Device for providing information on electricity used at a dwelling and produced by an associated solar panel system

Abstract

A device 10 comprising a first meter 14 and a second meter 15. The first meter measures electricity produced by a solar panel system 24 associated with a dwelling and for causing sending of the first

Description

The invention relates to a device, locatable at a dwelling, for providing information indicative of electricity used by the dwelling and of electricity production by a solar panel system associated with the dwelling. Background One or more people often live in a dwelling without the owner of the dwelling living there. Typically, people living in the dwelling pay for electricity used within the dwelling. Where the dwelling has solar panels (also known as photovoltaic panels), typically the people living in the dwelling benefit from the electricity generated by the solar panels such that the electricity that the dwelling draws from the grid is reduced. Further, those people may benefit from the cost of the electricity drawn from the grid being offset by sale of electricity from the solar panels to their electricity provider. The owner of the dwelling does not benefit from the solar panels, since the owner is not able to use the electricity produced by the panels or sell the electricity. The owner may wish to know how much electricity is supplied to the grid, being sold to the electricity provider, by the people living in the dwelling. There is currently no convenient way to obtain this information. A conventional main meter provides data on the net amount of electricity provided by an electricity supplier, drawn from the grid by the dwelling. Summary of the Invention According to a first aspect of the present invention, there is provided a device comprising: a first meter for measuring electricity produced by a solar panel system associated with a dwelling and for causing sending of the first information; and a second meter for measuring electricity consumed at the dwelling and for causing sending of the second information. The first and second meters may be configured to receive requests (e.g. polling requests) for the first and / or second information from a communications means, wherein the sending of the first information by the first meter is caused in response to the receiving of a request for the first information by the first meter, and the sending of the second information by the second meter is caused in response to the receiving of a request for the second information by the second meter. The first meter may be connected to an output of the solar panel system (or invertor) for measuring the electricity produced by the solar panel system. The second meter may be connected to an input cable to the dwelling for measuring the electricity consumed by the dwelling. The device may be installed in the dwelling in the vicinity of a meeting of a cable for carrying import / export electricity from the grid, a cable for carrying electricity produced by the solar panel system, and the cable for carrying all electricity to be consumed by the dwelling. The device may further comprise connecting means connected to the first and second meters for at least partly enabling the sending of the first and second information. The device may further comprise further comprising a housing that houses at least the first meter, the second meter and the second means. The connecting means may be partially or wholly housed by the housing. The first and second meters may each include a port (for example a RS-485 port), wherein the connecting means comprises at least one cable (for example an RS-485 cable) connecting the ports and for at least partially enabling sending of the first and second information. The connecting means may comprise a gateway unit (e.g. a MODBUS gateway unit) connected to the at least one cable, for receiving the first and second information from the first and second meters, respectively, using a first protocol (e.g. MODBUS), and relaying the first and second information to the communications means using a second protocol, and / or for receiving requests for the first and / or second information from the communications means using the second protocol, and relaying the requests to the first and / or second meters using the first protocol. There may be provided apparatus comprising the device, which may further comprise further connecting means enabling communication between the device and the communication means. The further connecting means may comprise a gateway unit (e.g. a MODBUS gateway unit) connected to the at least one cable, for receiving the first and second information from the first and second meters, respectively, using a first protocol (e.g. MODBUS), and relaying the first and second information to the communications means using a second protocol, and / or for receiving requests for the first and / or second information from the communications means using the second protocol, and relaying the requests to the first and / or second meters using the first protocol. The device of, or the apparatus, wherein the communications means may be configured to send the first and second information to a remote server. The communications means may comprise a communications gateway and / or a communications board of an inverter. The first meter and / or the second meter may be MID-approved