For starters, there would have to be energy costs of <USD$0.08/kWh and periodic coin investment at a return-generating depository.
Well,I was talking about a fact that person will take all energy cost.
So the main idea right now is that there is all most no point in building GPU mining system with current hardware.So are investors ready to invest in system in order to maintain it. Or we could get even hashing power down in near future. Because FPGA\ASIC are not widespread, there is all most no warranty for them + they win only in power efficiently and scalability, which suits for big mining farms, but this doesnt seems to be rights for the system. So ordinary people could get interesting in building farms, paying for cpu,psu,so on, if they would get GPU free after some time. And they will maintain network in good condition,using p2p pool.
Are there some one interested in it. Or this is pointless?