I'm 2 Episodes from being caught up, I also missed one of the carry over episodes from the break (Where the kid dies)--so, I'm missing pieces, but this is for the people that were following and stopped at the break because the show was awful.
Firstly, the show has gotten better. It's still not a "good" show, but it's gone from comically bad to mediocre. The writing can still be obtuse at times, but the plots, pacing and explanations have been pretty refreshing. The characters are far, far less one dimensional and cliche--though they are still pretty shallow. It's just a lot "less" shallow than before--This is partially because the writing is better and because the actors are doing slightly better with their parts. It's also because the shows focus is far less on Dany and more on Miles, The mother, hot Hispanic lady and Gus Fring. The acting is still very, very bad compared to shows like GoT, but its better than most network TV, so take that as you will.
Now for the electricity.
The electricity went out, as posted in this thread, because they made first generation nano-bots. Tiny virus sized machines that can take simple commands. From what I can tell, these were NOT originally planned to stop the electricity, rather they were just machines meant to reproduce and accept simple orders--the intention was to have them form electrical grids without wiring. They can be controlled in a robust manner as long as they have a central computer and broadcasting equipment controlling them (It also seems like they can communicate back to this central computer). So they can always deliver and conduct the precise amount of power needed to X or Y equipment--so essentially wireless, cheap, universally deliverable electricity for all (With a super AI computer controlling it). This amount of control ALSO allowed the bots to do be controlled for other tasks, like healing, vaporizing people and also shutting down things like electrical flow.
What seems to have happened is the DARPA guy in charge of this funding built a huge tower and took control of the nanites. His command was to simply absorb and block electrical signals. They do not explain why this doesn't affect the human body. Guessing they are going to "hand wave" and say the tower can send out signals that differentiate between electrical signals produced by living tissue and inorganic matter. Which given it's been established that the computer controllers of the nanites can have them do very complex tasks like bone surgery or tumor removal, this is not out of the established realm of the show.
It's revealed that all this advanced nanite control is based off of Google-guys programing (He didn't know about it, supposedly he developed super-magic algorithms and these guys stole it to control their nanites.). With a central computer and programming these swarms of trillions of nanites can be used to do just about anything. She even called a book with code on how to control the nanites to do certain functions like a "spell book". So pretty much it's like the nanites have made our world into a giant video game, and anyone who can program a complex enough code to control billions of them with super-advanced magic algorithms can do just aboutanything.
This also explains why things work without shorting out when the lockets are around. This isn't said yet directly, but I'm inferring that the lockets aren't just a switch that shut the nanites off. Rather, much like the "control" computers which healed Dany's brother, they are little control systems which direct the nanites to power machines around them--the reason why the machines don't short is because it seems that the nanites can relay information back to the control system in order to be directed (This is the only way I could explain how the healing ect worked--the nanties are in constant communication with their control center.)...So the locket isn't shutting the nanites "off" at all, rather it's changing their programming so they are using the tiny amounts of stored power to give the equipment around them enough juice to turn on without being fried. (Which was their original intent, to be able to deliver electricity through the air and universally to all machines.)
I guess further hand waving will allow things that run off fuel to work with this, too? Maybe the nanites just push helicopter blades around and shit, I don't know. Anyway, still plenty of plot holes, but I was pleasantly surprised at them making a "tolerable" explanation--even if it is well within the "magic" territory still. At least if you can believe we had computer's advanced enough to control trillions of individual units in perfect harmony, that only occupy the size of a thumb, and a super advanced AI to direct it all, it's not out of the realm of possibility. So they've moved from "magic" to "Science Magic". Or just very very loose Sci Fi.
Anyway, TLDR. Show has gone from laughable horrible, to "mediocre" (It really has improved MASSIVELY)--which given how little Sci-Fi is on, makes it watchable for me. It would be better if they stopped doing bullshit like one guy taking down twenty but then when two "boss" characters meet neither of them can hit ect. But meh, at least it's not laughable now (Well not ALL the time, it has it's moments).