and / or revenue grade. According to a second aspect of the present invention, there is provided a method comprising: sending, by a first meter at a device to a communications means, first information indicative of electricity provided by a solar panel system, the solar panel system being associated with a dwelling; sending by a second meter at the device to the communications means second information indicative of electricity consumed by the dwelling. The sending may be in response to a request (e.g. a polling request) from a communications means. The receiving of requests and the sending of the first and second information may be performed periodically. The method may further comprise, sending, by the communications means, the first and second information to a remote server, wherein the server determines third information indicative of electricity provided to a grid using the first and second information. The device may further comprise a housing that houses the first and second meters, and wherein the first and second meters are communicatively coupled to the communications means. The connection means may further comprise a gateway unit (e.g. a MODBUS gateway unit), wherein the unit relays requests from the communications means to the first and second meters and relays responses from the first and second meters to the communications means. The first meter may be connected to an output of the solar panel system (or invertor) for measuring the electricity produced by the solar panel system, wherein the second meter is connected to an input cable to the dwelling for measuring the electricity consumed by the dwelling, wherein the device is installed in the dwelling in the vicinity of a meeting of a cable for carrying import / export electricity from the grid, a cable for carrying electricity produced by the solar panel system, and the cable for carrying all electricity to be consumed by the dwelling. Brief Description of the Figures Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a block diagram of a device in accordance with embodiments, in an environment in which it may be implemented, with arrows indicating electricity flow when the dwelling consumption and the electricity production by the solar panel system are equal; Figure 2 is a block diagram of the device in the environment, with arrows indicating electricity flow when the dwelling consumption is greater than production by the solar panel system; Figure 3 is a block diagram of the device in the environment, with arrows indicating electricity flow when the dwelling consumption is less than production by the solar panel system; Figure 4 is the same block diagram, showing how the consumption and production meters 14, 15 are connected for communication; and Figure 5 is a flow diagram indicating steps in determining of information indicative of electricity supplied by the solar panel system to the grid. Detailed Description of Embodiments Referring to Figures 1 to 3, a device 10 in accordance with embodiments comprises a housing 12, a consumption meter 14, a production meter 15 and a circuit breaker 16. The device 10 is located at a dwelling 20 that has an electrical system for distributing electricity through the dwelling 20. The electrical system within the dwelling 20 is connected to the grid 22, that is, an electricity network for provision of electricity. A main meter 23 is located at an input from the grid 22. The dwelling also has an associated solar panel system 24. A fuse box 21 is located at an input to the dwelling 20 between the dwelling and the grid 22. The dwelling 20 contains various electrical devices and can draw electricity from the grid 22 via the electrical system in a conventional way to power the electrical devices. The power drawn by the electrical devices in the dwelling 20 is the load of the dwelling. The solar panel system 24 includes at least one solar (photovoltaic) panel 26, a communications gateway 28 and an inverter 30 for converting the DC current from the at least one solar panel 26 to AC current. As will be appreciated, there may also be a control system for the inverter 30 and other components, which are not shown. Arrows in Figures 1 to 3 illustrate flow of electricity. The main meter 23 is electrically coupled to a grid connection point, and measures electricity exported / imported to / from the grid 22. Readings of the main meter 23 can be taken locally, typically by a tenant who provides the value to the electricity supplier, or can be send automatically. The value may be a net value for electricity drawn from the grid 22, since some electricity may have been supplied from the solar panels 26. The production meter 15 is electrically coupled to an electricity cable at an output (or electrically equivalent position) of the solar panel system 24 (or inverter 30) to measure electricity produced by the solar panel system 24. The consumption meter 14 is electrically coupled to an input to the dwelling 20 at a load consumption point, and thus is electrically connected to a cable to the dwelling fuse box 21 to measure electricity drawn by the dwelling 20. It is thus electrically connected to both the main meter 23 so that all electricity reaching the dwelling 20 from the grid 22 passes through the consumption meter 14, and to the circuit breaker 16 so that all electricity reaching the dwelling from the inverter 30 passes through the