No it's not an unfair bet because many pay less than $0.1/kwh for home electricity but almost nobody pays less than $0.15/kwh for DC hosting.
Normal miners have 50-2000w worth of hardware.
Big mining operations (50kw+) will not care about weight(shipping pallets is cheap) and they won't care 50% efficiency since they pay less than $0.05/kwh.
Sp30s are for those miners who are somewhere inbetween which is inefficient because you need to pay someone to host them.
Average electricity rate in US is .16 it can vary as low as .08 in Washington to as high as .37 in california and new york. MIne here in PA is .16 total, you are looking at rate of electricity cost and delivery, etc. This is total cost on your bill.
Most sources dont have the total cost.
http://cleantechnica.com/2013/09/30/average-electricity-prices-around-world/
Add another .04 to .05 to the US for correct prices, for delivery, for the transportation use of lines etc.