I've got (so-far) three smart meters at home
A reads the left side of the house for one energy supplier [or it should] (LCD display has failed so I can no longer read it locally - I'm going to have to wire an arduino up to count the kWh led pulses)
B reads the right side of the house for another energy supplier
and a third one C checks what output my main FIT PV-array has, (installed immediately after the inverter to ensure that I don't cheat to get bigger FIT payments) [or they should]
The reality is that all my meters are read by company B, who sometimes send my consumption data to company A for billing, [once they delayed the data by a whole year] My B & C smartmeters are also not accurate for receiving my FIT payments as I'm simply receiving "an average" for my 3kWp array - I'm getting identical payments to a local friend. Maybe one-day they will correct with over/under payments?
As a new hobby, I've just bought a new set of PV components (from a major online book-seller) :- couple of "12V" 100Wp poly modules from somewhere in the EU@£80-ish each and a £79 MPPT 18V 600W grid-tie micro-inverter. I'll be feeding this 230V into smartmeter A, checking carefully to ensure that it doesn't register my generation as power-consumption! [smartmeters often don't run backwards] I hope to just get rid of my base-load on that side of the house. All lights are already LED.
In this part of the EU I was given no-option / zero choice about the first two meters, and had to accept the checksum meter as part of the FIT contract. It's good that you might get a choice in UK, if you say "NO" a lot when offered.
The initial load-shedding function hypothesis envisaged of smartmeters is that they will connect through a domotic API for turning off the fridge and freezer for a few hours [without any risk of spoiling the food], then progressively shed further loads until potentially fully off. However it seems that the current generation doesn't do that, my fridge & freezers certainly don't do that, and I don't really want to pay multi-millions to billions to implement this, without a lot more debate.