WO2020061651A1

WO2020061651A1 - Electricity supply controller system

Info

Publication number: WO2020061651A1
Application number: PCT/AU2019/051057
Authority: WO
Inventors: Scott Allen Graham
Original assignee: Graham Enterprises Holdings Pty Ltd
Priority date: 2018-09-28
Filing date: 2019-09-30
Publication date: 2020-04-02

Abstract

An electricity supply controller circuit configured to be connected between a solar power supply comprising an inverter connected to a photovoltaic array generating solar power and an electrical distribution board connected to a mains power supply providing mains power to a plurality of electrical loads. The electricity supply controller is adapted to isolate at least one of the plurality of electrical loads from receiving mains power from the mains power supply and solar power from the inverter in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

Description

Electricity Supply Controller System

TECHNICAL FIELD

[001] The present invention relates to an electricity supply controller and an electricity supply controller system for distributing and metering the supply of electricity to multiple tenants (including both residential and commercial tenants) from multiple onsite renewable generation sources such as a local solar supply or other renewable energy generation methods.

BACKGROUND

[002] Any references to methods, apparatus or documents of the prior art are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge.

[003] With the rise in interest in reducing carbon emissions and rising electricity costs, many tenants are looking to how renewable energy generation systems can be used in their own homes or businesses. One very popular form of renewable energy is the use of photovoltaic arrays (i.e. solar panels) which can typically be placed on a roof of a dwelling to capture light and generate electricity. However, existing systems primarily rely on a single set of solar panels for each residence, which therefore requires an inverter system for each residence. This is an inefficient use of resources and can be unsightly in housing communities having large numbers of apartments or townhouses in close proximity to each other.

[004] In addition, as multilevel apartment dwellings or commercial sites (often having hundreds of residences) become more popular for inner-city living, it is infeasible for every apartment to have an individual set of solar panels and inverter system and indeed it may be prohibited to do so as the building is typically operated by a body corporate entity which would not allow such installations.

[005] Previous attempts to provide shared solar power to these strata blocks have been highly complex and often do not provide for individual isolation for residences from both solar and mains powers, which is a safety concern.

[006] Furthermore, some existing systems are predicated on an“all or nothing” instalment whereby every residence must agree to opt-in to the solar panel scheme otherwise no system can be installed which is not ideal and prohibits the uptake of solar panels in apartment blocks. It would be advantageous if upon a unit being sold the new owner would have the option of opting in or out to the solar panel electricity scheme.

SUMMARY OF INVENTION

[007] In an aspect, there is provided an electricity supply controller circuit configured to be connected between a solar power supply comprising an inverter connected to a photovoltaic array generating solar power and an electrical distribution board connected to a mains power supply providing mains power to a plurality of electrical loads, wherein the electricity supply controller is adapted to isolate at least one of the plurality of electrical loads from receiving mains power from the mains power supply and solar power from the inverter in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

[008] In another aspect, the invention provides a method for controlling electrical power supply to a plurality of tenancies, the method comprising the steps of:

connecting a mains power supply to a plurality of electrical loads respectively located in a plurality of tenancies;

connecting a solar power supply to the plurality of electrical loads;

providing mains power to the plurality of electrical loads from the mains power supply while solar power is not available from the solar power supply;

providing solar power to the plurality of electrical loads from the solar power supply while solar power is available from the solar power supply; and

isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply and solar power from the solar power supply in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

[009] Preferably, the method further comprises the step of isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply such that no power is supplied to the at least one of the plurality of electrical loads.

[010] Preferably, the method further comprises the step of individually isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply. [011] Preferably, the method further comprises the step of individually isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply independently of each of the plurality of electrical loads.

