load average (kWh): 270, 220, 230This can be done -- today, easily and cheaply. Here's how:
Appliances: 149 total
Appliance kWh %tot
Fridge 130 60
Stove 90 30
Desk lamp 60 10
- Have a simple device that sits on a circuit and measures the power consumption. Kind of like the Kill-a-watt, except without the readout screen and the buttons. These devices can probably be easily built-in into outlets and power bars.
- The sensor has a unique identifier (similar to a mac address). This identifier is clearly labelled on the outlet.
- Every N seconds/minutes the sensor broadcasts the consumption data along the power line (just like "smart meters" do). Something like "00:0b:db:79:4e:45#120W" to indicate that the sensor with a unique id "00:0b:db:79:4e:45" is currently reporting 120 watts.
- A listener device plugs in to the power grid in your home and collects the reports, which it then either presents on a readout screen, or makes available to the network via, say, an SNMP service.
- You have some fairly simple software on your computer that connects to the listener device and shows you real-time power usage using nice graphs. You can give human-friendly labels to the sensors to identify them for your own use (e.g. you locate the outlet labelled "00:0b:db:79:4e:45" and know that it's where your fridge is plugged in, so you label that sensor as "Fridge" in your software).
- The software can even present the graphs in real money instead of kWh -- this way you'll know that the lights you left on in the bedroom are currently costing you 2 cents per hour, and the 1000W heater you leave on in your garage just in case you have to go down there runs up a nice $2.00 a day.
Judging from how much us geeks are obsessed about things like network graphs and memory graphs, I'd say that a system like this would prove pretty popular. Does someone care to take it and run with it? :)
(I have no idea if this has occurred to anyone else before, or if similar systems are already available out there. I didn't find anything from superficial googling, so I assume that no).