Infrastructure, network & energy

Wallbox & E-Mobility — charging with a plan.

A wallbox is quickly bought — it only makes sense in combination with photovoltaics, the incoming supply and the smart home. We plan on a manufacturer-independent basis, elektrofabrik installs.

PV surplusCharging from your own roof
Manufacturer-independentThe box follows the concept
KNX-integratedPart of the building's logic
One point of contactPlanning through to commissioning
Where we stand

A wallbox is not a socket — it is energy planning.

The whole installation, not an accessory

Charging power, the cross-section of the supply cable, circuit protection, position, registration with the network operator: a wallbox touches the entire electrical installation. We plan it as part of the electrical and energy planning for your house — including the honest question of how much charging power you actually need. The answer often turns out different from what the manufacturers' marketing promises.

The most interesting kilowatt hour comes off the roof

We plan wallboxes that align their charging power dynamically with the PV surplus: when the sun is out, the car charges — when the house is drawing a lot at that moment, the box turns itself down. That needs a suitable energy management system and the right metering at the incoming supply. With us both belong in the planning from the start, not added afterwards.

The second car is already allowed for

The incoming supply does not grow with you. Load management distributes the available power intelligently across several charging points and protects the connection from overload. We size supply cables and equipment so that the second charging point later only needs connecting — during shell construction that costs one more cable, afterwards it costs a rebuild.

Two stages

From a properly built charging point to an energy concept.

The baseline

Properly installed and registered

Every wallbox needs the groundwork: the right supply cable, protection with an RCD, registration with the network operator. Everyday work for us — including documentation and instruction.

  • Charging power honestly sized
  • Supply cable and RCD protection done properly
  • Registration with the network operator included
  • Installed by elektrofabrik
Our strength

Charging within the whole system

It gets interesting in the interplay: the box charges on solar power by preference, shares the incoming supply with the heat pump and the battery, and reports in on your KNX visualisation.

  • Dynamic charging on PV surplus
  • Load management for the second car
  • Priority between heat pump, battery and car
  • Charging status in the KNX visualisation
Wallbox & E-Mobility

A wallbox is not a device, it is a load concept.

The most common mistake is not the wrong wallbox but everything that comes before it: a cable that does not reach a charging flap on the other side of the vehicle, an incoming supply with no headroom, or a PV system feeding into the grid while the car beside it draws from it. We plan the charging point from the meter cabinet through to where the vehicle actually stands, and tie it into the same control system that holds the heat pump, the battery and the shading. Installation, groundworks and commissioning are carried out by our sister company elektrofabrik.

01

Position and where the vehicle stands

Before the first cable goes in, we settle where the vehicle actually stands: charging flap left or right, parked nose-in or reversed in, the cable length needed, room to manoeuvre, a second vehicle. Garage, carport, open parking space and an external wall each place different demands on the degree of protection, the mounting height and the cable routing.

02

Cable route and voltage drop

On large plots there can quickly be several dozen metres between the meter cabinet and the parking space. We calculate the voltage drop over the real route length rather than as the crow flies, and size the cross-section, the installation method, the burial depth and the transitions between main house, yard and outbuilding accordingly.

03

Circuit protection and residual current protection

Charging points produce a different fault pattern than a socket does. We establish whether the station brings DC residual current detection with it or whether that has to be added upstream, and we settle the cable protection, the selectivity and the space in the distribution board — at Villa Riyadh right through to a control cabinet prefabricated and shipped from Germany.

04

Incoming supply and load management

The honest question is not how fast the wallbox can charge, but what the incoming supply still has left in the evening. Static means: fixed limit. Dynamic means: a set of current transformers measures at the connection point and continuously releases whatever is spare — including defined behaviour if communication fails.

05

Several charging points

Two vehicles, visitors, later a third: we plan charging points as a group, with prioritisation, a fair split of the available power and defined behaviour when both plug in at once. Linked over master-slave or a backend — plus spare capacity in conduit and distribution board for later expansion.

06

PV surplus charging

Surplus charging is a control task, not a checkbox. We define the minimum charging current, the hysteresis and the waiting times so that the station does not start up every minute as clouds pass, and we settle the priority between vehicle, home battery and hot water. How generation really fluctuates we know from PV systems such as the SIDOL Lofts in Cologne.

07

Phase switching and charging windows

Without switching between single-phase and three-phase charging, the system stands still on a small surplus instead of charging slowly. Then there are the charging windows: a guaranteed minimum range by departure time, a night window for cheaper tariffs, priority for the vehicle that has to leave first in the morning.

08

Release and access control

Who may charge is not decided by the socket. Release by RFID card, app or a switch in the house, tied to the access control concept — at Detlef Steves' place in Moers the garage door, the door station and voice operation sit in one logic anyway. Guest charging stays limited in time and in power.

09

Billing and logging

As soon as company cars are involved, charging sessions have to be traceable: meter readings per charge, allocation to a user or a vehicle, exportable records for reimbursement by the employer. Which metering and which backend have to provide that we settle before the equipment is chosen — retrofitting here usually means replacing.

