Although energy cannot be negative it is effectively seen as negative (for costing) when it flows in the reverse direction.
What I would expect is that if the current is negative the energy consumed is reduced or it is not counted in same value/register but kept track of in another register.
In my case I measure what my home is consuming effectively and when the sun is shining the inverter(s) deliver to the grid. And we pay for the difference in some period.
I know that power meters we are using at my work (of brands Socomec and Janitza) keep the positive and negative values for Energy separated so we can see exactly when we consume or deliver. I can do that in my Data Historion but it would be a nice feature.
What I would expect is that if the current is negative the energy consumed is reduced or it is not counted in same value/register but kept track of in another register.
In my case I measure what my home is consuming effectively and when the sun is shining the inverter(s) deliver to the grid. And we pay for the difference in some period.
I know that power meters we are using at my work (of brands Socomec and Janitza) keep the positive and negative values for Energy separated so we can see exactly when we consume or deliver. I can do that in my Data Historion but it would be a nice feature.