidation, in regular shape, preferably spheroids and/or preferably in the size range 50-200 microns; and the size is preferably intrinsic, not resulting from aggregation of smaller sized particles.

If desired, it is possible to provide a surface of highly thermally conductive material 32 to protect the portion of the reservoir mass involved in the reaction of the bed of particulate material.

As regards the working fluid, in the present example and in the preferred construction, it is water that passes through the tube bundle 4 and is evaporated by the effect of the heat exchange in the fluidized bed.

The working fluid circuits are provided with pipes 90 which form the tube bundle 4 within the plant 1 and which, in the example given in fig. 1, provide a steam turbine 10 connected to a generator, a condenser 11, a feed pump 12 and a heat exchanger 7 functioning as a preheater.

The entire apparatus 1 is thermally insulated and, if the material constituting the storage mass 30 and/or the bed 3 of granules is not inert to air (that is to say able to withstand oxidation phenomena), it is necessary to evacuate the air from the internal environment of the apparatus 1 and/or to obtain a slight overpressure of the internal environment by means of an inert gas. In this case, the fluidizing gas of the bed of particles must be inert and, as shown in fig. 6, the feeding circuit of said gas is closed.

The device 1 is provided with a system for closing a receiving cavity, thermally insulated (the system is not shown in the figures), which prevents heat from diffusing from the cavity to the external environment. Optionally an automated overnight start of the closed system.

In a variant embodiment, the storage device 1 is associated with a secondary reflector/concentrator, not shown in the figures, which is located at the inlet of the cavity 20 and thus around the inlet of the casing 2 allowing the radiation concentrated by the heliostats to enter.

This secondary reflector allows to recover a portion of the reflected radiation that would not have reached the cavity 20, thanks to internal mirrors suitably shaped, for example in a parabolic or hyperbolic profile. In fact, due to surface imperfections and/or surface alignment, a part of the radiation reflected by the heliostats does not enter the cavity entrance and will therefore be lost.

A possible alternative would be to obtain a wider cavity entrance; however, this solution would considerably increase the radiation of the cavity to the outside environment, with the result that a considerable part of the power is lost. The use of a secondary concentrator also allows for the release of design constraints on heliostat bow, which results in variations in the size of the beam reflected on the receiver. Furthermore, the use of the secondary concentrator allows the use of a flat heliostat whose area does not exceed the entrance surface. This aspect greatly affects the total technical cost: flat mirrors are very inexpensive, and the cost of a heliostat typically accounts for more than half of the total system cost.

The direction of the local concentrator described above is in terms of the orientation and position of the cavity facing the heliostat field.

The combined use of the above-mentioned quartz plate 13 or other transparent material and the secondary concentrator arranged at the inlet of the receiving cavity is particularly advantageous, since they both contribute to an increased absorption of the available solar energy.

The device of the invention, here designated with reference numeral 102 and inserted into the installation 101, can be provided with a plurality of receiving cavities, illustrated for the example in the figures as two cavities 201 and 202, based on a further variant embodiment with reference to fig. 2. The presence of multiple receiving cavities allows to mitigate the heat flow affecting the inner walls of the single cavity and to reduce the working temperature, increasing the competitiveness and performance of the material used as cavity coating. In this case, the features described above with reference to the embodiment of fig. 1 and 1a with respect to the single cavity 20 are the same as for each of the cavities 201 and 202.

Unlike the storage device described with reference to fig. 1, the device 102 is provided with a centrally arranged particle bed 3 and with a single or granular storage mass, indicated with reference numeral 301, arranged transversely to the particle bed.

Along the working fluid line of the installation 101, there is arranged a degassing device 40 which is connected to the steam turbine 10 and has upstream thereof a suction pump 120 or equivalent.

For the other parts, the device 102 and the system 101 are similar to those already described with reference to fig. 1.

