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Dynamic charging

I would like to charge my car directly from solar power. This means that I would like my car to dynamically charge based on the current solar generation. All other users may come off the grid. This is to prevent my solar generation inverting to the battery, inverting from the battery pack back to the car charger. I have a removed the battery from a tesla and am using 40kW as my home battery.

 It would be more practical and energy efficient if it were to directly charge during solar generation. (I dont drive this car during the day) This means adapting the charging state to whatever amount the solar is currently producing for eg. the solar installation generates 10kW, then the charger dynamically changes it to that value. When the car isn’t plugged in, solar generation can go to the battery or users based on the generation value.

Solar Power: 14kWp

Battery & Battery Inverters: Victron 

Solar inverters: 3x SMA - Sunny Boy

I know it is possible, I have seen someone do it but it was NDA solution. With C language & Arduino. I'm pretty sure it is possible using a MQTT server letting the charger know the current solar power & how much it can take..

I'm tempting to buy a DIY openevse charger but i'm not 100% sure I can use it to sort my problem.

Do any of you happen to know a solution that would fix my problem?

This is a feature of OpenEVSE. You just need to get your solar output in watts to MQTT. OpenEVSE will subscribe and follow along.

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@openevse, will it actually use up all the solar generation? Or will it wait untill other users for eg battery and household appliances are finished charging/being used?

It depends on the value that your energy monitoring system publishes.

OpenEVSE just tracks to the number of watts published. If you say 2000w is available, then OpenEVSE uses 2000 watts.

If your energy monitoring system just measures solar and publishes, then OpenEVSE will use all the solar regardless of household load.

If your system measures both solar and load and sends solar - load = available, then OpenEVSE will use available.

Here is some example code:

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