This is a known issue. Although the clamps are able to measure current flow either direction, currently Emporia is taking the absolute value of the current readings. Loads are always shown as positive, and solar always negative. The feature has been requested – vampire draw of the solar inverters is not taken into account as you note.
I need the Solar clamp to show positive and negative number, in order to measure my production of my sol-ark … Basically need to 2 CTs in front of the inverter, and 2 CT on the subpanel/protected feed, at night this should show cancel each other out in the calculations. however at day it should calc a generation amount even if not sending it back to the grid.
With my setup I have 2 AC to DC chargers tapped into my 240v (2x 120v) live microinverters lines so that I can show reduced production. Due to the absolute values for solar, it shows production when I’m actually in consumption thus breaking all my solar smart plug automation.
It essentially renders all my emporia stuff useless.