Power consumption increases when solar production increases – incorrect sensor setup?

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Hi all,

I’m seeing something odd in my Home Assistant setup and I’m hoping someone can help me understand what’s going wrong.

It appears that my reported power consumption / power usage increases as my solar production increases. In other words:
the more power my solar panels are generating, the higher my power consumption becomes — even though the actual loads in my house remain unchanged.

This doesn’t make sense to me, as I would expect solar production to reduce grid import, not to increase total power usage.

I guess i’m doing something wrong with the chosen grid power entities?

Naamloos
Naamloos915×1024 95.4 KB

thanks in advance

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In Home Assistant, the full energy equation for generators and consumers is

Solar + Import + Discharge = Consumption + Export + Charge

and HA solves this for the House Consumption Energy as

Consumption = Solar + (Import - Export) + (Discharge - Charge)

and if we know for any given period the five right-hand variables, HA can work out the consumption energy.

In terms of power, as the instantaneous rate of energy use, the Energy Dashboard works out much the same equation. Since the Grid can be either importing or exporting, but not both at the same time, and if you have a battery in the mix, the battery can be discharging or charging but again not both, HA uses

Load = Solar + Grid + Battery

where Grid = Import - Export, and Battery = Discharge - Charge if you have separate import/export and discharge/charge power sensors

In this Solar will always be positive, Grid and Battery will be positive for import/discharge towards the home, and negative for export/charge away from the home.

Since you don’t have a battery, the Power Equation for you reduces to

Load = Solar + Grid

Your Solar power sensor looks OK. The graph, as it is, indicates that you are not exporting anything, and Grid is zero all the time that solar power >= load.

Unlike the Energy settings, where we have two sensors, one for the energy imported from the grid [Grid consumption], and one for the energy exported to the grid [Return to grid] (and in your case you have two of each with different tariffs) the Power sensor setting normally has only one sensor. This has to show a +ve figure when importing power, and a -ve figure when exporting power.

For most of us, I think that our inverter / meter integration starts with just the basic power value, that shows as +/- depending on direction, and is exactly what the dashboard requires. This single sensor then has to be separated into power-in / power-out and then to energy-in / energy-out for the two energy sensors. If you only have one power in sensor and another power out sensor, then either they need to be combined [template sensor], or the second could be added to the Grid power sensor list, but note that the power out must be a negative value.

Hope that helps!

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