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## Solar PV Divert and Minimum Export

I'm trying to maintain a minimum export level before starting to charge the car using PV Divert. Is that possible? How does one interpret the Required PV power ratio setting as it is not clear how that affects things.

If I set 6A as minimum charge, does that mean I would need 1.1 x 6A of export before charging will start? Once more solar is available, the current will ramp up and consume all the excess trying to 'zero' out the grid export but instead of trying to zero things out, can I set like 1000W export always as the minimum?

Thanks!

Whatever logic you can dream up can be implemented. You will need a tool like Python or Node red.

Solar production - load = Excess

Excess - 1,000 (export minimum) = Available for charging.

Send Available for charging value to OpenEVSE and you are set.

The example for Tesla Powerwall does something similar. If the powerwall Battery level is below the target State of Charge, additional power is reserved for charging the Powerwall.

https://github.com/OpenEVSE/Solar_MQTT

``` if battery_soe < target_soe - 5: # Check Battery % reserve power to charge if below target
print ("Charging Powerwall " + str(battery_soe) + "% " + str(battery_power) + " watts")
if battery_power > 0:
excess_power = solar_power - battery_power - 1800
else:
excess_power = solar_power - 1800
if battery_soe > target_soe + 5: # Check Battery % alocate additional power to discharge if abeve target
print ("Discharging Powerwall" + str(battery_soe) + "% "+ str(battery_power) + " watts")
if battery_power > 0:
excess_power = solar_power - battery_power + 200
else:
excess_power = solar_power + 200
if battery_soe >= target_soe - 5 and battery_soe <= target_soe + 5: # Check Battery % reserve exact power to maintain if near target
print ("Maintaining Powerwall" + str(battery_soe) + "% " + str(battery_power) + " watts")
if battery_power > 0:
excess_power = solar_power - battery_power - baseline_load
else:

Got it. That's what I thought of later on in the night. Looking forward to getting some real excess solar generation.