STRATEGIC REDUCTION OF POWER USAGE IN MULTI-SENSING, WIRELESSLY COMMUNICATING LEARNING THERMOSTAT

• US 20120179300A1
• Filed: 10/06/2011
• Published: 07/12/2012
• Est. Priority Date: 09/14/2010
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Nest Labs Incorporated (Alphabet Inc.)
• Inventors: WARREN, Daniel Adam, RUFF, Joseph Adam, ERICKSON, Grant M., MUCIGNAT, Andrea, SATTERTHWAITE, Edwin H. Jr., PALMER, Joseph E., HONJO, Shigefumi
• Granted Patent: US 9,026,254 B2
• Time in Patent Office: Days
• US Class Current: 700/278
• CPC Class Codes: B01D 46/0086 Filter condition indicators
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/32 Responding to malfunctions or emergencies
• CPC Class Codes: F24F 11/39 Monitoring filter performance
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/47 Responding to energy costs
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/56 Remote control
• CPC Class Codes: F24F 11/58 using Internet communication
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/62 characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 11/64 using pre-stored data
• CPC Class Codes: F24F 11/89 Arrangement or mounting of control or safety devices
• CPC Class Codes: F24F 2110/00 Control inputs relating to air properties
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2120/10 Occupancy
• CPC Class Codes: F24F 2120/20 Feedback from users
• CPC Class Codes: F24F 2130/40 Noise
• CPC Class Codes: F24F 2140/00 Control inputs relating to system states
• CPC Class Codes: F24F 2140/60 : Energy consumption
• CPC Class Codes: G05B 13/0265 : the criterion being a learning criterion
• CPC Class Codes: G05B 15/02 : electric
• CPC Class Codes: G05D 23/19 : characterised by the use of electric means G05D23/1393 takes precedence
• CPC Class Codes: G05D 23/1902 : characterised by the use of a variable reference value
• CPC Class Codes: G05D 23/1917 : using digital means
• CPC Class Codes: H01R 9/2416 : Means for guiding or retaining wires or cables connected to terminal blocks
• CPC Class Codes: H04W 4/70 : Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: Y02B 10/20 : Solar thermal
• CPC Class Codes: Y02B 10/70 : Hybrid systems, e.g. uninterruptible or back-up power supplies integrating renewable energies
• CPC Class Codes: Y02D 30/70 : in wireless communication networks
• CPC Class Codes: Y10T 29/49826 : Assembling or joining

Abstract

In a multi-sensing, wirelessly communicating learning thermostat that uses power-harvesting to charge an internal battery, methods are disclosed for ensuring that the battery does not become depleted or damaged while at the same time ensuring selected levels of thermostat functionality. Battery charge status is monitored to determine whether the present rate of power usage needs to be stemmed. If the present rate of power usage needs to be stemmed, then a progression of performance levels and/or functionalities are scaled back according to a predetermined progressive power conservation algorithm. In a less preferred embodiment, there is a simple progressive shutdown of functionalities turned off in sequence until the desired amount of discharge stemming is reached. Battery charge preservation measures are also described for cases when an interruption of external supply power used to recharge the battery is detected.

Claims

1. A method for strategically reducing power usage in a thermostat having a rechargeable battery comprising:

supplying power for a plurality of thermostat activities using a rechargeable battery located within the thermostat;

making at least one measurement associated with the rechargeable battery; and

automatically altering one or more of the thermostat activities based at least in part on the measurement so as to reduce power usage from the rechargeable battery.

2. A method according to claim 1 wherein the thermostat activities includes sensing from a plurality of sensors.

3. A method according to claim 1 wherein the thermostat activities includes wirelessly communicating.

4. A method according to claim 1 further comprising harvesting power from an HVAC system being at least partially controlled by the thermostat, the harvested power being used at least in part to charge the rechargeable battery.

5. A method according to claim 1 wherein the altering of the one or more of the thermostat activities is carried out in a progression of stages in which each stage is associated with altering a predetermined set activities, and the stages are progressed based at least in part on the measurement associated with the rechargeable battery.