[012] In another aspect, the invention provides a system for controlling electrical power supply to a plurality of tenancies comprising:

a solar power supply comprising:

a photovoltaic array for generating DC power from sunlight; and an inverter connected to the photovoltaic array for converting DC power generated by the photovoltaic array into AC solar power;

a distribution board connected to a mains power supply providing mains powers and a plurality of electrical loads respectively located in a plurality of tenancies; and

an electricity supply controller circuit electrically connecting the solar power supply and the distribution board, wherein the electricity supply controller circuit is adapted to isolate at least one of the plurality electrical loads from receiving power from the solar power supply in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

[013] Preferably, the system is further adapted to isolate at least one of the electrical loads from receiving power from the mains power supply.

[014] Preferably, the system is further adapted to individually or independently isolate at least one of the plurality of electrical loads from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being individually electrically disconnected from the mains power supply.

[015] Preferably, the system is further adapted to individually isolate at least one of the plurality of electrical loads from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being individually electrically disconnected from the mains power supply independently of each of the plurality of electrical loads.

[016] Preferably, the electricity supply controller circuit comprises one or more solar electricity meters for monitoring and recording an amount of solar power provided to each electrical load of the plurality of electrical loads from the solar power supply. Preferably, the distribution board comprises one or more mains power electricity meters for monitoring and recording an amount of electricity provided to each electrical load of the plurality of electrical loads from the mains power supply. The use of the two meters allows the use of the mains power and the use of the solar power to be monitored and monitored separately. Preferably, the main power electricity meter is an import/export meter or a bi-directional meter.

[017] Preferably, the electricity supply controller circuit comprises at least one normally open contactor for isolating at least one of the plurality of electrical loads from the solar power supply, wherein each normally open contactor is configured to open (or remain de-energised) in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

[018] Preferably, the electricity supply controller circuit the electricity supply controller circuit comprises at least one main circuit breaker or one main isolator connected to each of the plurality of electrical loads for isolating each of the plurality of electrical loads from the mains power supply and connected to one of the at least one normally open contactors, wherein each electrical load of the plurality of electrical loads can be isolated individually and independently of every other electrical load of the plurality of electrical loads from both mains power and solar power by switching off the main circuit breaker or main isolator of the electrical load which causes the normally open contactor to open (or de-energise).

[019] Preferably, the electricity supply controller circuit is located in an IP rated cabinet adjacent the distribution board.

[020] Preferably, the main circuit breaker or main isolator connected to the load of the residence is a two-pole circuit breaker or a two-pole isolator. Preferably, a line side of a first pole of the main circuit breaker or main isolator is connected to the mains power. Preferably, a line side of a second pole of the main circuit breaker or main isolator comprises a mains power loop, wherein a load side of the first pole is connected to the line side of the second pole. Preferably, a load side of the second pole is connected to a second circuit breaker to protect the cables by a control cable wired to a relay that controls the line side of the normally open contactor of the electricity solar supply controller circuit. Alternatively, a load side of the second pole is connected to a second circuit breaker to protect the cables by a control cable wired to a line side of the normally open contactor of the electricity solar supply controller circuit. Preferably, the load side of the normally open contactor is connected to the load side of the first pole of, for example, the main circuit breaker or main isolator. [021] In another aspect, the invention provides a method for controlling electrical power supply to a plurality of tenancies, the method comprising the steps of:

providing mains power to the plurality of electrical loads from a mains power supply while solar power is not available from a solar power supply;

disconnecting at least one of the plurality of electrical loads from the mains power supply and the solar power supply via a first switch connected to the mains power supply synchronised with a second switch connected to the solar power supply, wherein switching the first switch off switches the second switch off.

