OA16989A - System for energy production from renewable sources - Google Patents

Abstract

A system for energy production from renewable sources compristnq a support structure comprising a first pole and a second pole which are positioned vertically; a wind generator of vertical axis positioned on said first pole and a wind generator of vertical axis positioned on said second pole; said first pole and said second pole each comprising a connection element positioned at their summit; said connection element comprising a lower portion to be fixed to said first pole and to said second pole; said connection element comprising an intermediate portion and an upper portion; a first seat for a first cable being positioned between said lower portion and said intermediate portion; a second seat for a second cable being positioned between said intermediate portion and said upper portion; said first cable and said second cable being positioned mutually perpendicular; the ends of said first cable and of said second cable being fixed to the ground by posts fixed into the ground; said first pole and said second pole being each anchored to a post fixed into the ground by means of a hinge; said wind generator having a longitudinal central through hole to enable mounting on said first pole and on said second pole; said wind generator comprising a lower first locking ring for said wind generator, and an upper second locking ring for said wind generator; a respective bearing being associated with said first ring and with said second ring to enable said wind generator to rotate.

Description

The présent Invention relates to a system for energy production from renewable sources.

Commonly consldered to be renewable energy sources are hydroelectric, solar, wind, marine and geothermal energy, i.e. those sources the current use of which does not préjudice their future availabliity.

Those most commonly used are solar energy and wind energy.

A photovoitaic piant Is an electrical system which utillzes solar energy to produce 10 electrical energy by photovoitaic effect.

A solar follower is an electronically controiled mechanical device which favourably orientâtes a photovoitaic panel, a thermal solar panei or a solar concentrator relative to the sun’s rays.

A wind plant converts the kinetic energy of the wind Into electrical energy by the 15 use of a turbine of vertical or horizontal axis.

To achieve a worthwhlie electrical energy production, the aforesaid piants hâve to be of considérable dimensions.

This implles robust supports and a very large base as the system must be able to wlthstand adverse climatic conditions and in particular must wlthstand wind force. 20 The resuit is an enormous structure weight, a considérable base size, and Installation requiring time and speciaiized labour.

Moreover, lf such plants are positioned on an agrlcuiturai surface, considérable constraints are Imposed on working the land, resulting in disturbance and hindrance to such work.

The document W02010103378 describes a solar energy captation system supported by a network of ties.

An object of the présent invention Is to provide a system for energy production from renewable sources which enables total accessibliity of the underlying land.

Another object is to provide a system for energy production from renewable 30 sources which has an easily constructed support structure.

Another object is to provide a system which is simple to install and remove.

A further object 1s to provide a modular structure.

These and further objects are attained according to the invention by a system for energy production from renewable sources comprising a support structure comprising a first pôle and a second poie which are posltioned verticaliy; a wind generator of vertical axis posltioned on said first poie and a wind generator of vertical axis posltioned on said second pôle; sald first pôle and said second pôle each comprising a connection element positioned at their summlt; sald connection element comprising a lower portion to be fixed to said first poie and to said second pôle; said connection element comprising an intermediate portion and an upper portion; a first seat for a first cable being positioned between said lower portion and said Intermediate portion; a second seat for a second cable being positioned between said intermediate portion and said upper portion; said first cable and said second cable being positioned mutually perpendicular; the ends of said first cable and of sald second cabie being fixed to the ground by posts fixed into the ground; said first poie and said second pôle being each anchored by means of a hinge to a post fixed into the ground; said wind generator having a longitudinal centrai through hole to enable mounting on said first pôle and on said second pôle; said wind generator comprising a lower first locking ring for said wind generator, and an upper second locking ring for said wind generator; a respective bearing being associated with said first ring and with said second ring to enable said wind generator to rotate.

Further characteristics of the invention are described in the dépendent claims.

With the présent invention, large plants can be buiit on agricultural surfaces while maintaining the ground suitable for Its primary cuitivation purpose.

In this respect, the generators are able to be positioned at a certain height from the ground without however using demanding ioad-bearlng structures. The solution uses very thin pôles of about 5-6 m high, maintained in position by ties. The foundations to which the pôles and ties are coupied are redueed to concrète posts, ieaving the greatest space possible for crops.

