Documentation

PV Surplus Charging (Solar Surplus Charging)

Surplus for solar surplus charging arises when you calculate the electricity generated by the PV system minus your household consumption. This surplus electricity is usually fed into the grid. With our wallbox and the integrated cFos Charging Manager, you have the option of charging your car only with the electricity generated that is not required for your household consumption.

The special feature of PV surplus charging is that only the electricity that is otherwise fed into the grid is used to charge the car and the car does not draw any further electricity from the grid. For this purpose, the cFos Charging Manager controls the charging current in such a way that the generation power of the solar system minus your household consumption is available to the car.

This requires at least one cFos Power Brain Wallbox and a meter that can measure the power fed into or drawn from the grid, as well as a PV system, of course. If you already have a wallbox from another manufacturer, you can use our Charging Manager Kit to realise PV surplus charging.

With the cFos Charging Manager, you define when and how solar energy is to be used. Using charging rules, you can, for example, set when PV surplus charging should be used or whether (e.g. in winter) additional mains supply should be used to charge the car. Of course, you can also configure enable-surplus charging using "Solar" charging rules. All charging rules can be switched on and off at any time.

Phase switching between single-phase and three-phase charging

Automatic phase switching

More information on surplus charging with the cFos Charging Manager

We offer optimised PV surplus loading

Charging power and mains supply for different charging methods

Here you can try out the effect of PV surplus charging for yourself. In comparison, the energy consumption when charging with simple solar rules (release excess charging) and maximum charging is displayed. Ideally, the red line should always be at zero, because then you are neither drawing electricity from the grid nor feeding it into the grid, but rather consuming the solar power optimally yourself. A certain feed-in is unavoidable, as the car can only charge from a minimum current of 6A. You can optimise this even further by switching phases.

  Solar
  Domestic consumption
  Shop
  Mains supply/feed-in