Straight forward grid tied solar - help with calculations for Home Assistant

First up, I think I have a pretty straight forward electrical set-up. In North America - have power coming in from the grid feeding an electrical panel. I also have a 13kW solar array that feeds into the panel as well.
Previously I was using the Emporia Vue. I switched to take advantage of the non-cloud access to data - and to integrate into Home Assistant. Here is what I’d like to output -

  1. Total Usage - what my house power needs are
  2. Net Usage - what my power company will read at the meter
  3. Solar power - what my panels are producing
    the next 2 are little trickier I think
  4. In From the Grid - grid power used (can be positive even if net usage is negative)
  5. Out to the Grid - power exported to the grid (can be positive even if net usage is positive)

The first step is setting up my CT sensors - here is my current set up - my big question is when should I use ‘allow negative’?

I know overeasy recommends PVoutput - and I have no problem using them - but I was hoping to set up the data on Iotawatt to then send to Home Assistant.

I’ll take a closer look at the problem tomorrow, but wanted to say that PVoutput is an inexpensive low overhead way to track all things solar, and there is Home Assistant integration for it. So it may be easiest to simply get the solar import and export via PVoutput.

On the mains because they will be negative when you produce more power than you use.

Be sure your solar has double checked. In the status above you are using 7,130 Watts (mains + solar). You are measuring usage of 6,135 so there is 995 Watts being used elsewhere.

I question you water-heater at 338W with PF .96. Is that a heat-pump water heater?

For the solar import and export, I’m still looking at how that works directly with HA. Maybe someone more familiar can help with that.

Thanks for the help! I did manage to set up a PVoutput account using the docs here.

And yes, that is a heat pump water heater. I do have the solar checked for double. As for the extra electric usage - I have a server rack setup, 2 fridges, and dehumidifier running - which would account for at least half of the missing power.

I look forward to any more info you can give in regards to the Home Assistant tie in - I already have it set up as a sensor within HA - just need to sort the math out on this end with my outputs.

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I have a somewhat similar setup to yourself except i am in Australia - this is what has worked for me

  1. We have 3 phase so i have a decidated IOTWATT for my main meterboard panels - where the grid comes in from the street

  2. Into this same board we have our 3 phase solar input

  3. From this same board i go out 3 phase to what we call a distribution board where all my house loads are.

So i have 3 clamps on the 3 phases in from the street
3 clamps on the input from the solar
3 clamps on the output to the house
(3 in reserve for when i shortly bring my battery system on board)

Here is a picture of the main screen - 5pm in Sydney in WInter so no solar left

And here is the setup screen

And the outputs screen


And the definition for one of my grid inputs

And one of my solar inputs as the inverters can suck power overnight

This basically works for me in Node Red as when i am feeding excess Solar to the grid i see the negative values in my dashboard whilst still seeing the +ve values for consumption from my main switchboard.