At $141 per miser in our use case, we paid ours off in savings in roughly 5 months.
We pay 10 cents per kwh. We have 33 machines (30 pins and 3 arcades). Figure 200 watts per hour per machine with normal play and we're open 19hrs per day.
Without misers and the machines on for 19hrs we figure $382 per month in power.
http://www.rapidtables.com/calc/electric/electricity-calculator.htm
-ALWAYS ON-
6600 total watts (33 machines x 200 watts / machine)
19 hours "on" time per day
10 cents per KWH
Misers cutting down total "on" time to 7 hours overall across everything brings it down to $141.
A savings of $241 a month in power for the machines. (or roughly 5 months to pay for 8 misers)
Bill
Fargo Pinball
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