With reference to fig. 3, a further variant embodiment of the device of the invention, indicated with reference numeral 104 and inserted in the system 103, is provided with a fluidizable bed 3 of granular material to receive solar thermal energy directly from the surface of the receiving cavity 20 and therefore, in addition to functioning as a heat carrier, also functioning as a storage means. Any possible additional storage material, indicated with reference numeral 300, may be positioned at the periphery of the fluidizable bed. In this configuration, the bed of particles extracts thermal energy from the side walls of the receiving cavity while being fluidized, and transfers the thermal energy to the tube bundle of the heat exchanger and the surface of the storage device 300 (if provided). As mentioned above, the heat transfer rate, i.e. the heat exchange coefficient, is adjusted by the fluidizing air velocity.

When solar radiation is present, solar energy is concentrated to the cavity 20 and, through fluidization of the particle bed, the thermal energy is partly transferred to the tubes of the heat exchanger 4 and partly to the storage device 300. The direction of heat exchange is from the chamber 20 to the bed 3 of particles and thus to the exchanger 4 and to the storage device 300, which is at a lower temperature than the granular material 3 and is in direct contact with the chamber 20.

In the absence of solar energy, for example at night, by fluidizing the bed of particles 3, the hot passage takes place from the storage means 300 to the bed of particles 3 and thus to the tubes 4 of the heat exchanger, which ensures the continuity of the plant operation and of the steam distribution and of the thermal power coming from the plant. Thus, in the absence of solar energy concentrated to the receiving cavity 20, the heat transfer direction is reversed, proceeding from the storage device, which has stored the thermal energy transferred by the fluidization of the bed of particles during the insulation time, towards the particles of the bed of particles, i.e. towards the heat exchanger tubes.

For the other parts, the apparatus 104 and the system 103 of fig. 3 are similar to those already described with reference to fig. 1 and 2.

With reference to fig. 4, a further variant embodiment of the device of the invention, denoted by reference numeral 106 and inserted in the installation 105, is provided with a first and a second fluidizable bed, denoted by reference numerals 304 and 305 respectively, which are arranged concentrically, the first and the second, and which have the function of a storage device and a heat carrier, respectively.

With reference always to fig. 4, the granular material constituting the first fluidizable bed 304 receives solar thermal energy directly from the surface of the receiving cavity, denoted herein by reference numerals 203 and 204, and which acts as a storage device. On the other hand, the heat transfer is performed by a second fluidizable bed 305 arranged inside the first fluidizable bed 304, and the tubes 4 of the heat exchanger are located in this second fluidizable bed 305. This configuration allows greater system flexibility in the storage step and in the release of heat to the carrier fluid due to the possibility of independent action on the reaction and independent action on the velocities of the fluidizing gas of the two beds of granular material and/or sections of the beds.

A similar construction is the version shown in fig. 5, where the positions of the two beds, i.e. the storage and carrier beds, are inverted compared to the situation of fig. 4, since in fig. 5 a single receiving cavity 205 is provided in a central position.

As mentioned above, the fluidized beds may also be separated not by physical baffles 330, but by separate actuating modular zones by dividing the fluidizing gas.

For any of the configurations described, the size of the apparatus, in particular the size of the granular bed, the fluidization gas velocity range, the number of storage devices (solid or granular) optionally associated with passing through the fluidized bed, and the surface of the heat exchanger are all such as to ensure the storage of heat during periods of sunshine and to transfer this heat to the heat exchanger through the fluidized bed particles during the night.

Furthermore, as mentioned above, for the modular structure using fluidized beds and for any of said structures that adjust the fluidization velocity of the particles of each section, it is possible to regulate the amount of thermal energy transferred to the pipes, by means of their selective and/or differentiated fluidization, to select one or more sections using thermal energy storage or transfer, thus ensuring continuous operation of the plant of the invention.

Furthermore, for the plant of the invention described so far with a plurality of plants, the possibility of adjusting the heat exchangers delivered to each plant and of maintaining the heat required for the temperature and pressure of the continuously produced steam allows the advantages of maintaining, reducing or increasing the energy production.

