GB2441768A

GB2441768A - Wind powered, roof mounted electricity generator

Info

Publication number: GB2441768A
Application number: GB0623841A
Authority: GB
Inventors: Neil O'neil
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-11-29
Filing date: 2006-11-29
Publication date: 2008-03-19
Anticipated expiration: 2026-11-29
Also published as: GB0623841D0; GB2441768B

Abstract

An electricity generating device 10 comprises a wind turbine rotor 14, connected to an electric generator (16, figure 2), mounted within a hollow housing 12, the housing 12 having a plurality of openings defined in walls 24, 26 thereof. The device 10 has means to be physically and electrically connected to one or more like devices. The housing 12 may comprise a substantially rectangular box with a pitched roof 28 which overhangs the walls 24, 26. The device 10 is intended to be mounted on the ridge of a pitched roof of a building (figure 7), with a ridge tile (48, figure 7) located on the pitched roof 28 of the housing 12. Each device 10 may comprise a plurality of rotors 14 which may be mounted horizontally and/or vertically. The connection means may comprise corresponding projections (30, figure 5) and recesses (32, figure 5) in end walls 20, 22 of the housing 12, and an electrically conductive base (18, figure 5). Generated electricity may be stored and supplied to a building the device is mounted on, or to an external electricity supply such as the national grid.

Description

2441768

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Modular device for generating power from the wind

The present invention relates to a modular device for generating electrical power from the wind and an apparatus 5 for supplying electrical power comprising an array of such devices. In one embodiment, the invention relates to power generation apparatus for domestic use which can be placed beneath a ridge tile situated on the top of the roof of a building, where wind speed is higher. However, the 10 principles involved are readily applicable to other applications such as those in the automotive", nautical and aerospace fields.

The use of small-scale wind turbines for domestic situations 15 is well known in the art. However, these devices have several major drawbacks. A key drawback is that they are visually obtrusive. They also have limitations with regard to scalability. The larger the building, the larger the turbine or the larger the number of turbines required, 20 adding to the degree of visual obtrusion. There has also been recent criticism as to whether such devices produce a useful amount of power.

The present invention addresses these drawbacks by providing 25 small-scale power generation units which are visually unobtrusive and which can be networked together to provide a cumulative output. In the preferred embodiment the units are integrated into the roof structure of a building such that they are virtually hidden from view. More particularly, the 3 0 invention has been designed to be located underneath a standard ridge tile at the top of a roof. However, as

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mentioned above, it can be applied to a, variety of applications.

The present invention provides an electricity generating 5 device comprising a hollow housing, a plurality of openings defined in walls of the housing and shaped to promote fluid flow through the housing, at least one rotor rotatably mounted in the housing and connected to a generator in the housing which is operable to generate electricity in 10 response to rotation of the rotor caused by fluid flow through the housing, and interconnection means for physically and electrically connecting the device to one or more like devices.

15 Preferably, the rotor comprises a spindle and a plurality of flow-capture surfaces configured to cause rotation of the spindle when acted upon by fluid flow from any of a plurality of different directions.

20 The device may comprise a plurality of rotors, configured to maximise output from the generator.

In this case, at least two of the plurality of rotors may be configured and/or oriented differently from each other.

25

In a preferred embodiment, the housing comprises a substantially rectangular box with a pitched roof, dimensioned so as to be locatable at the apex of a pitched roof of a building, beneath a ridge tile.

Preferably, in this case the openings are formed in opposing side walls of the housing and the pitched roof of the housing overhangs the openings. This arrangement optimises the wind-tunnel effect ensuring efficient use of all 5 strengths of fluid flow, regardless of direction.

The interconnection means may comprise a projection extending from one wall of the housing and a corresponding recess defined in an opposing wall of the housing.

10

The interconnection means may further comprise an electrically conductive path provided in the base of the housing.

15 The present invention also provides a modular electricity generating apparatus comprising a plurality of electricity generating devices of the type described above,

interconnected to form an array, and means to connect the array to a power control device wherein the power control 20 device comprises means to store electrical energy generated by the array and means to selectively supply electricity to a first user or a second user.

Preferably, the power control device comprises an 25 uninterrupted power supply device operable to supply electricity to a first user in response to demand therefrom utilising electricity generated by the array when sufficient is available from the array, or otherwise utilising electricity supplied by the second user.