In this manner rows of posts are formed on the ground having a passage gap of about 4,5 m. This guarantees total access to the underlying iand for circulation of agriculturai vehicies or, if this structure Is constructed on roads, perfect passage for vehicies using the road.

The wind generators are normaliy fixed to the ground individually, pôle by pôle. In contrast, the Applicant has realized that by using a common fixing system for several pôles, this could be iighter and avoid the necessary large foundations which dlsturb the underlylng agricultural crops.

ln addition, in an advantageous embodiment, the structure of a solar plant is also synergically utilized to locate the wind generators.

The characteristlcs and advantages of the présent Invention will be apparent from 5 the ensulng detailed description of one embodiment thereof, illustrated by way of non-limiting example ln the accompanyîng drawings, In which:

Figure 1 shows a system for energy production from renewable sources with two eiements, in accordance with the présent invention;

Figure 2 shows a system for energy production from renewable sources with two 10 éléments, ln accordance with the présent invention;

Figure 3 shows a structure for fixlng the support pôles and ties to the ground, ln accordance with the présent Invention;

Figure 4 shows a front view of a wind generator mounted on a support pôle, ln accordance with the présent Invention;

Figure 5 shows a perspective view of a wind generator mounted on a support pôle, In accordance with the présent Invention;

Figure 6 shows the half-fianges of the wind generator, in accordance with the présent invention;

Figure 7 shows an exploded view of a detail of the cable connection system of the 20 system In accordance with the présent invention;

Figure 8 shows an exploded view of a detail of the slidabie expansion joint of the system in accordance with the présent Invention;

Figure 9 shows a combined wind and solar energy production system;

Figure 10 shows a section through the turbine fixlng system;

Figure 11 shows a section through the turbine fixing system, including the electrical generator;

Figure 12 shows the system for fixing the wind pôles to the support pôle.

With reference to the accompanyîng figures, a system for energy production from renewable sources in accordance with the présent Invention comprises a plurality 30 of wind generators 10, ln particular of vertical axis, supported by a tensostructure.

Each wind generator 10 is supported by an iron support pôle 11 of diameter about

10-12 cm, having a thickness of 3-4 mm.

The support pôles 11 are malntained In position by a network of ties.

The support pôles 11 and the ties are fixed Into the ground preferably by posts 12 laid in the ground. The posts 12 consist of a concrète tube of length 2-3 m and diameter of about 30 cm driven Into the ground.

The support pôles 11 are fixed to the posts 12 by a coupling point 13 positloned at their base.

The foundatlon advantageously conslsts of a post 12 driven Into the ground or of a micro-pile formed on site, I.e. substantially a plug of concrète formed at a certain depth In the ground.

The post 12 Is provided at its top with a coupling point 13, comprising a drllled vertical plate 14. The support pôles 11 termlnate at their base preferably with two spaced-apart drllled vertical plates 15 cooperatlng with the plate 14. The plate 14 is inserted into the plate 15.

A pin 16 is inserted through the mutuaiiy facing holes of the plates 14 and 15 to enable the support pôles 11 to rotate about an axis parallel to the axis of the support pôle 11. The coupling point 13 hence forms a hinge.

Each wlnd generator 10 comprises a turbine 17 of vertical axis, for example of Savonius type, positioned coaxlally to the support pôle 11. The turbine 17 Is for example 2 m tall and has a diameter of 1 m.

The turbine 17 has a central longitudinal through hole for mounting on the support pôle 11.

At one end it also comprises an electrical generator 19. For fixing the turbine 17 to the support pôle 11 two half-fianges 9 are used, screwed thereto, namely one upper and one lower, which fix the turbine 17 to the pôle 11. Each pair of halffianges 9 acts as a support for a bearing 18, which enables the turbine 17 to rotate. Preferably, three or four structures 40 are fixed to said bearings 18 to define and maintain in position those wind-struck surfaces forming the wind blade. These flexible surfaces are malntained In shape by tensioning.

Said tensioning Is achieved by modifying the distance between the opposing said support structures for the blade surfaces, the upper with respect to the first central and the second central with respect to the iower, In order.

Tensioning is applied by adjusting appropriate screws inserted into the central ring.

