Solar Production vs Solar Usage

I have a SolarEdge inverter that can charge my car. When I check the bubbles I see a negative number when my panels don’t produce enough power to offset the charging need of my car. At night my inverter is in standby and uses about 9 watts also a negative number. When I look at the cost things don’t add up. My usage is always a positive dollar amount and my production is a positive number. When I use power from the grid to charge my car with the inverter now the cost is negative. So what is correct? In my view the cost of power from the grid should be a negative number ( I am paying for it) My Solar production should be a positive number ( I am selling to the grid). So when the inverter is charging my car and takes power from the grid that is a negative for me I am buying that shows up correctly.

The problem is possibly that you have CT clamps on the solar and the inverter is drawing EV. It would likely be the same with batteries hooked to the SolarEdge.

The sense needs to get more sophisticated methods IMO

Is the EV charger wired to the leads on the inverter?

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Sounds like your CTs are in the wrong place for normal Sense operation. If you want to capture Solar Production, you have to catch the inverter current measurements upstream from the tap for the EV, though that may not be possible if you have some kind of dedicated tap within the inverter.

The CT clamps are correctly placed over the wires coming in from the ac disconnect into the main power center. The other CT clamps are over the two main service wires from the meter. The only difference is that there is no breaker in the power center connected to the solar wires. They are connected directly to the main service wire by a side tap.

But it sounds like your EV charging is directly connected to the inverter ?

The new SolarEdge inverter has direct connectivity to both batteries and EV chargers. This way the inverter can maximize DC solar power to charge both cars or batteries without converting to AC and experiencing loss.

The problem is that sense expects the power to flow in the direction of the panel. The inverter is supposed to “add” energy as far as sense is concerned. At night most inverter show a negative draw that is minimal when the inverter sleeps.

The inverter connected to an EV or battery is using energy instead of adding energy and sense is confused. Sense needs to update the platform to account for solar connections both adding and using energy similar to what the main utility clamps do.

It needs to be import/ export aware.

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Correct, The EV charger and the inverter are one unit. If I produce enough solar power the inverter will charge my car with sunlight. It is grid tied if there is not enough sun or at night it takes the utility power and sends it to the car through the inverter.

My car is not able to charge with DC, Prius Prime. The inverter sends AC to the car and the charger in the car will convert it back to DC to charge the battery.

In this case it sounds like Sense is actually reading correctly, when the inverter starts charging… Its now a charger and not an inverter. Negative values in the solar CTs is usage… Its going to throw your production numbers off but your overall grid usage will be correct. Im not sure that there is a way to see the values that your wanting to see.

My question was more at the dollar and cents values. You said negative values in the solar CT is usage. When you look at the usage side at the monitor I see positive numbers for cost. Positive numbers for production in wattages and cost but negative numbers when I charge. I think the green usage cost should be a negative number to reflect charging cost when I use my inverter.

Even without the EV charger… you still have to manually subtract the production off the usages to come out with your net useage/ production.

When you use your Inverter as a charger… and you see the neg values, it’s subtracting from your production. So if you made 100kWh this week then charged your car that took 65 kWh. It will show you produced 35 kWh. If your being billed by TOU then $ will be off. If you have a flat rate it will be correct