We were told by our solar installer that the laws were changing in Thailand by the end of year last year that would allow folk to connect solar systems to the grid without the reporting requirement. So, as we installed at the end of October, I manually disconnected the system for about two weeks in November, and two weeks in December, just to limit the production "below the radar" and wait it out for the new year. I have yet to see the law in print that gives us the freedom we supposedly should have this year, but I have just let it run and have yet to face any issues.
The problem in our case was not so much getting permission as the need to pay around $600 for an engineer's signature after inspecting the setup. We could easily have filed for the permit, but the engineer part of it would have added considerably to our installation cost. So far, we have not been confronted over it, and the system is not visible from the road (although the CT is obvious now right next to the meter). Perhaps this month, when the meter reader sees the CT, he'll have something to say...wait and see.
For off-grid stuff, I think a "don't ask, don't tell" policy is generally preferable, and where I am it is not regulated anyhow.