consumption meter 14. The dwelling fuse box 21 may be absent. The circuit breaker 16 may also be absent, in which case the consumption meter 14 is electrically connected to the production meter 15 as well as to the main meter 23. Electricity consumed by the dwelling 20 deriving from the solar panels can be referred to as “self consumption electricity”. Total consumption of the dwelling 20 is calculated as the sum of the self-consumption electricity and the electricity imported from the grid 22. The consumption meter 14 is configured to measure consumption of electricity used by the dwelling 20. The production meter 15 is configured to measure production by the solar panel system 24. As can be understood from Figures 1 to 3, the device 10 is installed at a junction where a cable from the inverter 30, the main meter 23 and the dwelling fuse box 21 meet, so that the consumption meter 14, the production meter and the circuit breaker 16 can all be contained in the housing 12 of the device 10. The communications gateway 28 is for sending of monitoring data to a monitoring platform. The monitoring data comprises at least the production and consumption values. Referring to Figure 4, the device 10 further comprises a connecting means that is part of the device and may be housed or substantially be housed by the housing 12. Further connecting means are also provided that are not necessarily part of the device 10 but that communicatively connect between the device 10 and the gateway 28. In Figure 4, the connecting means and the further connecting means are together in the form of a communications cable 17 connected to the consumption meter 14 and to the production meter 15. The communications may be continuously or in the form of two operatively joined cables (corresponding to connecting means and further connecting means). The cable has a connector element at an end thereof adapted to connect to a corresponding connector element (not shown) at the communications gateway 28. Connections at the consumption meter 14, the production meter 15 and the communications gateway 28 are RS-485 ports, although in variant embodiments they may be alternatively configured. The communications cable 17 is also configured according to the RS-485 specification, although embodiments are not limited to such. In a variant embodiment, the further connecting means is absent and instead the device 10 is configured to enable consumption and production values to be sent to the gateway 28. The connecting means in the form of a cable connects the consumption and production meters 14, 15 to a transceiver module, which communicates with the gateway 28 using a wireless data connection (for example with Zigbee). Alternatively, the connecting means may be in the form of such a communications module for each of the meters 14, 15. The communications gateway 28 is configured to send polling requests via the communications cable 17 or alternative connecting means for consumption values and / or the production values. The relevant one of the consumption meter 14 and the production meter 15 will respond to the request and send the requested value to the gateway 28. The communications gateway 28 is configured to request the consumption and production values periodically, for example every minute. The communications gateway 28 is configured to send the received consumption and production values to a remote server 30 via a communications network 32. Typically, the communications network is the internet and the communications gateway 28 includes a communications module (not shown) configured to connect to a router 32 at the dwelling 20 over Wi-Fi or by an ethernet cable, to enable sending of the consumption and production values to the remote server 30. The communications network 32 may, additionally or alternatively, be a cellular communications network, for example GSM. The server 30 is configured to determine the electricity provided to the grid 22 over a period based on received production and consumption values, particularly corresponding to a start and an end of the period. The consumption meter 14 and the production meter 15 may be any kind of meters capable of metering and providing the values and responding to requests from the communications gateway 28. Preferably, the consumption meter 14 and the production meter 15 are revenue grade meters and / or conform with the European Union’s Measuring Instruments Directive (MID), that is, are MID-approved. The consumption meter 14 and the production meter 15 include a microcontroller and a clock, amongst other components, and the respective microcontroller is configured to store determined values for, respectively, consumption and production, in a memory thereof. The consumption meter 14 and the production meter 15 may each be configured to communicate with a communications gateway 28 in accordance with a predetermined protocol (for example MODBUS), and be configured accordingly to interpret requests and respond in a form interpretable by the communications gateway 28. In a variant embodiment, the further connecting means may comprise a remote terminal unit installed near the device 10. In this case, the unit may include an RS485 port and be connected via the connecting means in the form of a communications cable to the meters 14, 15. The remote terminal unit is configured to send and receive data from the communications