What was the objective?

I wanted to only use excess energy from the solar panels to charge the car.

This is the Windows app that monitors solar production and which can turn on/off car charging when the conditions are met.

Special settings only turn on when 3+ kW available only work within specified hours charge to the specified limit [95%] level before charge 92% range before charge 197 kms mileage 4,754 kms Battery capacity 42.5 kWh Final charge level after charge 95% Solar used 1.28 kWh Grid used "0.0000" Currently set to use only solar but a limited grid import of 700 W can be selected.

This created another problem, of remembering the mileage, battery level and range without making a mistake, when returning home to be able to input it in the app each time.

This was easily solved by creating a phone app to record the information in the car and send it to the Windows app.

The app allows the input of the details of the current car state when returning home The adjust buttons are set for the most common trip Once the information is input and saved it can be transmitted to the Windows app. It's also possible to turn on/off charging immediately by tapping the appropriate button And some other features were added

So how does the system turn on/off the charging?

By plugging the charger into a myStrom switch it's possible to turn it on/off remotely and to measure the current by sent to the car.

myStrom Switches

Swiss 13 A version

European 16 A version

Using Restful API commands the switches can be operated manually from the phone app or automatically from the Windows app.

 

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The phone app extensions.

	Enable/disable By double tapping turn off the automatic charging is disabled Useful when you leave as the Windows app needs to know not to turn on charging automatically When enabled it tells the app to take the current production and if sufficient to start charging. This bypasses the normal hysteresis, to cater for temporary fluctuations in load or cloud cover.
	Log View As the before and after charge levels etc. are recorded it was simple to add the location and to record trip history with stats per journey
	Read view Tap Read once Recall live charging state and progress any time
	Update Before leaving recall and update pre journey details Double tap Read This recalls from the Windows app what it registered as the change from charging. The phone app is now showing what the cars says, without the need for any specialised manufacturers apps.

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What charger is used?

The standard mains charger works with this system but for $100 a variable rate charger was acquired.

The benefit of this is it is possible to charge more slowly when there is less excess solar energy in winter months.
so it's also possible to charge over a greater period of the day

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How does it perform?

Actually the measurement of what is put in the car matches almost exactly what the car shows.

This means manufacturer apps which may be time limited or pay options, and generally don't give you as much flexibility, aren't necessary.

You can integrate your other facilities that depend on solar production to use as much as possible in the most effective way for your home