Power-preserving communications architecture with long-polling persistent cloud channel for wireless network-connected thermostat

A method of controlling an environmental condition, the method comprising:

• charging an energy-storage device using a first power harvested from an external power source;
• powering a circuit at least in part with energy from the energy-storage device, wherein:
• the circuit is configured to operate in a low-power mode;
• and
• the circuit is configured to operate in a high-power mode;
• establishing one or more communication channels with a server;
• communicating with the server using a protocol, wherein the protocol comprises:
• a first type of transmission comprising keep-alive messages sent from the server at least in part to maintain one or more communication channels,
• a second type of transmission characterized as having a high environmental priority and comprising information for controlling the environmental condition;
• and
• a third type of transmission characterized as having a low environmental priority and comprising information associated with updating the circuit itself;
• and
• discriminating between transmissions of the first type, transmissions of the second type, and transmissions of the third type;
• in response to identifying a transmission of the first type during a time period in which the circuit is operating in the low-power mode, allowing the circuit to continue operating in the low-power mode and discarding the transmission of the first type;
• in response to identifying a transmission of the second type during a time period in which the circuit is operating in the low-power mode, causing the circuit to transition from the low-power mode to the high-power mode, and forwarding the transmissions of the second type to the circuit to control the environmental condition;
• and
• in response to identifying a transmission of the third type during a time period in which the circuit is operating in the low-power mode, saving the transmission of the third type until the circuit has transitioned to the high-power mode, then forwarding the transmission of the third type to the circuit to update the circuit itself.

A thermostat, comprising:

• a plurality of heating, ventilation, and air conditioning (HVAC) connectors;
• an energy-storage device;
• a processor;
• and
• a wireless communication module operatively coupled to the processor and configured to:
• establish and maintain wireless communications with a router, including receiving transmissions from the router;
• and
• process the transmissions from the router by discriminating between a first type of transmission, a second type of transmission, and a third type of transmission, wherein:
• the first type of transmission comprises keep-alive messages associated with a communication channel sent from a remote thermostat-controller server to the thermostat,
• the second type of transmission is characterized as having a high thermostatic priority and comprising information associated with controlling the HVAC system;
• and
• the third type of transmission is characterized as having a low thermostatic priority and comprising information associated with updating the thermostat itself;
• and
• during times when the processor is operating in a low-power state:
• discard transmissions from the router of the first type;
• cause the processor to transition from the low-power state to a high-power state in response to receiving transmissions of the second type, and forwarding the transmissions of the second type to the processor to control the HVAC system, and
• save transmissions of the third type until the processor has transitioned to the high-power state, then forwarding the transmissions of the third type to the processor to update the thermostat itself.