In the case of a multiple-plant based system, the size and operating logic of the multiple plants are adjusted so that a predetermined energy production is obtained even in the absence of solar radiation.

In the above description reference has been made, by way of example, to the incorporation of the device in a stand-alone system for the production of electrical energy. However, it will be appreciated that the possible applications of the present apparatus are broad and relate to the production of steam or thermal energy for industrial systems, such as for thermoelectric plants, desalination systems, remote heating (tele-heating) and the like.

Legislation regulating energy production from renewable sources dictates that the share of this energy that is allowed to be produced by burning fossil fuels is minimal. Typically, in prior art arrangements, this operation is performed in a production unit that is independent of the main production system.

On the contrary, an important advantage of an energy production facility based on the device of the present invention lies in the possibility of burning gaseous fossil fuels inside a fluidized bed.

For this reason, for each of the embodiments described herein with reference to the various figures of fig. 1-3, these figures show the combustion gas 401 inlet located at the fluidizable bed acting as a heat carrier and directly at the fluidizing gas feed channel. For the variants of fig. 4 and 5, the combustion gas feed may be provided to one or both of the fluidizable beds, as illustrated.

All the figures relating to the description show a schematic view of the construction, so that they may not show components such as valves or sensors, which have to be provided for the regular regulation of the fluid circuit.

In this regard, it should be better understood that, in addition to the high thermal "diffusivity" of the granular bed, the fluidized bed system has the dual advantages of high heat exchange rate at the bed-storage device or bed-bed interface and at the tube surfaces not in the granular bed, and the essential characteristics regarding the possibility of rapid loading/unloading of the thermal accumulator in short operating steps.

The invention thus allows the storage of thermal energy within the bed of particles and the variation of the thermal power output from the system by adjusting the fluidisation velocity of the particles.

Likewise, the use of multiple cavities of appropriate dimensions and oriented towards the mirror region allows to reduce the incident heat flow and to mitigate the maximum temperatures that would affect a single cavity, making the choice of coating techniques and materials for the walls of this cavity more competitive.

The modular structure of the fluidized bed then allows to actuate one or more sections with considerable management redundancy and makes the system availability less dependent on atmospheric conditions and on the availability of the generator.

Furthermore, the simultaneous combustion of the fuel gas in the fluidized bed of the device allows to keep the system energy production constant even during periods of low insulation.

Finally, it is understood that the invention also provides a storage and heat exchange method, defined by the claims that follow, and which has the same preferred features described above with respect to the various embodiments and versions of the device and installation of the invention.

The present invention has thus far been described with reference to preferred embodiments. It is to be understood that other embodiments are possible within the same inventive scope, as defined by the scope of protection of the claims below.

Claims (30)

1. An apparatus (1) for storing and transferring thermal energy, said apparatus being adapted to receive solar radiation, said apparatus (1) comprising:

a housing case (2);

a bed of particles (3), suitable for storing thermal energy, housed inside said containment casing (2); and

at least one feed inlet for feeding a fluidizing gas through the particle bed (3),

the overall arrangement is such that, in use, the fluidizing gas moves the particles of said bed (3) of particles, causing or promoting heat exchange between the particles and a tube bundle (4), a working fluid flowing in said tube bundle (4);

characterized in that the apparatus further comprises a compartment of the fluidization region adapted to allow selective and/or differential fluidization of one or more portions of the particle bed by a fluidization gas.

2. The apparatus (1) according to claim 1, wherein the particles of the bed (3) of particles consist of a granular material of substantially regular shape.

3. The device (1) according to claim 1, wherein the particles of the bed (3) of particles have a size of the order of 50-200 microns.

4. The apparatus (1) according to claim 1, further comprising another storage device in the form of a monolithic block (30).