[022] In another aspect, there is provided a system for controlling electrical power supply to a plurality of tenancies comprising:

a solar power supply comprising:

a distribution board connected to a mains power supply providing mains powers and a plurality of electrical loads respectively located in a plurality of residences; and

an electricity supply controller circuit electrically connecting the inverter and the distribution board, wherein the electricity supply controller comprises a first switch connected to the mains power supply and a second switch connected to the solar power supply, wherein the second switch is synchronised with the first switch, wherein switching the first switch off switches the second switch off, and whereby at least one of the plurality of electrical loads is isolated from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

[023] In an aspect, there is provided an electricity supply controller circuit configured to be connected between a renewable energy power supply generating renewable power and an electrical distribution board connected to a mains power supply providing mains power to a plurality of electrical loads, wherein the electricity supply controller is adapted to isolate at least one of the plurality of electrical loads from receiving mains power from the mains power supply and renewable power from the inverter in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

BRIEF DESCRIPTION OF THE DRAWINGS

[024] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

FIG. 1 is a schematic diagram of a system for controlling electricity supply according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a circuit for controlling electricity supply according to an embodiment of the present invention;

FIG. 2a is a close-up schematic of circuit breaker 240 shown in FIG. 2;

FIG. 3 is a simple circuit diagram of an embodiment of the present invention; FIG. 4 is a schematic diagram of a circuit for controlling electricity supply according to another embodiment of the present invention; and

FIG. 4a is a close-up schematic of circuit breaker 440 shown in FIG. 2.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[025] The present invention relates to a system for generating and distributing renewable power (such as solar power, for example) to a number of tenants, including residential and commercial tenants.

[026] FIG. 1 illustrates a system 10 for generating and distributing solar power to a plurality of residences. The system 10 includes a photovoltaic array 100 having a number of solar panels which convert incident light to generate a Direct Current (DC) electrical current.

[027] The photovoltaic array 100 is connected to an inverter system 110 which converts the DC power generated by the photovoltaic array 100 into three-phase Alternating Current (AC) which can be used by a household to power appliances and fixtures. [028] The inverter system 110 is connected to and feeds the AC power to a solar distribution centre 120 which houses an electricity supply controller circuit 200 (which is more particularly shown in FIG. 2 and 2a).

[029] The electricity supply controller circuit 200 is connected to a typical multi- residence distribution board 130 of a complex of townhouses or residential unit or which houses a main switch 140 (which is described more specifically below) and individual tenant meters 150 which meter mains power consumed by each individual residence. These individual tenant meters 150 are typically import/export type electricity meters or bi-directional electricity meters.

[030] Turning to Figures 2 and 2a, the electricity supply controller circuit 200 includes an AC isolating switch 210 connected to a main switch 220 (typically a 63A switch) which distributes the incoming AC power from the inverter system 110 through a number of distribution circuit breakers 230 (although only one is shown in the present illustration) that are equal to the number of tenancies or residences to be supplied. In use, the AC isolating switch 210 is typically located on an external surface of a distribution board and allows an electrician to instantaneously isolate the electrical supply to every residence without accessing the internal portion of the enclosure that would typically contain electricity supply controller circuit 200.

[031] As mentioned above, each distribution circuit breaker typically corresponds to a residency of the complex and thus the number of circuit breakers is dependent upon the number of residences that the system is servicing.

[032] In the illustrated embodiment, an 18 pole chassis 201 is used that is capable of housing 18 individual single-phase circuit breakers (including distribution circuit breakers 230) or 6 three-phase circuit breakers. Flowever, this number and configuration can be varied based on specific requirements.

[033] The distribution circuit breakers 230 are necessary to allow individual tenancies to all be independently isolated as required (for example, to conduct maintenance or installations). As a result, the residences are all connected to the same photovoltaic array and the residences, collectively, do not need to be electrically disconnected in the event that only one residence requires disconnection to allow work to be carried out.

[034] The distribution board 130a (substantially similar to distribution board 130 of Figure 1 ) includes a circuit breaker 240 (which is also substantially similar to main switch 140 described above) connected to each tenant meter panel 150. The circuit breaker 240 is either a two-pole circuit breaker (as shown in FIG. 2) or a four pole circuit breaker for a three phase connection.

[035] The wiring configuration of the two-pole circuit breaker 230 will now be described in more detail. An enhanced view of the circuit breaker 230 can be seen in Figure 2a.

