I wanted to know exactly how much power my miners were consuming, so I decided to measure. I purchased a Kill-a-Watt power meter. I started with my Bitmain AntMiner S2.
The Kill-a-Watt is extremely easy to use. You just plug your device (in this case my S2 miner) into the Kill-a-Watt, plug the kill-a-Watt into your power outlet, turn on your device and you get immediate information about the power consumption of your device: Voltage, Amperage, Wattage, and power in Kilowatt-hours.
First some terms:
Current = The amount of electricity (actual electrons) flowing through a circuit at any one time. Standard unit is Ampere or Amps. 1 Amp is 1 coulomb of charge (6.241 x 10^18 electrons) per second.
Voltage = A unit of potential energy. The amount of energy that would push 1 ampere (amp) of current through 1 Ohm of resistance.
Watt = Standard unit of power. Power is a measure of force exerted over time. A Watt is 1 amp at 1 volt.
Kilowatt-hour (KWH) = This is the normal unit that electrical energy is sold in in the United States. It is the number of kilowatts (one thousand watts) consumed over 1 hour (3600 seconds) of time.
My Bitmain AntMiner S2 bitcoin miner uses:
at 120 volts
or 1065 Watts
If you let the Kill-a-Watt continue to measure, over time, it will keep track of the total KWH consumed by the device. I left the setup connected for a full 24 hours of mining. The AntMiner S2 consumed 27.56 KWH for a day of mining.
Using this number it is simple to calculate the cost of running a miner. Stay tuned for that analysis.