Home Assistant is all about the Home. The Energy Dashboard (and the power chart) is designed to show how much energy / power the home is using (and where it comes from and goes to).
The total energy / power equation must balance, with the sum of all generators (sources) matching the sum of all consumers. Hence
Solar + Import + Discharge = Consumption + Export + Charge
and HA solves this for the Consumption (energy used) as
Consumption (energy) = Solar + Import + Discharge - Export - Charge
Where, for the energy all of the five required figures are positive quantities.
In the Power Chart, the dashboard wants just a single grid and battery power sensor, hence
Load (power) = Solar + (Import - Export) + (Discharge - Charge)
and where
Grid = (Import - Export) as the grid power sensor, and
Battery = (Discharge - Charge) as the battery power sensor.
A singular power sensor must therefore show +ve for Import and for Discharge [toward the house], and -ve for Export and for Charge [returned away from the house].
Naturally, grid and battery can physically only be in one direction, so Grid / Battery are either +ve or -ve at any particular moment. This means that solar power is always plotted above the time axis, grid is stacked (added) above if +ve import or shown below if -ve export, and battery is stacked above if +ve discharge or stacked below if -ve charge.
The stacked sum above the axis is the total of all source power [solar, import, discharge], and the stacked sum below the sum of all ‘returned’ power going back to grid / battery store. The consumption dotted line is the numerical sum of the three solar+grid+battery and is the resultant instantaneous power going to the home.
You can see from my example graph above, that at 10:17 on the 7th January this year, I had 180 W solar power, 410 W imported from grid, and 270 W charging the battery (-ve), leaving 180+410-270 = 320 W as house load.
The power graph shows a lot of information - for this day my solar power was directed to charge the battery, with the house load always coming from the grid, until the battery stopped charging. The area under the dotted line to the axis shows the different home power sources - either all grid, or half grid and half solar (and would also show battery discharge source if applicable). Any area appearing above the dotted line shows that some solar/grid/battery power is going elsewhere, to the battery/grid, and the area below the axis shows what this ‘returned’ power is and where it is going (battery or grid).
Looking at your graph I suggest that your battery sensor is inverted, and possibly also your grid sensor. I also assume that you either limit your solar generation to match the house load, or run a heat-store to dump excess solar to something (other than your battery).