gateway 28, typically but not necessarily via a wireless data connection (for example using Zigbee). In a variant embodiment, the remote terminal unit may be integrated with the housing 12 and / or contained within the housing 12, in which case the unit is considered part of the connecting means and further connecting means is the wireless data connection enabled by the unit. Preferably, the remote terminal unit may be configured to communicate with a communications gateway 28 where the communications gateway 28 is one of a number of different gateways that may be provided by different third party suppliers. The unit is configured for communication using different protocols appropriate for the different gateways. In variant embodiments, the microcontrollers may be configured to send the production and consumption values to the communications gateway 28 periodically, without prior receipt of a request for such information. Where the device 10 is for use with communications gateways provided by different third party suppliers, the microcontrollers may be programmed with an identifier of which of the protocols to use for communication. The device 10 can conveniently be installed at the same time that the solar panel system is installed. Alternatively, the device 10 can be appropriately retrofitted. The dwelling 20 may be a conventional house or apartment, and the associated at least one solar panel 26 may be installed on a roof thereof. The device 10 is typically located within the dwelling, but may, for example, be located on a roof thereof. The solar panel system 24 may include a battery. Referring to Figure 1, in an example the amount of electricity produced by the solar panel system 24 is that required by the dwelling 20, for example the amount produced is 3kW and the dwelling consumption is 3kW. Thus, it can be determined that no electricity was drawn from or supplied to the grid 22 from the production and consumption values. Referring to Figure 2, in another example, the amount produced by the solar panel system 24 is less than that required by the dwelling 20. For example, 3kW is produced and the dwelling consumption is 4kW. Thus, it can be determined that 1kW was drawn from the grid from the production and consumption values. Referring to Figure 3, in another example, the amount produced by the solar panel system 24 exceeds that required by the dwelling 20. For example, the production by the solar panel system 24 is 4kW and the dwelling consumption is 3kW. Thus it can be determined that 1kW was supplied to the grid from the production and consumption values. Referring to Figure 5, in use, when installed, the consumption meter 14 measures electricity usage by the dwelling. The production meter 15 measures electricity generated by the solar panel system. The communications gateway 28 periodically sends (step 100) requests for the consumption values and for the production values along the communications cable 17 (or to the gateway unit which relays the requests via the communications cable). The consumption meter 14 and the production meter 15 receive the requests intended for them, process the requests to determine a response, and send (steps 102 and 104, which may also be oppositely ordered) the response to the communications gateway 28 (or sends them to the gateway unit which relates them to the gateway 28). The responses include, in the case of the consumption meter 14, a value for electricity used by the dwelling, and in the case of the production meter 15, a value for electricity output at the inverter. The communications gateway 28 receives (step 106) the values and sends them to the online server 32 at step 108. The values may be processed to determine a value for electricity supplied to the grid 22 that was generated by the solar panel system (step 110) and this value is made available to the owner (step 112) at a monitoring portal such as an online interface, for example via a web browser or within an application. Information on production and usage by the dwelling may also be made available. The value for electricity supplied to the grid 22 enables the owner to understand a monetary value for the electricity generated by the solar panels 26 that was supplied to the grid. In some embodiments, the consumption and production meters 14, 15 each have an associated display (e.g. an LCD) coupled to the respective microcontroller, wherein the production and consumption values are each displayed on the respective display. As an alternative communications means to the communications gateway 28, a communications board (not shown) may be part of an inverter system comprising the inverter 30, the board being configured to provide the functionality ascribed above to the communications gateway 28. The applicant hereby discloses In isolation each individual feature or step described herein and any combination of two or more such features, to extent that such features or steps or combinations of features and / or steps are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or steps or combinations of features and / or steps solve any problems disclosed herein, and without limitation to the scope of the claims. The 5 applicant indicates that aspects of the present invention may consist of any such individual feature or step or combination of features and / or steps. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention.