Each pair of half-fianges 9 créâtes a ring of diameter slightly greater than the external diameter of the support pôle, fixed by at least three équidistant radial screws, which enable the rings to be coupled to the pôle and enable any nonlinearity of the pôle to be compensated. This enables pôles to be used which are not necessarlly perfectly llnear and hence avold costly pôle machinlng to ensure their llnearity within particular tolérances.

The rings fixed ln this manner enable coaxial fixlng points to be obtained Independently of the linearity of the support pôle, within certain limits.

Assembly of these rings ls simplified by a simple removable support structure fixed externally to the rings which maintalns them coaxial during the tightenlng of the screws fixlng the rings to the pôle.

The turbine 17 comprises the electrical generator 19 of toroidal type mounted directly on the pôle 11, ln proxlmity to the upper or lower rings 9. In particular, permanent magnets 41 are fixed to the bearing 18 to Induce, following rotation of the blade, an electrical field within the windings 42 of a stator connected to the corresponding ring 9, to form overall a polyphasé ring generator.

A fixing element (or connection crown) 29 is fixed to the upper end of the support pôles 11.

The fixlng element 29 présents a lower portion 21 for Its fixlng to the pôles 11, an Intermediate portion 22 and an upper portion 23.

A seat ls provided for a cable 24 between the lower portion 21 and the intermediate portion 22.

Between the Intermediate portion 22 and the upper portion 23 a seat ls provided for a cable 25 disposed perpendicular to the cable 24.

Hence the fixing element 29 ls formed such as to enable It to be mounted on the top of the pôle 11 and be traversed by the two mutually perpendicular taut métal cables 24 and 25.

Essentlally, the two taut métal cables 24 and 25 are incorporated Into the constituent components of the fixlng element 29.

The portions 21, 22 and 23 are joined together by screws. Previously, locking sleeves 26 (which increase the cable diameter) are applied to the cables and crlmped thereon ln the factory at predetermined distances with great précision, in accordance with the dimensioning scheduled by the design, ln this manner these sleeves form a sort of assembly template as the position of the sleeves already defines the distance between the support tubes 11 with great précision.

The seats for the cables 24 and 25 positioned in the lower portion 21, In the intermediate portion 22 and in the upper portion 23 are formed such as to be able to retain the locking sleeves 26.

Hence the cable Is used not only to support the pôles in position but also to hold 5 them in position at the correct distances apart with great précision, so avolding any adjustment of the distance between the tops of the pôles. This system reduces costs, simplifies assembly of the support pôles and ensures high précision.

Two mutually perpendlcular cables 25 and 25 arrive at each pôle 11. If dealing 10 with a latéral pôle, a cable Is fixed to the ground at a post 12. tf dealing with intermediate pôles, the cable proceeds to the next pôle.

For a plant with six pôles 11, steel cables of 18 mm diameter are used.

In a particularly advantageous embodiment of the présent invention, above the upper portion 23 of the fixing element 29 and latéral thereto two flanges are 15 présent comprising several holes, required for screws which fix the fixing element to a tube 30.

One flange 27 is used for fixing (supporting) the fixing element 29 to a tube 30, the other flange 26, opposlng the first, being used to fix (support) the fixing element 29 to another adjacent tube 30 in line with the first tube 30. In this 20 manner a continuous row of tubes 30 can be formed.

The horizontaliy positioned tube 30 can rotate about its own axis. To it there are connected a plurality of secondary tubes 31 fixed perpendicularly to the main tube 30 and able to rotate about their own axis by virtue of bearings.

A solar energy capitation panel 32 Is fixed to each of the secondary tubes 31.

The main tube 30 is made preferably of extruded aluminium (reduced weight), is m in length and is Internally hollow with a diameter of about 30-40 cm.

The secondary tubes 31 terminate on both sides of the main tube with flanges enabling the panels 32 to be mounted by screws and demounted.

The main tube 30 Is fixed at its ends to two support pôles 11 maintalned in 30 position by a network of tles.

For two mutually aligned main tubes 30 two latéral support pôles 11 and only one intermediate support pôle 11 are required.

At one end of the main tube 30 a motor is provided, suitably fixed to the tube, Its gearwheel engaglng ln a toothed semlclrcle (or toothed wheel) fixed to the fixlng element 29. This motor rotâtes the main tube 30 about Its axis.