The uninterrupted power supply device may also be operable to supply electricity back to the second user if the

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quantity of electricity generated by the array exceeds the demand of the first user.

Typically, the first user comprises the electrical system of 5 a structure to which the array is connected and the second user consists of an external electricity supply such as the national grid.

The invention will now be described in detail, by way of 10 example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of one embodiment of power generation device in accordance with the present invention;

15

Figure 2 is a side view, partly in section, of the device of Figure 1;

Figure 3 is a perspective view, with parts cut away for 20 clarity, of a second embodiment of power generation device in accordance with the present invention;

Figure.''4 is a perspective view, with parts cut away for clarity," of a third embodiment of power generation device in 25 accordance with the present invention;

Figures 5a and 5b are perspective detail views of the ends of the power generation device of Figure 1 showing the interconnection means;

30

Figure 5c is an underneath view of a series of the devices of Figures 5a and 5b connected together;

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Figures 6a and 6b are perspective and end views respectively of a conventional pitched roof;

5 Figures 7a and 7b are perspective and end views respectively of a pitched roof incorporating the power generation apparatus of the present invention;

Figure 8 is a perspective view of a power generation device 10 and terminal block; and

Figure 9 is a block diagram illustrating a power control unit for use with the power generation devices of the present invention.

15

One embodiment of a power generating device 10 in accordance with the present invention is shown in Figure 1 and 2. The device 10 comprises a housing 12, a turbine rotor 14, and an electric generator 16 (shown schematically in Figure 2).

20

The housing 12 is a substantially rectangular box with a base 18 and end walls 20, 22. The sides 24, 26 are partially or completely open. The open sides 24, 26 of the housing 12 may be covered by a fine mesh to prevent ingress of debris 25 that might inhibit rotation of the rotor 14. The housing 12 has a pitched roof 28 which is overhanging and extends laterally beyond the side 24, 26 and base 18.

The power generating device 10 includes interconnection 30 means on the end walls 20, 22, omitted from Figures 1 and 2 for clarity but best shown in Figures 5a and 5b. In particular, a male connection 30 protrudes from one end wall

20. This is able to mate with an adjacent device 10 by means of corresponding female connection 32 formed in the opposing end wall 22. It will be appreciated that other forms of interconnection could also be used.

In use, the interconnection means 30, 32 allow a series of devices 10 to be locked together in a linear array as shown in Figure 5c.

The housing 12 may be made from any suitable lightweight,

/

yet strong and weather-impervious material. The base 18 may be formed of an electrically conductive material, or it may incorporate one or more electrical conductors, such that when a series of devices 10 are interconnected as in Figure 5c a conductive path is provided along the length of the array, as described further below.

In one embodiment, the turbine rotor 14 comprises a spindle 34 and a number of blades 36 as shown in Figure 2. The spindle 34 is rotatably mounted between the end walls 20,22 of the housing 12 with its longitudinal axis L substantially horizontal in use. The spindle 20 is preferably supported in bearings (not shown) to minimize friction and maximise efficiency.

The spindle 34 is connected to an electric generator 16, typically of the type comprising a metallic coil located between the poles of a magnet, although any suitable form of generator could be used. Preferably the generator is miniaturised and located within an end wall 20 or 22 of the housing 12.

The precise form of the spindle 34 and blades 36 will be designed to maximise the efficiency of the power generation device 10. Thus, the blades 36 should be shaped so as to capture whatever airflow passes through the housing 12 and 5 so to cause rotation of the spindle 34 regardless of the direction from which the airflow hits the blades 36 or the strength of the airflow.

In this example, the spindle 34 and blades 36 are 10 illustrated as a unitary body of fairly complex geometry, with a variety of curved and flat flow-capture surfaces. Thus, there are surfaces 38 for capturing airflow entering the housing 12 at right angles to the longitudinal axis L of the spindle 34, while surfaces 40 capture airflow entering 15 at another angle to the longitudinal axis L.

However, the turbine rotor 14 may take any form found to produce the best performance. For example, the spindle 34 could be mounted such that its longitudinal axis L is 20 substantially vertical in use. In this case, it may be preferable to include more than one turbine rotor 14 in each device 10, as in Figure 3, which shows three turbines side by sidg. These are shown as more traditionally shaped turbines' with a spindle and a plurality of blades 36, 25 although they may be of any suitable form.

