All radio communications equipment has to meet government licensing requirements, which means you can look up their frequency and power. As best I have been able to determine so far, “smart” meters use either the existing cellphone network, or frequencies 1GHz or lower, similar to wireless LAN, and all are less than 1 watt.
You’re picking up erroneous ideas by uncritically accepting the word of people like Trower. Anyone can claim anything, especially on the Internet, but that doesn’t make it true. Uncritically propagating such stuff just adds to the fog of confusion, which hinders people’s ability to understand.