6. A method according to claim 5 wherein between three and six stages are used ranging between nearly fully charged battery and nearly drained battery.

7. A method according to claim 1 wherein each of the one or more thermostat activities is altered depending on a predetermined threshold for that activity.

8. A method according to claim 1 wherein the measurement associated with the rechargeable battery includes a measure of remaining battery charge level.

9. A method according to claim 8 wherein the measurement is battery voltage.

10. A method according to claim 1 further comprising estimating remaining battery capacity based in part on current activities being carried out by the thermostat, wherein the altering is based at least in part on the estimated remaining battery capacity.

11. A method according to claim 1 further comprising estimating remaining battery capacity based in part on a measurement of power being drawing from the battery, wherein the altering is based at least in part on the estimated remaining battery capacity.

12. A method according to claim 1 wherein the altering of one or more of the thermostat activities includes reducing a backlighting level of a display of the thermostat.

13. A method according to claim 1 wherein the altering of one or more of the thermostat activities includes altering wireless communications being used by the thermostat.

14. A method according to claim 1 wherein the altering of one or more of the thermostat activities includes altering a frequency at which a measurement is made with a sensor.

15. A method according to claim 1 wherein the altering of one or more of the thermostat activities includes altering the operation of one or more learning algorithms being carried out by the thermostat.

16. A method according to claim 1 wherein the altering of one or more of the thermostat activities includes altering the operation of aspects of a user interface.

17. A method according to claim 1 wherein the altering of one or more of the thermostat activities includes, in an HVAC system having more than one stage of heating or cooling, disabling one or more of the stages.

18. A method according to claim 1 further comprising attempting to notify a user that the available power within the thermostat is being depleted.

21. A thermostat comprising a processing system and other components adapted and arranged to carry out a method according to claim 1.

19. A method according to claim 19 wherein the attempt to notify includes wirelessly transmitting a message to a computing device.

20. A method according to claim 19 wherein the attempt to notify includes displaying a notification on a display of the thermostat.

22. A thermostat comprising:

a plurality of components that consume electrical power;

a rechargeable battery for providing power to at least some of the plurality of components; and

a processing system adapted and programmed to automatically alter thermostat functionality so as to reduce power usage based at least in part on a measurement associated with the rechargeable battery.

23. A thermostat according to claim 22 wherein the plurality of components includes a plurality of sensors, and one or more systems for wireless communication.

24. A thermostat according to claim 22 further comprising power harvesting circuitry adapted to harvest power from an HVAC system for use in charging the rechargeable battery.

25. A method for reducing power usage in a thermostat having rechargeable battery comprising:

supplying power for a plurality of thermostat activities using a rechargeable battery located within the thermostat, the rechargeable battery being ordinarily recharged using power from an external power source;

detecting an lack of power from the external power source; and

automatically altering one or more of the thermostat activities based at least in part on the detecting of the lack of power from the external source, so as to reduce power usage from the rechargeable battery.

26. A method according to claim 25 further comprising making at least one measurement associated with the rechargeable battery, wherein the automatic altering is based in part on the measurement.

27. A method according to claim 26 wherein the measurement is battery voltage.

28. A method according to claim 25 wherein the thermostat activities are maintained in a reduced state for a first predetermined amount of time following the detecting of the lack of external power, unless an external power source suitable for recharging the battery is detected.

29. A method according to claim 25 further comprising disconnecting the rechargeable battery from at least a portion of electronics within the thermostat so as to conserve power within the rechargeable battery.

30. A method according to claim 25 wherein the automatic altering includes shutting down at least one processing system within the thermostat.

31. A method according to claim 30 further comprising booting up the at least one processing system that had been shut down, when an external power source suitable for recharging the battery is detected and the battery is charged above a predetermined level.

32. A method according to claim 25 further comprising attempting to notify a user that of the detected lack of external power.

33. A thermostat comprising a processing system and other components adapted and arranged to carry out a method according to claim 25.