Claims

1. A device comprising:a first meter for measuring electricity produced by a solar panel system associated with a dwelling and for causing sending of the first information; anda second meter for measuring electricity consumed at the dwelling and for causing sending of the second information.

2. The device of any one of the preceding claims, wherein the first and second meters are configured to receive requests for the first and / or second information from a communications means, wherein the sending of the first information by the first meter is caused in response to the receiving of a request for the first information by the first meter, and the sending of the second information by the second meter is caused in response to the receiving of a request for the second information by the second meter.

3. The device of any one of the preceding claims, wherein the first meter is connected to an output of the solar panel system (or invertor) for measuring the electricity produced by the solar panel system.

4. The device of claim 3, wherein the second meter is connected to an input cable to the dwelling for measuring the electricity consumed by the dwelling.

5. The device of claim 4, wherein the device is installed in the dwelling in the vicinity of a meeting of a cable for carrying import / export electricity from the grid, a cable for carrying electricity produced by the solar panel system, and the cable for carrying all electricity to be consumed by the dwelling.

6. The device of any one of the preceding claims, further comprising connecting means connected to the first and second meters for partially or wholly enabling the sending of the first and second information.

7. The device of any one of the preceding claims, further comprising a housing that houses at least the first meter, the second meter and the second means.

8. The device of claim 7, further comprising a circuit breaker housed by the housing, the circuit breaker being electrically connected between the first and second meters.

9. The device of claim 8, or claim 7 when dependent on claim 6, wherein the connecting means is partially or wholly housed by the housing.

10. The device of any one of claims 7 to 9, wherein the first and second meters each include a port, wherein the connecting means comprises at least one cable connecting the ports and for at least partially enabling sending of the first and second information.

11. The device of claim 10, wherein the connecting means comprises a gateway unit connected to the at least one cable, for receiving the first and second information from the first and second meters, respectively, using a first protocol, and relaying the first and second information to the communications means using a second protocol, and / or for receiving requests for the first and / or second information from the communications means using the second protocol, and relaying the requests to the first and / or second meters using the first protocol.

12. Apparatus comprising the device of any one of claims 1 to 10, further comprising further connecting means enabling communication between the device and the communication means.

13. The apparatus of claim 12, wherein the further connecting means comprises agateway unit connected to the connecting means, for receiving the first and second information from the first and second meters, respectively, using a first protocol, and relaying the first and second information to the communications means using a second protocol, and / or for receiving requests for the first and / or second information from the communications means using the second protocol, and relaying the requests to the first and / or second meters using the first protocol.

14. The device of any one of claims 1 to 11, or the apparatus of claims 12 or 13, wherein the communications means is configured to send the first and second information to a remote server.

15. The device or apparatus of claim 14 wherein the communications means comprises a communications gateway and / or a communications board of an inverter.

16. The device or apparatus of claim 15, wherein the first meter and / or the second meter is MID-approved and / or revenue grade.

17. A method comprising:sending, by a first meter at a device, first information indicative of electricity provided by a solar panel system, the solar panel system being associated with a dwelling;sending by a second meter at the device second information indicative of electricity consumed by the dwelling.

18. The method of claim 17, wherein the sending is in response to a request (e.g. a polling request) from a communications means.

19. The method of claim 18, wherein the receiving of requests and the sending of the first and second information is performed periodically.

20. The method of any one of claims 17 to 19, further comprising, sending, by the communications means, the first and second information to a remote server, wherein the server determines third information indicative of electricity provided to a grid using the first and second information.

21. The method of any one of claims 17 to 20, wherein the device comprises a housing that houses the first and second meters, and wherein the first and second meters are communicatively coupled to the communications means.

22. The method of claim 21, wherein the connection means comprises a gateway unit, wherein the unit relays requests from the communications means to the first and second meters and relays responses from the first and second meters to the communications means.

23. The method of any one of claims 17 to 22, wherein the first meter is connected to an output of the solar panel system (or invertor) for measuring the electricity produced by the solar panel system, wherein the second meter is connected to an input cable to the dwelling for measuring the electricity consumed by the dwelling, wherein the device is installed in the dwelling in the vicinity of a meeting of a cable for carrying import / export electricity from the grid, a cable for carrying electricity produced by the solar panel system, and the cable for carrying all electricity to be consumed by the dwelling.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWSCLAIMS1. A device comprising:a first meter connected to an output of a solar panel system (or invertor) associated with a dwelling, for measuring electricity produced by the solar panel system, and for causing sending of first information indicative of the measured electricity;a second meter connected to an input cable to the dwelling, for measuring electricity consumed at the dwelling and for causing sending of second information indicative of the consumed electricity; anda housing that houses at least the first meter and the second meter.