More internally on the main tube 30 there ls another motor drlvlng a rack which rotâtes a pinion rigid with an axle fixed to the secondary tubes 31. This structure ls repeated for each pair of secondary tubes fixed to a main tube 30.

As an alternative to the aforedescrlbed solution, the gearwheels can be replaced by a rack with pulleys and belts (or chains).

At another end of the main tube 30 a slidable expansion joint 33 ls positioned, structured with telescopic éléments to enable Its expansion.

One telescopic element 34 ls fixed to the flange of the electrical generator 29 and another telescopic element 35 ls fixed to the main tube 30. The two telescopic éléments are separated by a polytetrafluoroethylene (PTFE) ring 36.

During assembly the slldable end ls fixed to the support structure such as to enable maximum expansion and maximum contraction.

The expansion joint 33 enables the main tube 30 to lengthen by thermal expansion without bearing on the support points, which are the fixlng éléments or, vice versa, enable the fixlng éléments to hâve a certain elastlclty of movement at the fixlng points, compensatlng In this manner the elastlclty of the cable.

As the main tube 30 is load-bearlng, It supports Its own weight, the weight of the internai llnkages, the weight of the rotary shafts to which the panels are connected and the weight of the panels. The mechanical characteristics of the tube are such as to wlthstand wind forces and snow loads, Independently of the position of the shafts.

The electrical connection cables for the various panels 32 and/or the turbines 17 are positioned inside the main tube 30, and carry away the current generated thereby.

The control system for the follower, Integrated into the main tube 30, ls able to constantly maintaln the panels orlentated towards the sun such that the sun is perpendicular to the captatlng surface of the panels, by known techniques deriving from the predictabiilty of ceiestlal mechanlcs, ln accordance with an algorithm based on the date and time, the geographical installation coordinates and the orientation to north of the main axis parallel to the ground.

Each main tube 30 comprises a control system integrated into the tube itself, and a recelver/transmitter able to communicate with nearby main tubes 30.

The control system Is provided with a receiver-transmitter preferably of ZigBee type by which it is able to communicate within a network consisting of several generators and one or more control centres. Each receiver-transmitter forms a node within the network able to communicate its own messages directly or to 5 retransmit messages received from nearby nodes. The radius of action of the receiver-transmitter must be such as to be able to communicate not only with the closest receiver-transmitters but, in case of a fault in one or more of them, to be able to communicate with more distant receiver-transmitters. For this purpose, the radius of action of each receiver-transmitter will be equal at least to four times the 10 length of the main tube 30.

A typical case could be the use of a structure combined with follower 32 and turbines 17, having main tubes 30 of length 12 m, in parallel rows spaced 12 m apart with pôles of height 5 m comprising five panels on one side and five panels on the other side of the main tube 30 in positions opposite the first to avoid 15 balancing problems, these being of size 1m x 2m (or even greater), spaced about

1,5 m apart. With this configuration there are no llmits to the type of crops or to the size of the agrlcultural machines able to pass below the plant.

By mounting the installation high, the generators and the electrical system are maintained far from the ground, so increasing the safety level for personnel and 20 enabling floodable or marshy land to be used.

The structure with ties can be achieved with only limited foundation work by using micro-plies or posts to be Inserted into the ground, hence avoiding the Imposing relnforced concrète foundation work required by traditional trackers sltuated on the ground.

When a row of posts has been laid and the cable which connects the row of posts together transversely has been passed through the tops of the posts (the cable then being locked to the ground at the beglnning and end of the row of posts), this solution enables the pôles to be ralsed from the ground by rotating them very easily on the pivots at the base of the pôles using a simple lever system. The 30 joint between the pôle and the foundation consists of a pivot which can be wlthdrawn to enable a pôle to be replaced and which, at the end of the plant's life, enables the structure to be dlsmantled and the foundation easily removed from the ground. The foundation is coupled at the fixed ring at its end to a lifting system which withdraws it vertically from the ground.

The plant is balanced along ail the movement axes and hence requires minimum force for Its movement. This results in low energy consumption and lighter mechanical members.