[036] In practice, the line side of pole B 240b of the circuit breaker 240 serves as a connection to grid/mains power 260. A control wire 252 is connected to the load side of pole B 240b and extends to the line side of pole A 240a of the circuit breaker 240. The load side of pole A 240a of the circuit breaker 240 is connected to the line side of the control circuit breaker 270 by control wire 251.

[037] The load side of the control circuit breaker 270 connects to a control relay 275 (which may take the form of a mechanical control relay such as a coil or a smart or solid state relay). The control relay 275 is also connected to the main switch 220 through relay circuit breaker 276 and control wire 253 extending from control relay 275 to relay circuit breaker 276.

[038] The control relay 275 controls the state of a contactor 250 which is connected at one end to the solar electricity meter 280 and at the other end to the load side of pole B 240b of the circuit breaker 240. The solar electricity meter 280, connected between the contactor 250 and the distribution circuit breaker 230, records the amount of electricity supplied from the photovoltaic array 100 and inverter system 110 to a residence individually from any other residences also receiving electricity from the solar system. This meter can be any type of meter suitable for recording the consumption of electricity. Flowever, in some embodiments, the meter is a smart meter having a modem and wireless data transmission system to eliminate the need for human meter readers to physically attend to the meter and record the readings for each meter.

[039] In use, when a voltage in excess of approximately 60% of 240V (i.e. 145V) is detected by the control relay 275 from control wire 251 , the control relay 275 sends a signal through control wire 254 to energise the contactor 250 and thereby change the state of the contactor 250, which is normally open, to be“closed”. In the“closed” position, solar power is able to flow through the contactor 250 to the load side of pole B 240b of the circuit breaker 240 and thus provide power to the distribution board 285. [040] In the instance that both mains power and solar power must be disconnected from a residence (for example to allow electrical maintenance to be carried out on a particular residence), the circuit breaker 240 is changed to an“off” or open position (i.e. no power is flowing). Typically, solar power would continue to be able to flow to the residence in the absence of mains power. However, in the present embodiment of the invention, when the circuit breaker 240 is open, the control relay 275, via control wire 251 , detects a lack of voltage and closes the output from the control relay 275 to the contactor 250 to de-energise the contactor 250 and ensure the contactor 250 remains in an“open” state and thereby prevent solar power from being supplied to the circuit breaker 240 and residence distribution board 285. This ensures that no power (either from the grid or the solar array) is provided when the circuit breaker 240 is open or switched off, thereby ensuring the safety of any maintenance workers.

[041] When the circuit breaker 240 is returned to a“closed” state, the control relay 275, once again through control wire 251 , detects the presence of a voltage at the load side of pole A of circuit breaker 240a and re-opens the output of the control relay 275 to allow power to be supplied to the residence distribution from the grid, the solar power system, or both, as appropriate.

[042] Turning to FIG. 3, there is shown an embodiment of an electricity supply controller connected to two residences. Similar to the embodiments described above, the present embodiment includes a photovoltaic array 300 connected to an inverter system 305 for converting the DC power generated by the array into AC power for consumption by the loads of the residences 301 a, 301 b.

[043] The inverter 305 is connected to a main switch 310 having two circuit breakers 310a, 310b (one for each residence 301 a, 301 b, respectively). The main switch 310 also includes a relay circuit breaker 310c connected to a control relay 302a, 302b through control wire 303 for each residence 301a, 301 b. The operation of the control relays 302a, 302b will be further described below.

[044] The connection for each residence 301 a, 301 b includes an electricity meter 315a, 315b connected between the main switch 310 and normally open contactors 320a, 320b. The electricity meters 315a, 315b record the consumption of solar power in the system for each residence 301 a, 301 b. Each residence 301 a, 301 b is individually metered 315a-d for both mains power 300b and solar power, as indicated by“METER 1”,“METER 1 S”,“METER 18” and“METER 18S”. [045] The states of the normally open contactors 320a, 320b mentioned above are controlled from the existing residence meter panel 325 via control wires 31 1a, 311 b from circuit breakers 330a, 330b and the control relays 302a, 302b.

