No, economies of scale apply.
With current mainstream technologies you can get a hefty competitive advantage by getting industrial rather than residential power rates. In my neck of the woods that cuts the power cost nearly in half (less if you shut down during peak times).
With current mainstream technologies you can get a hefty competitive advantage by getting industrial rather than residential power rates. In my neck of the woods that cuts the power cost nearly in half (less if you shut down during peak times).
The residential user in some areas can get electric rates lowered if they are willing to intergrate their demands into the power company's smart network so that they can directly reduce demand. For a time, I had a programmable thermostat that would do exactly that. It would be trivial for such an input to control the residential miner as well.
That aside, the professional miner is certainly going to dominate, but mining will never be an exclusively professional endeavor. If I use a small miner as a heater in my garage, linked to a thermostat or not, but only during the heating season for my area, the cost of electricity for mining is, at worst, only the difference in the cost between electric resistive heating and the least expensive alternative available in my area. This is exactly why I say that Icelanders are uniquely well suited to owning small, personal mining clusters.
Excellent point on the home heating arguments. If I'm not mistaken all resistive heaters have the same efficiency. So ignoring the kinetic energy used to turn your fans for a moment, all electrical energy going into your computer is turned in heat energy. In instead of buying a 1000w heater, you might as well make a 1000w mining rig.
. Oh well... 
