Bruce:

6.7 amps running 24/7 is 6.7X24x30 = 4824 amp-hours per month. Multiply by 115v to get volt-amp-hours (watt-hours) is 4824x115 = 554,760 watt-hours per month, divide by 1000 gives 555 kilowatt-hours per month.

Check your electric bill and you should be able to see how much a kilowatt-hour costs you, delivered. IIRC (and it's a WAG) a very ROM figure nationally is $0.11 per kilowatt-hour, which would be $61.05 per month, IF my math is good and IF that $0.11 per kilowatt-hour is valid. Your own electric bill is the best source on cost anyway.

P.S. Are you still claiming that empty DMD can is in the photo just to provide info on the size of the hardware? \:D

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