The challenge here is the other costs that are unaccounted for. Sure, you see power at 5c/10c per KWH, but all the other parts cost money as well, such as poles. Sure, the pole may be split in cost between the power, phone and cable companies, but that's still an expensive asset. http://www.dailyherald.com/art... provides a view into what this costs to be maintained. If a pole costs $1-3k, how many are you sharing the cost of as part of the rate. This is part of the "ugly profit" people gripe about with some of these shared assets, both in an electric network and the ways the bits reach your screen here.
If I get to a bill of zero due to investing and net-metering, someone else is going to be paying for those grid parts either in higher rates, or I need to pay for some usage of that giant battery network. No free lunch, etc..