[046] Moving to the circuit breaker 330a, 330b located in the residence meter panel 325 (which is a two pole circuit breaker for the purposes of this invention), the line side of pole B of each circuit breaker 330a, 330b is connected to mains power 300b (also known as grid power).

[047] A control wire 312a, 312b is also connected to the load side of pole B of each circuit breaker 330a, 330b and extends to the line side of pole A of each respective circuit breaker 330a, 330b. The load side of pole A of each circuit breaker 330a, 330b is connected to the control relay 302a, 302b. Additional circuit breakers may be used to protect the cables.

[048] In use, when solar power is available (for example, during the day), and the circuit breakers 330a, 300b are closed or on, the control relays 302a, 302b, detect that a voltage is present through control wires 31 1a, 311 b respectively connected to the load side of pole A of circuit breakers 330a, 330b. In response, the control relays 302a, 302b generate and transmit signals to energise the respective normally open contactors 320a, 320b and switch the contactors 320a, 320b to a“closed” or“on” state, thereby allowing solar power to be received at the loads of the residences 301 a, 301 b. Importantly, the contactors 320a, 320b remain closed at all times while normal supply is available at the load side of pole A of circuit breakers 330a, 330b. If power is available from the inverter 305, that power will be supplied to the loads 1 , 18 at residences 301 a, 301 b.

[049] In an example, if electrical work is required at residence 301a but not residence 301 b, circuit breaker 330a on the residence meter panel 325 is manually changed to the“off” or“open” position while circuit breaker 330b remains in the “closed” or“on” position. When circuit breaker 330a is opened, the control relay 302a connected to pole A of circuit breaker 330a through control wire 311 a detects that no voltage is present at the load side of pole A of circuit breaker 330a. Consequently, the control relay 302a de-energizes the contactor 320a thereby changing the contactor 320a to an open state, even if solar power is presently available. As a result, residence 301 b can continue to receive power, from both the grid 300b and solar array 300, while maintenance is conducted on residence 301 a. [050] Ultimately, the normally open contactors 320a, 320b allow the mains power and solar power to be simultaneously disconnected from a single residence as required, while also allowing other residences to continue receiving power uninterrupted.

[051] The above configuration and the normally open contactor for each residence’s solar feed provide each residence with a single point of electrical isolation from solar.

[052] In essence, the circuit breaker for each residence allows instantaneous electrical isolation from both the mains powers from the grid and solar power from the photovoltaic array.

[053] In use, mains power flows regularly from the mains power supply 300b to a main switch having a double pole circuit breaker 310a, 310b for the respective residences 301 a, 301 b.

[054] During the day, the photovoltaic array 300 will produce DC power that is converted in AC power by the inverter 305.

[055] Electrical isolation of individual residences from both the mains power and the solar power is important from a safety consideration and is often necessary to comply with local, state or federal building code requirements (in Australia, for example).

[056] In some embodiments, a battery storage system is provided to store excess power generated by the photovoltaic array during the day which is often when most photovoltaic arrays are at maximum electricity production but residential usage is low.

[057] In embodiments where electricity is being provided in a single phase to a residence, each residence is individually metered for consumption of solar power by an electricity meter located within the solar distribution centre. In some alternative embodiments, electricity can be provided in three-phase.

[058] Turning to Figures 4 and 4a, there is shown an electricity supply controller circuit 400. Electricity supply controller circuit 400 is similar to electricity supply controller circuit 200 described above and can be provided in place of electricity supply controller circuit 200, for example in system 10. As described in relation to system 10 above, electricity supply controller circuit 400 is connected to a typical multi-residence distribution board 130 of a complex of townhouses or residential unit or which houses a main switch 140 (which is described more specifically below) and individual tenant meters 150 which meter mains power consumed by each individual residence. These individual tenant meters 150 are typically import/export type electricity meters or bi-directional electricity meters.