Alternatively, a combination of horizontally and vertically mounted turbines may be used as in Figure 4. Each turbine rotor 14 may take the same form, as in Figure 3, or a 3 0 combination of different forms may be used as shown in

Figure 4. Where more than one rotor 14 is used, they may be

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separated from one another by partition walls 2 9 in the housing 12.

In any event, the number, orientation and form of the 5 turbine(s) used in each device 10 is chosen to maximise the performance of the device 10.

In use, a number of power generating devices 10 are located adjacent to each other in an end-to-end relationship to form 10 an array of devices as shown in Figure 5c. In this configuration, the protruding male connections 30 engage with the corresponding female connections 32 and the base 18 of each device 10 is in electrical contact with the base 18 of each adjacent device 10.

15

Figures 6a and 6b show a conventional pitched roof 44 formed by a plurality of flat tiles 46 and a series of ridge tiles 4 8 along its apex.

20 In one embodiment of the present invention, the linear array of devices 10 may be located along the top beam of the roof of a house as shown in Figures 7a and 7b. Each power generating device 10 is designed to be fixed to the beam using mortar or the like. However, other fixing methods may 25 equally be used. The roof 28 of the housing 12 is shaped to match the underside of a standard ridge tile 48. A layer of mortar can be applied to the upper surface of the housing roof 28 upon which a standard ridge tile 48 can be placed and bedded in.

30

It would also be possible to omit the standard ridge tile 48 and have small solar panels on the pitched roof 28 of the

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housing 12, wired into the conductive path so as to add their own generated electricity to that provided by the rotor 14 and generator 16.

5 A roof of a house thus constructed with an array of power generating devices 10 contains a gap 50 between the upper surface of the standard roof tiles 46 and the underside of the overhanging roof 28 of the housing 12.

10 When wind passes over the roof of a house a pressure i

difference is set up between the high pressure windward side of the roof and the low pressure leeward side of the roof. This pressure difference causes air to be forced through the open side of the housing 12 located on the windward side of 15 the roof and out through the other open side on the leeward side of the roof. Due to the overhang of the housing roof 28, a wind tunnel effect is created in the gap 50 which promotes airflow through the housing 12. As the air passes through the gap 50 a force is applied to the surfaces 38 and 20 40 of the rotor blades 36 causing the spindle 34 to rotate. This in turn causes the generator 16 to operate and produce an electric current.

V-.

The electricity generated passes from the electric generator 25 16 to the electrically conductive path provided in the base 18 of the power generating device 10.

In use the electrical current generated by each device 10 passes along the conductive path provided by the array of 30 devices 10 to a terminating block 52 shown in Figure 8. The terminating block 52 comprises a substantially rectangular housing with a pitched roof so as to match the configuration

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of the devices 10, although it is shorter in length. The terminating block 52 is then wired directly by suitable cabling 53 into a power control apparatus, which is preferably a type of Uninterrupted Power Supply (UPS) 54 5 which will either store the electrical energy, supply power to the building or return power to an external source, typically the national grid. Using a UPS also helps to avoid spiking or surges in electrical current.

A type of UPS device 54 is shown in Figure 9. The UPS device 54 comprises a rectifier 56 which converts alternating current (AC) into direct current (DC), a battery bank 58 for storing the energy generated from the array of power generating devices 10, an inverter 60 for converting DC to AC, an isolation maintenance switch 62 for isolating the upstream components during maintenance, an intelligent electric switch 64 which determines whether energy is stored or delivered to either the building's electric circuit or to the grid, and a power central node 66 for channelling energy to either the building's electric circuit or to the grid.

In use, the electrical energy generated from the array of power generating devices 10 is delivered as an alternating current.' In one mode of operation the alternating current 25 passes through the rectifier 56 where it is converted into a direct current which is used to charge the battery bank 58. Any additional electricity generated from solar panels positioned on the roof of the building in place of ridge tiles 48 will pass directly to the battery bank 58 as a 30 direct current. When required, the energy stored in the battery bank 58 is drawn as a direct current and passes through the inverter 60 where it is converted into an AC

10

15

20

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output for use by either the first or second user. In a second mode of operation, the alternating current supplied from the power generating devices 10 is delivered directly to the inverter 60 to supply AC output on demand.

