Thinking of using Splitter Trough to avoid up-sizing main breaker panel

[Ampster]

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The local util rolled out new digital meters a few years back ... might be close to 10 years back, but they are all uni-directional only.
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Hopefully they were smart meters that can be read electronically.

[foo1bar]

I understood him to say one unidirectional meter in the usual spot and another unidirectional meter reversed and placed on just the solar feed. Different wires and devices measuring flows in different directions. I agree it is inefficient.

I reread his post again - and no, he is not describing the 2nd meter being for just the solar feed: " If you are going the net metering way then you need to add a second meter which is connected next in line with the existing meter. "

If it were a meter for SRECs, it'd make sense as you describe - have it on the wires for the solar, measuring all the solar production.
But the way his utility has it setup they do two unidirectional meters instead of a single bidirectional one.
Only reason I can think of is that their billing system needs them to have two separate meter numbers doing the reporting.
If they enabled bi-directional on their current meters (which I'm sure being digital, they have that capability) maybe that mode doesn't interface the utility billing software nicely.
I can't think of any other reason to have two pieces of equipment when one would do - I would bet those digital meters can be switched from uni-directional to bi-directional real easily - probably with just a command typed in the central office)

[foo1bar]

In our snowy area outside breaker panels are basically unheard of. We save our shovelling muscles for the driveway.

I grew up in that kind of climate - and it would be really weird for someone to have an outside breaker panel - they were practically always in the basement (because everyone had a basement)
For your situation though - the outside panel would basically never be opened after it was installed. When you trip the breaker because you had the microwave running on the same circuit as the Nesco roaster and the coffee pot, you'd still go down to the panel in your basement, not outside.

Also - you're going to have a panel outside for your solar system, even if you do have a load-side tap.
There *MUST* be a fuse/breaker between the power company's lines and your inverter.
So if you do it as a tap (in what you've called a splitter trough) - there will have to be a breaker panel nearby. For the 3 wires being joined together in that "splitter trough", one goes to the meter, one goes to your current main panel in the basement, and one goes to the new solar breaker panel (which you'll likely mount outside near the meter and inverter)

If you do it with a new main panel, the new main panel sits next to your new meter and has wires to it - and from that new main panel there are wires that go to your inside panel - and wires that go to your inverter.

The ground/common wiring might have to be redone a little bit for what had been the main panel when it becomes a subpanel. But probably wouldn't be that bad.

[Ampster]

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Only reason I can think of is that their billing system needs them to have two separate meter numbers doing the reporting.
If they enabled bi-directional on their current meters (which I'm sure being digital, they have that capability) maybe that mode doesn't interface the utility billing software nicely.
I can't think of any other reason to have two pieces of equipment when one would do - I would bet those digital meters can be switched from uni-directional to bi-directional real easily - probably with just a command typed in the central office)

I think your assumptions are correct. I have had solar with two utilities in California and as soon as my Permission to Operate was received, some toggle was done at the central office and the accounting software started logging my net generation. I could see the meter record the net generation before the PTO was received during a time when the installer was testing the system.