[059] The electricity supply controller circuit 400 includes an AC isolating switch 410 connected to a main switch 420 which distributes the incoming AC power through a number of circuit breakers 430. The AC isolating switch 410 is typically located on an external surface of a distribution board and allows an electrician to instantaneously isolate the electrical supply to every residence.

[060] In the illustrated embodiment there is only one connection shown. However, it should be understood that up to 18 connections could be provided in the illustrated embodiment by replicating the wiring described herein and shown in the figures.

[061] Each circuit breaker typically corresponds to a residency of the complex and thus the number of circuit breakers is dependent upon the number of residences that the system is servicing.

[062] In the illustrated embodiment, an array of 18 individual single-phase circuit breakers 430 is provided. In some alternative embodiments, an array of 6 three- phase circuit breakers is used. However, this number can be varied based on specific requirements.

[063] The circuit breakers 430 are necessary to allow individual tenancies to all be isolated as required (for example, to conduct maintenance or installations). As a result, the residences are all connected to the same photovoltaic array and the residences, collectively, do not need to be electrically disconnected in the event that only one residence requires disconnection to allow work to be carried out.

[064] The distribution board 130b (which is substantially the same distribution board 130 described above) includes a circuit breaker 440 (which is also the same as circuit breaker 240 described above) connected to each tenant meter panel 150. The circuit breaker 440 is either a two-pole circuit breaker (as shown in FIG. 2) or a four- pole circuit breaker for a three-phase connection. The line side of pole B 440b of the circuit breaker 440 serves as a connection to grid/mains power 460. A control wire 452 is connected to the load side of pole B 440b and extends to the line side of pole A 440a of the circuit breaker 440. The load side of pole A 440a of the circuit breaker 440 is connected to the line side of the control circuit breaker 470 by control wire 451.

[065] The load side of the control circuit breaker 470 connects to contactor 450 (through control wire 454) which is connected at one end to the solar electricity meter 480 and at the other end to the load side of pole B 440b of the circuit breaker 440. The solar electricity meter 480, connected between the contactor 450 and the distribution circuit breaker 430, records the amount of electricity supplied from a solar power system (such as photovoltaic array 100 and inverter system 110, for example) to a residence individually from any other residences also receiving electricity from the solar power system. This meter can be any type of meter suitable for recording the consumption of electricity. However, in some embodiments, the meter is a smart meter having a modem and wireless data transmission system to eliminate the need for human meter readers to physically attend to the meter and record the readings for each meter.

[066] In use, when a voltage is present along control wire 454 (bridging control circuit breaker 470 and contactor 450) which is connected to control wire 451 via control circuit breaker 470, the contactor 450 is energised and closes (from a normally open state) and thereby change the states of the normally open contactor 450 to be“closed”. In the“closed” position, assuming power is being supplied by the solar array, due to the higher voltage of the solar supplied power compared to the mains power, solar power is able to flow through the contactor 450 (from wire 453 coming from distribution circuit breaker 430 via the meter 480) to the load side of pole B 440b of the circuit breaker 440 and thus provide power to the residence distribution board 485. In the absence of any solar power, contactor 450 remains energised but mains power from the grid flows through pole B 440b of the circuit breaker 440 to the residence distribution board 485.

[067] In the instance that both mains power and solar power must be disconnected from a residence (for example to allow electrical maintenance to be carried out on a particular residence), the circuit breaker 440 is changed to an“off” or open position (i.e. no power is flowing). Typically, solar power would continue to be able to flow to the residence in the absence of mains power. However, in the present embodiment of the invention, when the circuit breaker 440 is open, the contactor 450, via control wire 454 which bridges control circuit breaker 470 and contactor 450, detects a lack of voltage at the load side of pole A of circuit breaker 440a and the contactor 450 is de-energised. This ensures that contactor 450 remains in an “open” state and thereby prevents solar power from being supplied to the residence distribution board 485 when circuit breaker 440 is switched off and grid/mains power is disconnected from the residence. [068] When the circuit breaker 440 is returned to a“closed” state, the contactor 450 detects the presence of a voltage from the grid via control wire 454 and is energised and thus changes to a“closed state” to allow power flow from the grid, and solar array and inverter system.