5. Device (1) according to claim 4, characterized in that said monolithic body (30) is or comprises graphite.

6. Device (1) according to claim 4, characterized in that said monolithic body (30) is obtained by compacting a material in granular form.

7. The apparatus (106) according to claim 1, further comprising a further storage device in the form of a further fluidizable particle bed (304) housed inside said containment casing (2), said particle beds (305, 304) being arranged concentrically to each other.

8. Device (1) according to claim 4, characterized by the fact that it has one or more receiving cavities (20) inside which the solar radiation is concentrated or inside each of said cavities (20).

9. Device (1) according to claim 8, characterized by comprising a plate (13) of substantially transparent material, arranged in correspondence of the mouth of the or each cavity (20).

10. Device (1) according to claim 9, characterized in that the or each plate (13) is permeable to the solar radiation entering the respective cavity (20) and impermeable to the infrared radiation emitted from said cavity (20).

11. The device (1) according to claim 8, comprising a secondary solar radiation concentrator located at the inlet of the or at least one receiving cavity (20).

12. An apparatus (102) according to any one of claims 8-11, wherein said further storage device (30) is arranged directly in correspondence of said one cavity or at least one of said cavities (20).

13. The device (104) according to any one of claims 8-11, wherein the particle bed (3) is arranged directly in correspondence of the or at least one of the cavities (20).

14. Device (1) according to any one of claims 1-11, characterized by an outlet duct (5) for the fluidizing gas.

15. The plant (1) according to any one of claims 1 to 11, wherein said tube bundle (4) comprises one or more heat exchange elements receiving or adapted to receive a working fluid and arranged in contact with said bed of particles (3) and/or, in use, by said bed of particles (3) when said bed of particles (3) is fluidized by said fluidizing gas.

16. A plant (100) for producing steam or heat for industrial use, comprising one or more devices (1) according to any one of the preceding claims.

17. The plant (100) according to claim 16, comprising means (210, 8) for feeding the fluidizing gas via at least one inlet (21) of the device (1).

18. The plant (100) according to claim 17, wherein said feeding means comprise means (8) for the forced circulation of said fluidization gas.

19. The plant (100) according to claim 17, wherein the feeding device is selectively controllable to vary the velocity of the fluidizing gas.

20. The plant (100) according to any one of claims 16 to 19, comprising means (6) for dedusting the fluidizing gas.

21. The plant (100) according to any one of claims 16 to 19, comprising means for selectively feeding a fluidizing gas to selected portions of the bed (3) of particles.

22. The plant (100) according to any one of claims 16 to 19, comprising means (401) for feeding combustion gases inside said casing (2) of said device (1).

23. The plant (100) according to any of claims 16 to 19, wherein the plant is a power generation plant.

24. A method of storing and then exchanging heat derived from the sun, which method provides for the use of a bed (3) of particles adapted to receive and store thermal energy derived from the sun, and for the fluidisation of the bed (3) of particles to cause or promote heat exchange between the bed (3) of particles and a tube bundle (4) of a heat exchanger;

characterized in that the method provides differential fluidization of selected portions of said bed (3) of particles.

25. Method according to claim 24, characterized in that the fluidization is performed by controlled feeding of fluidizing gas.

26. Method according to claim 24, characterized in that a working fluid, which is water and/or steam, flows inside the tube bundle (4).

27. The method according to claim 24, characterized by the step of: a step of storing thermal energy in a storage device (30, 3) during insolation, and a step of transferring heat from the device (30) to the tube bundle (4) by fluidizing the bed (3) of particles in the absence of solar radiation.

28. The method according to claim 24, characterized by providing the use of one or more devices (1) or said installation (100) according to any of claims 1-23.

29. The method according to claim 24, characterized by providing combustion of gaseous fossil fuel inside the particle bed (3) of the device (1).

30. A method according to any of claims 24-29, characterized in that in order to obtain a constant energy production, there is provided the step of storing thermal energy and concomitantly or with a delay of transferring said thermal energy to a heat exchanger.