5

If the combination of energy stored in the batteries 5 8 of the UPS device 54 and the energy supplied from the array of power generating devices 10 is sufficient to meet the building's energy requirements at any one time, the UPS 54 10 will deliver the required energy on demand. If the UPS 54

is unable to supply sufficient energy to meet the building's energy requirements it automatically and instantaneously switches such that the energy requirement is entirely met by supply from the grid, until such time as energy from the 15 array and/or battery bank 58 is sufficient, at which point the UPS device 54 will switch back. If the battery pack 58 contained within the UPS 54 is fully charged and the energy provided by the array of devices 10 is more than meeting the building's energy requirement, then the excess energy is 20 supplied back to the grid.

In this way, while the output from each power generating device,'10 is small, the array of devices 10 along a roof is capable of producing a much greater cumulative output which 25 is of useful size. The combination of the array of devices 10 with the power control apparatus provided by the UPS 54 ensures that the building's energy needs are always met and that the power generated by the array is utilised to best effect and not wasted if there is no demand from the 30 building itself. Furthermore, the small scale nature of each device 10 and the highly efficient design of the blades 36 will maximise the functionality of the apparatus. Even

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on a still day, airflow over the ridge of a typical house roof can be some seven times greater than at ground level and the present invention is designed to take advantage of any airflow, however small. Additionally, this is achieved 5 with virtually no visual or audible impact on the environment, obviating any objections on those grounds.

For a domestic application, the UPS device 54 is typically about the size of other household white goods such a fridge 10 or tumble dryer. The batteries 56 may be conventional high-powered sealed batteries similar to truck batteries. Using such relatively crude high-powered batteries will enable the UPS device 54 to supply more power for longer than conventional UPS devices. The batteries will preferably be 15 sufficient to meet typical domestic demand for 6 hours or more, covering the peak morning and evening usage and allowing the batteries to recharge overnight or during the day when the residents are out.

20 The UPS device 54 may be contained in its own housing,

openable to allow maintenance etc., and sized to fit into any convenient location such as existing cupboard space in a kitcheii or utility room and so on.

i -

25 The modular nature of the apparatus means that it is easily adaptable to different sizes of building, from typical domestic dwellings to larger business/industrial premises or blocks of flats. It will be appreciated that although described with reference to a pitched roof for positioning 30 beneath ridge tiles, the shape of the housing 12 may be altered as appropriate to the location of installation.

Thus, the apparatus could be incorporated within the top of

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a perimeter wall around a flat office block roof for example.

Furthermore, it is envisaged that suitably configured, and 5 further miniaturised, power generation devices of the present invention could be incorporated into other structures such as land vehicles, seacraft or aircraft. For example, an array of miniature power generation devices could be incorporated into a roof panel of a car, an 10 aircraft fuselage or the hull or mast of a ship.

Accordingly, the present invention provides apparatus for generating "clean" energy without the pollution inherent in traditional fossil fuel or nuclear power generation systems. 15 The apparatus is easily scalable to suit different applications and avoids the negative visual and audible environment impact of traditional wind-energy systems. As the skilled reader will appreciate a number of variations, modifications and alterations could be implemented and the 20 precise details of the embodiments described may be altered without departing from the scope of the claims.

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Claims

1. An electricity generating device comprising a hollow housing, a plurality of openings defined in walls of the

5 housing and shaped to promote fluid flow through the housing, at least one rotor rotatably mounted in the housing and connected to a generator in the housing which is operable to generate electricity in response to rotation of the rotor caused by fluid flow through the housing, and 10 interconnection means for physically and electrically i

connecting the device to one or more like devices.

2. An electricity generating device as claimed in claim 1, wherein the at least one rotor comprises a spindle and a

15 plurality of flow-capture surfaces configured to cause rotation of the spindle when acted upon by fluid flow from any of plurality of different directions.

3. An electricity generating device as claimed in claim 1 20 or claim 2, comprising a plurality of rotors.

4. An electricity generating device as claimed in claim 3, wherein at least two of the plurality of rotors are configured and/or oriented differently from each other.

25

5. An electricity generating device as claimed in any preceding claim, wherein the housing comprises a substantially rectangular box with a pitched roof dimensioned so as to be locatable at the apex of a pitched

30 roof of the building, beneath a ridge tile.

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6. An electricity generating device as claimed in claim 5, wherein the openings are formed in opposing side walls of the housing and the pitched roof of the housing overhangs the openings.