[069] The invention described herein provides a single solar system and a single inverter to provide electricity to multiple residences. As a result, this can reduce infrastructure costs and maintenance costs.

[070] Furthermore, embodiments of the invention allow the electricity consumption of solar power from each residence to be individually metered and this information can be wirelessly transmitted to an energy retailer.

[071] The invention maintains a single isolation point for electrical work purposes on tenancies without disrupting solar power feed to remaining tenancies.

[072] The IP (ingress protection) rating of the enclosure is such that it can be mounted on an external or internal surface of a building. For example, if the enclosure is in a switch room the enclosure may only require an IP40 rating. Alternatively, if the enclosure is on the outside of a building an IP5 rating may be necessary.

[073] In some further embodiments, the enclosure has an outer door and an internal escutcheon that is IP4X rated. The internal main switch and the residences solar circuit breakers and the meters can be safely accessed, with no live parts exposed. Behind the escutcheon is access by qualified electricians only and can only be opened by use of a tool or key as per AS3000 2018. The layout of components behind the escutcheon allow for easy access to components for the control and power wiring to be performed, in the factory and on site.

[074] In this specification, adjectives such as first and second, left and right, top and bottom, and the like may be used solely to distinguish one element or action from another element or action without necessarily requiring or implying any actual such relationship or order. Where the context permits, reference to an integer or a component or step (or the like) is not to be interpreted as being limited to only one of that integer, component, or step, but rather could be one or more of that integer, component, or step, etc.

[075] The above detailed description of various embodiments of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art of the above teaching. Accordingly, while some alternative embodiments have been discussed specifically, other embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. The invention is intended to embrace all alternatives, modifications, and variations of the present invention that have been discussed herein, and other embodiments that fall within the spirit and scope of the above described invention.

[076] In this specification, the terms‘comprises’,‘comprising’,‘includes’,‘including’, or similar terms are intended to mean a non-exclusive inclusion, such that a method, system or apparatus that comprises a list of elements does not include those elements solely, but may well include other elements not listed.

[077] Throughout the specification and claims (if present), unless the context requires otherwise, the term“substantially” or“about” will be understood to not be limited to the specific value or range qualified by the terms.

Claims

1. A method for controlling electrical power supply to a plurality of tenancies, the method comprising the steps of:

connecting a solar power supply to the plurality of electrical loads;

2. A method in accordance with claim 1 , wherein the step of isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply and solar power from the solar power supply comprises individually isolating the at least one of the plurality of electrical loads from receiving mains power from the mains power supply.

3. A method in accordance with claim 1 , wherein the step of isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply and solar power from the solar power supply comprises individually isolating at least one of the plurality of electrical loads from receiving mains power from the mains power supply independently of each of the plurality of electrical loads.

4. A system for controlling electrical power supply to a plurality of tenancies comprising:

a solar power supply comprising:

a photovoltaic array for generating DC power from sunlight; and an inverter connected to the photovoltaic array for converting DC power generated by the photovoltaic array into AC solar power; a distribution board connected to a mains power supply providing mains powers and a plurality of electrical loads respectively located in a plurality of tenancies; and

an electricity supply controller circuit electrically connecting the solar power supply and the distribution board, wherein the electricity supply controller circuit is adapted to isolate at least one of the plurality electrical loads from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

5. A system in accordance with claim 4, wherein the system is further adapted to individually isolate at least one of the plurality of electrical loads from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being individually electrically disconnected from the mains power supply.

