Sunny times for your electromobility

PLENTICORE plus inverter with wallbox

A renewable way to charge your own electric car with self-generated solar power has become possible thanks to future-oriented key technology. The growing trend of generating your own power coupled with the desire for electromobility is known as 'sector coupling'. The combination of an inverter, such as the KOSTAL PLENTICORE plus, and your own wallbox makes this intelligent, safe and efficient.

A clever combination: charging with solar power

Driving an electric vehicle is fun – but charging it just as ecologically and economically is a challenge. Although it is possible to run a wallbox on conventional electricity from the public grid, using self-produced solar power instead is easier on your wallet and the environment.

It is therefore well worth connecting the home charging station for your electric car with the PV system’s inverter. By using renewable PV electricity, you can charge your own electric vehicle outside your own front door or at work – an environmentally friendly, flexible and convenient solution. 


  • 20/09/2021

How to combine a wallbox and inverter

New installation

If neither a photovoltaic system nor a charging station has yet been purchased, you can plan the ideal system with the installer. It is important that all components, such as solar modules, inverter, energy meter, battery storage and wallbox, are coordinated with one another.

The PV system with connected storage can then cover a large proportion of home consumption by means of solar power and supply the surplus solar energy via the wallbox to charge your electric car. The connected energy meter provides all the necessary information and ensures optimum wallbox operation.

Retrofitting a wallbox

If you already have your own PV system with inverter and storage, you can now cleverly add a wallbox. For perfect control, it must be possible for the new wallbox to be integrated into the existing PV system with the inverter. In addition to suitable interfaces, the charging power should be adjustable so that different charging modes are available for the wallbox and intelligent energy management is supported.

Retrofitting an inverter

If you already own an electric vehicle and wallbox and now want to add a PV system, it is important to check whether the existing wallbox can be combined with the new inverter.
This is the only way to ensure that the system consisting of wallbox and inverter can be intelligently controlled. If this is not the case, you should consider integrating a new wallbox into the complete system, which intelligently controls the charging processes of the electric vehicle with the inverter.

PLENTICORE plus: one device, many option

Hybrid inverter from KOSTAL
One inverter that already perfectly meets the varied requirements of sector coupling is the PLENTICORE plus. In the 3-10 kW power classes, it is a true multi-tasker that can intelligently control the PV system, a battery storage unit and a wallbox. The versatility of this all-rounder provides various options for connecting a charging station to the solar power system and thereby allowing you to use a large proportion of PV for charging.

With the PLENTICORE plus, a wallbox can be connected in a variety of ways depending on the initial situation.

Simple solar charging - perfect for a small power capacity

With so-called 'simple solar charging', the wallbox is connected to the PLENTICORE plus via a control line. The control signals from the inverter then flow directly into the wallbox’s switched input. In this way, the PLENTICORE plus operates in 'dynamic self-consumption control' mode, taking into account the user-defined switch-on and switch-off conditions.

Wallbox and simple solar charging

The switched output ensures that the signal is passed on when sufficient solar energy is available and can be fed in. The wallbox then starts to charge the electric vehicle and stops according to the switch-off conditions set up in the PLENTICORE plus menu. 

Most electric vehicles can be charged with a power of 1.4 kW or more, single-phase. If the wallbox has a control line input and has a single-phase output of up to 3.7 kW, then simple solar charging delivers good results with a high proportion of solar power – even with small PV systems.

'Simple solar charging' can be implemented with many entry-level models from various manufacturers. The PLENTICORE plus is the perfect match for a wide range of commercially available charging stations: 

  • KEBA b, c, x series
  • MENNEKES Amtron
  • ABL
  • Heidelberg
  • and many more.

Optimised solar charging with network connection

With 'optimised solar charging with network connection', the PLENTICORE plus inverter provides data via the Ethernet network using Modbus/TCP. The data exchange directly influences the wallbox operation and controls the current charging power, for example. If the KOSTAL Smart Energy Meter is integrated at the same time, any potential power surplus is also transferred to the grid, for instance.

Wallbox and optimised solar charging with network connection

Wallboxes with intelligent control can read out all data and thus regulate the charging power. The wallbox starts with a maximum possible charging process depending on the available PV energy generation and grid feed-in. In this mode, charging processes can start at 1.4 kW, for example, and be gradually adjusted automatically by the wallbox as long as there is surplus solar power available. To ensure this interaction, the PLENTICORE plus is connected into the existing network, with the wallbox, as a data source.

The advantages of 'optimised solar charging' are ease of use and the high cost-effectiveness of charging with solar power. At the same time, the network-based connection allows the largest possible proportion of solar power to be used through continuous charge adjustment. In addition, any potential overload of the house connection can be avoided as the charging power can be reduced early on – before an overload occurs.

If a storage unit (e.g. BYD Premium Battery Box) is connected to the PV system, electric vehicle charging can also be supported by the connected battery. This further increases the proportion of low-cost solar power used for charging up to the point where the car is charged with self-produced PV energy only.

'Optimised solar charging' is possible with various wallbox types. A stable network has to be set up for wallbox and inverter to be connected. The PLENTICORE plus is the perfect match for a wide range of commercially available charging stations:

  • Hardy Barth cPH1, cPμ1 mit eCB1
  • openWB

Optimised solar charging with control via external energy manager

With 'optimised solar charging via energy manager', an external energy manager is integrated into the system between the PLENTICORE plus inverter and the wallbox. The energy manager receives all relevant parameters for wallbox operation from the PLENTICORE plus via its data logging and reads them out via the Modbus/TCP interface.

Wallbox and optimised solar charging with control via external energy manager

When the KOSTAL Smart Energy Meter is integrated, information about the current feed-in power is also added. With this information, the external energy manager now actively controls the charging process via the wallbox.

The maximum charging power is determined by the energy manager. All parameters are configured via a web-based platform on the energy manager. In this system configuration, the charging current can also be dynamically controlled. All energy flows are visualised centrally via the energy manager. This creates precise operating times depending on the availability of PV power. 

The process of setting up 'optimised solar charging via energy manager' is more complex as more components are involved.

'Optimised solar charging via energy manager' is possible with the PLENTICORE plus and a wide range of commercially available charging stations and energy manager providers.

  • SolarLog with KEBA c-, x-serie
  • sonniQ with ABL, Mennekes, KEBA
  • Loxone with KEBA
  • gridX with ABL, Alfen, Heidelberg
  • KNX via BABtec Gateway

Combining the PLENTICORE plus with a wallbox provides a number of efficient operating modes. For high flexibility and great benefits, the PLENTICORE plus can be combined with commercially available charging stations from various manufacturers.

Find your suitable installer now.