5

7. An electricity generating device as claimed in any preceding claim, wherein the interconnection means comprises a projection extending from one wall of the housing and a corresponding recess defined in an opposing wall of the

10 housing.

8. An electricity generating device as claimed in any preceding claim, wherein the interconnection means comprises an electrically conductive path provided in the base of the

15 housing.

9. A modular electricity generating apparatus comprising a plurality of electricity generating devices as claimed in any preceding claim interconnected to form an array, and

20 means to connect the array to a power control device wherein the power control device comprises means to store electrical energy generated by the array and means to selectively supply; electricity to a first user or a second user.

25 10. A modular electricity generating apparatus as claimed in claim 9, wherein the power control device comprises an uninterrupted power supply device operable to supply electricity to a first user in response to demand therefrom utilising electricity generated by the array when sufficient

30 is available from the array, or otherwise utilising electricity supplied by the second user.

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11. A modular electricity generating apparatus as claimed in claim 10, wherein the uninterrupted power supply device is operable to supply electricity back to the second user if the quantity of electricity generated by the array exceeds

5 the demand of the first user.

12. A modular electricity generating apparatus as claimed in any preceding claim, wherein the first user comprises the electrical system of a structure to which the array is

10 connected and the second user consists of an external electricity supply such as the national grid.

13. An electricity generating device substantially as hereinbefore described and with reference to the

15 accompanying drawings.

14. A modular electricity generating apparatus substantially as hereinbefore described and with reference to the accompanying drawings.

20

769838, SWM, SWM

Amended claims have been filed as follows.

n

1. An electricity generating device comprising a hollow housing, a plurality of openings defined in walls of the 5 housing, at least one rotor rotatably mounted in the housing and connected to a generator in the housing which is operable to generate electricity in response to rotation of the rotor caused by air flow through the housing, and interconnection means for physically and electrically 10 connecting the device to one or more like devices, wherein the housing comprises a substantially rectangular box with a pitched roof, dimensioned so as to be locatable at the apex of a pitched roof of a building, beneath a ridge tile, and wherein the openings are formed in opposing side walls of 15 the housing and the pitched roof of the housing overhangs the openings, such that, in use, the pitched roof is substantially parallel to the plane of the pitched roof of the building creating a gap which promotes airflow through the housing.

2. An electricity generating device as claimed in claim 1, wherein the at least one rotor comprises a spindle and a plurality of flow-capture surfaces configured to cause rotation of the spindle when acted upon by fluid flow from

25 any of plurality of different directions.

3. An electricity generating device as claimed in claim 1 or claim 2, comprising a plurality of rotors.

30

&

4. An electricity generating device as claimed in claim 3, wherein some of the plurality of rotors are mounted substantially horizontally in use and others are mounted substantially vertically in use.

5

5. An electricity generating device as claimed in any preceding claim, wherein the interconnection means comprises a projection extending from one wall of the housing and a corresponding recess defined in an opposing wall of the

10 housing.

6. An electricity generating device as claimed in any preceding claim, wherein the housing includes a base and the interconnection means comprises an electrically conductive 15 path provided in the base of the housing.

• •• • ► « • •• •

7. A modular electricity generating apparatus comprising a plurality of electricity generating devices as claimed in any preceding claim interconnected to form an array, and 20 means to connect the array to a power control device wherein the power control device comprises means to store electrical energy generated by the array and means to selectively supply electricity to a first user or a second user.

25 8. A modular electricity generating apparatus as claimed in claim 7, wherein the power control device comprises an uninterrupted power supply device operable to supply electricity to a first user in response to demand therefrom utilising electricity generated by the array when sufficient 30 is available from the array, or otherwise utilising electricity supplied by the second user.

9. A modular electricity generating apparatus as claimed in claim 8, wherein the uninterrupted power supply device is operable to supply electricity back to the second user if the quantity of electricity generated by the array exceeds

5 the demand of the first user.

10. A modular electricity generating apparatus as claimed in any preceding claim, wherein the first user comprises the electrical system of a structure to which the array is

10 connected and the second user consists of an external electricity supply.

11. An electricity generating device substantially as hereinbefore described and with reference to Figures 1 to 5

15 and 7 to 9.

12. A modular electricity generating apparatus

, substantially as hereinbefore described and with reference

• to Figures 1 to 5 and 7 to 9.

20