Apparatus and method for sub-metering of household devices
An apparatus and method for estimating resource consumption of a household device, e.g., an appliance. The method comprises determining a resource demand profile for a household device for a given time period, the resource demand profile associating, for the given time period, a device state of the household device with a total resource demand for the household. In one embodiment, the apparatus can be incorporated into an energy management system, where the apparatus collects data from each of the appliances in a household as well as from a resource meter.
1. An apparatus configured to monitor resource consumption of an appliance in a household, said apparatus comprising:
a processor;
a memory coupled to the processor; and
one or more executable instructions stored on the memory and configured to be executed by the processor, the one or more executable instructions comprising instructions for:
determining a resource demand profile for a household device for a given time period, the resource demand profile associating, for the given time period, an operating state profile of the household device with a total resource demand profile for the household.
2. The apparatus of claim 1 , further comprising instructions for displaying the resource demand profile via a graphical user interface.
3. The apparatus of claim 1 , wherein the device state comprises a voltage level for a relay switch.
4. The apparatus of claim 1 , further comprising instructions for communicating with a thermostat.
5. The apparatus of claim 1 , further comprising instructions for monitoring a temperature sensor, wherein the temperature sensor provides an input indicative of an indoor temperature and an outdoor temperature, and wherein the input identifies values for the operating state profile.
6. The apparatus of claim 1 , further comprising instructions for communicating an input to the household device, wherein the input activates and/or deactivates the household device.
7. The apparatus of claim 1 , wherein the given time period identifies at least one hour of operation of the household device.
8. An apparatus, comprising:
a processor;
a memory coupled to the processor; and
one or more executable instructions stored on the memory and configured to be executed by the processor, the one or more executable instructions comprising instructions for:
receiving data from a household device and a resource meter that measures a total resource demand for the household; and
applying a least squares method to the data to determine a resource demand profile for the household device,
wherein the resource demand profile associates, for a given time period, an operating state profile for the household device and a total resource demand profile.
9. The apparatus of claim 8 , wherein the least squares method determines the values for the resource demand profile in accordance with:
P T =θ′*X,
wherein P T defines the total resource demand for the household, θ defines the values for the resource demand for the household device, and X defines the device state during given time period.
10. The apparatus of claim 8 , further comprising instructions for displaying the resource demand profile via a graphical user interface.
11. The apparatus of claim 8 , further comprising instructions for automatically updating the data at a predetermined interval.
12. The apparatus of claim 8 , further comprising instructions for sampling the data for the household and the household device at a sampling rate that is less than the given time period.
13. The apparatus of claim 8 , wherein the least squares method determines an estimation error e(k) in accordance with:
e ( k )= P T ( k )−θ′( k− 1)* X ( k ),
wherein k is a time step, P T (k) defines the total resource demand for the household at the time step, θ(k−1) defines the values for the resource demand for the household device at the previous time step, and X(k) defines the device state at the time step.
14. The apparatus of claim 13 , wherein the least squares method determines values for the resource demand profile in accordance with:
θ( k )=θ( k− 1)+ L ( k ) X ( k ) e ( k ),
wherein k is a time step, θ(k−1) defines the values for the resource demand for the household device at the previous time step, L(k) defines the least square gain at the time step, and X(k) defines the device state at the time step.
15. The apparatus of claim 14 , further comprising receiving an input indicative of the given time period.
16. The apparatus of claim 14 , wherein the household device comprise a thermostat.
17. A method, comprising:
at a remote device comprising a processor and memory:
determining a resource demand profile for a household device for a given time period, the resource demand profile associating, for the given time period, an operating state of the household device with a total resource demand profile for the household.
18. The method of claim 17 , further comprising applying a least squares method to the data to determine a resource demand profile for the household device.
19. The method of claim 17 , wherein the operating state is indicative of operation of an HVAC system.
20. The method of claim 19 , wherein the household device comprises a thermostat.