10

Energy management and visualisation

The charging point belongs in the same interface as everything else: current charging power, energy charged, PV share, release status — visible on the control panel in the house rather than in a fourth manufacturer app. We plan the data points that are really needed for it, and their route into the visualisation.

11

Interplay with the heat pump

The heat pump and the wallbox are the two largest single loads in the house and often want power at the same time. We settle priorities, blocking and release windows and the behaviour when grid power is reduced, so that in case of doubt the car charges more slowly and the heating keeps running.

12

Preparation during shell construction

The cheapest charging concept comes about during shell construction: conduit of sufficient nominal diameter to the parking space and the carport, a draw wire, generous bends, a spare conduit for the second charging point and a clean penetration through the floor slab or the basement wall. Afterwards every one of these points costs breaking open — the groundworks are carried out by elektrofabrik.

A charging point is only fully planned once it also works in the evening, when the heat pump, the kitchen and a second vehicle all want power at the same time.

Scope of work

What belongs to the charging infrastructure

Six building blocks we settle before a box is ordered.

01

Position & supply cable

Garage, carport or parking space — with a cross-section and a cable route that carries the second vehicle too.

02

Choice of box

Manufacturer-independent, to suit your energy concept: capable of surplus charging, capable of load management, able to be integrated into the smart home.

03

Energy management

Metering at the incoming supply, and the control that lets the PV system, the battery and the wallbox work together.

04

Load management

The available power distributed intelligently across several charging points — the incoming supply stays protected.

05

Coordination with the network operator

We handle the registration and the paperwork in the course of the planning — routine rather than bureaucracy.

06

KNX integration

Charging status, release by app or RFID, and an evaluation of the charging sessions in your visualisation.

How it runs

From the question to the charging point

1

Requirement & concept

We go through the driving profile, the vehicles and your expansion plans — and answer honestly how much charging power you actually need. Out of that comes the concept for today and for the second car.

2

Planning

Position, supply cable, circuit protection, energy management and how PV and battery are tied in are all settled before any components are ordered — coordinated with your electrical planning.

3

Registration

We take on the coordination with the network operator: preparing the paperwork, registering, and obtaining consent where higher charging powers need it. You need not deal with any of it.

4

Installation & commissioning

Our sister company elektrofabrik installs as a specialist electrical contractor, we commission, document and take you through it — one point of contact from beginning to end.

Bewiesen

Proven on site

01

SIDOL Lofts, Cologne

Around 645 PV modules in 23 strings as a tenant electricity scheme — energy engineering at scale, installed by elektrofabrik.

02

Period building, Düsseldorf-Oberkassel

A complete electrical installation in an existing building, from shading through to the smart office — the same discipline that produces properly built charging infrastructure.

03

100+ projects, 3 countries

From a detached house in North Rhine-Westphalia to a villa in Riyadh: planning depth that works on site — at your parking space too.

View all projects
Where we work

Wallbox & E-Mobilität in Cologne, Düsseldorf & North Rhine-Westphalia.

smartfabrik is a smart home planning practice based in Düsseldorf (Reisholzer Werftstr. 31A). We plan for private clients and companies in Cologne, Düsseldorf and across North Rhine-Westphalia — and, where wanted, nationwide and internationally. A selection of the places we have already planned and delivered in:

FAQ

Frequently asked questions.

Can the wallbox charge on PV surplus?

Yes, with the right equipment: an energy management system measures at the incoming supply how much solar power is left over and adjusts the charging power dynamically. What matters is a wallbox capable of surplus charging and suitable metering – not every box can do it. We plan the components so that the PV system, the battery and the vehicle work together properly.

Is 11 kW enough or do I need 22 kW?

For most households 11 kW is the sensible choice: overnight practically any battery is full, and registration with the network operator is simpler than the consent higher powers require. 22 kW is only worth it in special cases – for instance if the vehicle supports three-phase AC charging at full power at all. We work that through honestly with you.

Do I have to register the wallbox with the network operator?

Yes, private charging equipment is registered with the network operator; higher charging powers additionally require its consent. It sounds bureaucratic but it is routine – we prepare the paperwork and handle the coordination in the course of the planning. You need not deal with any of it, and the installation is properly registered from the outset.

Who installs the wallbox?

The installation belongs in the hands of a specialist electrical contractor – the supply cable, protection with an RCD and commissioning are not matters for DIY. With us our sister company elektrofabrik does that, the same firm that carries out our smart home projects. Planning and installation come from one source, including documentation and instruction.

Is the preparation worth it if I do not have an electric car yet?

Absolutely – and precisely now. In a new build the preparation costs little: a conduit to the garage or the parking space, a supply cable of sufficient cross-section, spare space in the distribution board. Afterwards the same thing means excavation or chasing. Our recommendation on every project: prepare the charging infrastructure, even if the vehicle is five years away.

Part of the living themeEnergy & efficiency
The first step

Prepare for charging before the car arrives.

In the first conversation we settle position, power and the PV connection — manufacturer-independent and with no sales pressure.

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