2. The device of any one of the preceding claims, wherein the first and second meters are configured to receive requests for the first and / or second information from a communications means, wherein the sending of the first information by the first meter is caused in response to the receiving of a request for the first information by the first meter, and the sending of the second information by the second meter is caused in response to the receiving of a request for the second information by the second meter.

3. The device of claim 1 or claim 2, wherein the device is installed in the dwelling in a vicinity of a meeting of a cable for carrying import / export electricity from the grid, a cable for carrying electricity produced by the solar panel system, and the cable for carrying all electricity to be consumed by the dwelling.

4. The device of any one of the preceding claims, further comprising connecting means connected to the first and second meters for partially or wholly enabling the sending of the first and second information.

5. The device of any one of the preceding claims, further comprising a circuit breaker housed by the housing, the circuit breaker being electrically connected between the first and second meters.

6. The device of claim 4, or claim 5 when dependent on claim 4, wherein the connecting means is partially or wholly housed by the housing.

7. The device of claim 4 or one of claims 5 and 6 when dependent on claim 4, wherein the first and second meters each include a port, wherein the connecting means comprises at least one cable connecting the ports and for at least partially enabling sending of the first and second information.

8. The device of claim 7, wherein the connecting means comprises a gateway unit connected to the at least one cable, for receiving the first and second information from the first and second meters, respectively, using a first protocol, and relaying the first and second information to the communications means using a second protocol, and / or for receiving 5 requests for the first and / or second information from the communications means using the second protocol, and relaying the requests to the first and / or second meters using the first protocol.

9. Apparatus comprising the device of any one of claims 1 to 7, further comprising further connecting means enabling communication between the device and the communication 10 means.

10. The apparatus of claim 9, wherein the further connecting means comprises a gateway unit connected to the connecting means, for receiving the first and second information from the first and second meters, respectively, using a first protocol, and relaying the first and second information to the communications means using a second protocol, and / or for 15 receiving requests for the first and / or second information from the communications means using the second protocol, and relaying the requests to the first and / or second meters using the first protocol.

11. The device of any one of claims 1 to 8, or the apparatus of claims 9 or 10, wherein the communications means is configured to send the first and second information to a remote ’0 server.

12. The device or apparatus of claim 11, wherein the communications means comprises a communications gateway and / or a communications board of an inverter.

13. The device or apparatus of claim 12, wherein the first meter and / or the second meter is revenue grade.25 14. A method comprising:sending, by a first meter housed at a device, first information indicative of electricity provided by a solar panel system, the solar panel system being associated with a dwelling;sending by a second meter housed at the device second information indicative of electricity consumed by the dwelling, wherein the first meter is connected to an output of the 30 solar panel system (or invertor) for measuring the electricity produced by the solar panel system, wherein the second meter is connected to an input cable to the dwelling for measuring the electricity consumed by the dwelling.

15. The method of claim 14, wherein the sending is in response to a request from a communications means.

16. The method of claim 15, wherein the sending of the first and second information is 5 performed periodically.

17. The method of any one of claims 14 to 16, further comprising, sending, by the communications means, the first and second information to a remote server, wherein the server determines third information indicative of electricity provided to a grid using the first and 10 second information.

18. The method of any one of claims 14 to 17, wherein the device comprises a housing that houses the first and second meters, and wherein the first and second meters are communicatively coupled to the communications means.

20. The method of claim 18, wherein the connection means comprises a gateway unit, 15 wherein the unit relays requests from the communications means to the first and second meters and relays responses from the first and second meters to the communications means.

21. The method of any one of claims 14 to 20, wherein the device is installed in the dwelling in the vicinity of a meeting of a cable for carrying import / export electricity from the grid, a cable for carrying electricity produced by the solar panel system, and the cable for carrying all 20 electricity to be consumed by the dwelling.s

Images