6. A system in accordance with claim 4, wherein the system is further adapted to individually isolate at least one of the plurality of electrical loads from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being individually electrically disconnected from the mains power supply independently of each of the plurality of electrical loads.

7. A system in accordance with any one of claims 4-6, wherein the electricity supply controller circuit comprises one or more solar electricity meters for monitoring and recording an amount of solar power provided to each electrical load of the plurality of electrical loads from the solar power supply.

8. A system in accordance with claim 7, wherein the distribution board comprises one or more mains power electricity meter for monitoring and recording an amount of electricity provided to each electrical load of the plurality of electrical loads from mains power.

9. A system in accordance with claim 8, wherein each of the one or more mains power electricity meters is an import/export meter or a bi-directional meter.

10. A system in accordance with any one of claims 4-9, wherein the electricity supply controller circuit comprises at least one normally open contactor for isolating at least one of the plurality of electrical loads from the solar power supply, wherein each normally open contactor is configured to open in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

11. A system in accordance with claim 10, wherein the electricity supply controller circuit comprises at least one main circuit breaker connected to each of the plurality of electrical loads for isolating each of the plurality of electrical loads from the mains power supply and connected to one of the at least one normally open contactors, wherein each electrical load of the plurality of electrical loads can be isolated individually and independently of every other electrical load of the plurality of electrical loads from both mains power and solar power by switching off the main circuit breaker of the electrical load which causes the normally open contactor to open.

12. A system in accordance with any one of claims 4-11 , wherein the electricity supply controller circuit is located in an Ingress Protection (IP) rated cabinet adjacent the distribution board.

13. A system in accordance with claim 11 , wherein the main circuit breaker is a two-pole circuit breaker.

14. A system in accordance with claim 13, wherein a line side of a first pole of the two-pole circuit breaker is connected to the mains power supply and a load side of the first pole of the two-pole circuit breaker is connected to one of the plurality of electrical loads.

15. A system in accordance with claim 14, wherein a line side of a second pole of the two-pole circuit breaker comprises a mains power loop, and wherein the load side of the first pole of the two-pole circuit breaker is connected to the line side of the second pole of the two-pole circuit breaker.

16. A system in accordance with claim 15, wherein a load side of the second pole of the two-pole circuit breaker is connected to a second circuit breaker by a control cable connected to a relay that controls the normally open contactor of the electricity solar supply controller circuit.

17. A system in accordance with claim 15, wherein a load side of the second pole of the two-pole circuit breaker is connected to a second circuit breaker by a control cable connected to the normally open contactor of the electricity solar supply controller circuit.

18. A system in accordance with claim 16 or claim 17, wherein a load side of the normally open contactor is connected to the load side of the first pole of the two-pole circuit breaker and a line side of the normally open contactor is connected to the solar power supply.

19. A method for controlling electrical power supply to a plurality of tenancies, the method comprising the steps of:

20. A system for controlling electrical power supply to a plurality of tenancies comprising:

a solar power supply comprising:

a distribution board connected to a mains power supply providing mains powers and a plurality of electrical loads respectively located in a plurality of tenancies; and an electricity supply controller circuit electrically connecting the inverter and the distribution board, wherein the electricity supply controller comprises a first switch connected to the mains power supply and a second switch connected to the solar power supply, wherein the second switch is synchronised with the first switch, wherein switching the first switch off switches the second switch off, and whereby at least one of the plurality of electrical loads is isolated from receiving solar power from the solar power supply in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.

21. An electricity supply controller circuit configured to be connected between a solar power supply comprising an inverter connected to a photovoltaic array generating solar power and an electrical distribution board connected to a mains power supply providing mains power to a plurality of electrical loads, wherein the electricity supply controller is adapted to isolate at least one of the plurality of electrical loads from receiving mains power from the mains power supply and solar power from the inverter in response to the at least one of the plurality of electrical loads being electrically disconnected from the mains power supply.