P1 port is specifically to read values and “open”. There a 10€ cable to convert it (passively) to usb.

You could consider one of those clamps that measure the power through a cable from the fields around it?

Actually, it is just serial under the hood, although electrically slightly nonstandard.

No doubt about the tampering comment. However, my gas, water, and electric meters are all wireless and now I want to be able to monitor them for on demand usage. We shall see.

Has there been talk about that becoming a thing?

In PG&E land, you can buy one of a handful of approved ZigBee gadgets that can read out your meter data.

If you can recommend one of these gadgets... I'd really appreciate it.

I've heard that it's hard to measure gas in residential contexts, because the pressure is so low.

This is not utility infrastructure. It’s a submeter connected to a set of current transformers.

In general in the US, for commercial buildings, everything beyond the utility transformer secondary is the responsibility of the customer. For a residence, anything beyond the meter socket is the responsibility of the customer.

I’m unfamiliar with UK utility standards though so perhaps it’s different there.

Weird. You have a meter, after the utility's meter, that you can just plug into?

At least in the netherlands and belgium, the meter is from the utility company, but comes with a public serial port (the so called P1 port) to read the data for smart home purposes.

Not by default, but tenant submeters are something you can install in your own premises wiring. Here’s an example, a single-phase meter made by Honeywell: https://prod-edam.honeywell.com/content/dam/honeywell-edam/h...

The linked example only monitors one circuit, but you could buy a submeter than can monitor multiple current transformers/multiple circuits.

The utility meter is supplied by the utility and used to bill you, an optional submeter is just for your own monitoring and tracking of electrical use.

This isn’t tampering, but using an interface expressly designed for this purpose.

See https://www.netbeheernederland.nl/_upload/Files/Slimme_meter.... I think that’s more than good enough for third parties to use.