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Energy import example

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The so called "Energy import" is inspired by PVOutput energy import chart.

If the generated power (Net power) is greater than the consumption, the energy import is no more raising.




PVLng adoption


The interesting part is the red Energy import spline, which stops at 7:20 by 2820 Wh. This means, no energy import, only export. Import restarts at 17:50.

Please note:

  • Arrange the channels according their units to the axes!


Let's start with the meter channels for the areas.

I decided to put all watt channels on the left and all kilo watt hour channels on the right axis.

All calculation is based on these real channels

  • PAC [W] inverter power
  • E-Total [Wh] inverter production
  • Power usage [W] from S0 impulses

Lets prepare the calculated channels.

Power balance


This is a full differentiator channel to get also negative values.


For good-bad look the negative values will be shown in red.

Energy Import

For this channel we need a Proxy models#SensorToMeter channel, which transforms our power usage into an energy usage. (Factor is here set to 1000 to get kilo watt hours from watts.)


The energy import channel is based on the Import / Export channel type.


We define here a negative cost per kilo watt hours to see later the amount consumed. (We pay here 23.44 cent per kilo watt hour == 0.2344 €)

Internal consumption

Internal consumption is simply the difference between overall energy usage and energy import.


We get here 16.74 cent per internally used kilo watt hour == 0.1674 €

Energy export




  • We have consumed 2.899 kilo watt hours of our self produced energy, bought 8.767 kilo watt hours and have a win of € 0.78 this day!
  • We have also exported 9.434 kilo watt hours for € 2.34
  • The Amount column will only be filled for meter channels.
  • The Cost column will only be filled for meter channels with costs defined.