It is interesting to see what’s on the internet. As a “bread and butter” {economic survival} issue, my take in the US is that mainstream electrical folks {inspectors and contractors} support building codes, with or without a 60Hz feed from somewhere. There certainly are cases of “If you don’t get caught you’re OK” frame of mind. It’s being done formally and legally in California and other west coast states, and there is one unusual twist—selling back excess AC power to electric utilities. Some sites are
www.homepower.com www.realgoods.com/renew/index.cfm www.traceengineering.com www.nikolasolar.com

(There are a number of other links at the cited ones here.)