The support structure of the présent Invention does not require reinforced concrète foundation work, which makes a considérable impact on the underlying ground and ls dlfflcult to remove at the end of the plant operating life.

By vlrtue of the characteristics of the studied system, turbine installation ls particularly simple and economical. It takes place completely on the ground, both in the case of a new structure installation, by vlrtue of the installation system based on hlnging the base of the pôle, which maintalns the pôle lying on the ground during Installation, to be only afterwards placed ln the erect position, and ln the case of already existîng structures ln that said hinge enables the pôle to be decoupled from the hinge by the amount necessary to be able to insert the fixing rings and the toroldal shaped components of the turbine. This aspect is fundamental ln guaranteeing any maintenance operations for replacing said turbine components, operations which are economical as there is no need to demount the continuous tensostructure (so-called because it conslsts of continuous cables passing through the sockets positioned at the top of the pôles).

As stated the pôle does not hâve to withstand the enormous flexural stresses induced by the wlnd on the blade and transferred thereby onto the support post; consequently a normal pôle of steel or even wood of small dimensions can be used.

Moreover the pôle does not hâve to rotate but Instead It is the turbine mounted on the pôle itself which rotâtes, hence the pôle ls a very normal pôle.

For very lengthy pôles, such as in the présent case of about 6 m, two or even three turbines can be mounted one above another on a pôle using further fixing rings 9 or further bearlngs 18.

The materials used and the dimensions can be chosen at will according to requirements and to the state of the art.

The solar tracker concelved ln this manner is susceptible to numerous modifications and variants, ail falling within the scope of the inventive concept; moreover ail details can be replaced by technically équivalent éléments.

Claims (9)

1. A system for energy production from renewable sources comprising a support structure comprising a first pôle and a second pôle which are positioned vertically; a wind generator of vertical axis positioned on said first pôle and a wind generator of vertical axis positioned on said second pôle; said first pôle and said second pôle each comprising a connection element positioned at their summit; said connection element comprising a lower portion to be fixed to said first pôle and to said second pôle; said connection element comprising an intermediate portion and an upper portion; a first seat for a first cable being positioned between said lower portion and said intermediate portion; a second seat for a second cable being positioned between said intermediate portion and said upper portion; said first cable and said second cable being positioned mutually perpendicular; the ends of said first cable and of said second cable being fixed to the ground by posts fixed Into the ground; said first pôle and said second pôle being each anchored by means of a hlnge to a post fixed into the ground; said wind generator having a longitudinal central through hole to enable mounting on said first pôle and on said second pôle; said wind generator comprising a lower first locking ring for said wind generator, and an upper second locking ring for said wind generator; a respective bearing being associated with said first ring and with said second ring to enable said wind generator to rotate.

2. A system as claimed in claim 1, characterised by comprising locking sleeves which are crimped onto said first cable and onto said second cable at predetermined distances, said first seat and said second seat being able to retain said locking sleeves.

3. A system as claimed in claim 1, characterised by comprising an electrical generator connected to said wind generator fixed coaxially to said first pôle and to said second pôle.

4. A system as claimed in claim 1, characterised by comprising a load-bearing horizontal main tube which can rotate about Its axis; the ends of said main tube being coupled to the upper end of said first pôle and of sald second pôle; a plurality of secondary tubes fixed In a movable manner perpendicular to the main tube and able to rotate about their own axis; a solar energy capitation panel being fixed to each of said secondary tubes.

5. A system as claimed in claim 1, characterised in that said hinge comprises a drilled plate fixed to each of sald first pôle and said second pôle and a drilled u

plate fixed to said post flxed Into the ground; a pin being Inserted through the holes of said drllled plates.

6. A system as claimed In claim 1, characterlsed In that said first plate and said second plate hâve a height greater than 3 m, and more preferably greater

5 than 4 m.

7. A system as claimed In claim 1, characterised In that said connection element comprises a first latéral portion for flxlng said main tube and a second latéral portion for flxlng a possible further main tube.

8. A system as claimed In claim 1, characterised In that said main tube 10 comprises a slldable joint, which enables It to expand.

9. A System as claimed In claim 1, characterised In that sald first ring and said second ring each comprise two half-flanges which are fixed to sald first pôle and to sald second pôle.