Case study including user survey published
Rheinmetall Charging Kerb Ready for Regular Operation
The charging kerb enables charging of electric vehicles directly at the roadside.
Rheinmetall
After just over a year, Rheinmetall's charging kerb pilot project in Cologne has been successfully completed, proving the market readiness of the solution: Technical availability during the test period was over 99%, and users consistently gave positive feedback.
After just over a year, the pilot project for the charging kerb by Rheinmetall, in collaboration with TankE and the city of Cologne, has been completed. The focus was on testing a novel charging system for electric cars that is integrated directly into the kerb. The results of the accompanying user survey and technical evaluation are now available. The conclusion is overall positive - but despite all the enthusiasm, caution is also warranted.
Pilot project with limited scope - four charging points, around 100 responses
Between April 2024 and March 2025, four charging kerbs were installed at two locations in Cologne-Lindenthal. The aim was to evaluate the practicality and user acceptance of this previously unconventional charging infrastructure. According to the case study, a total of 100 people participated in the accompanying user survey - predominantly men with battery electric vehicles (BEV), with an average age of 48.
The number of responses is solid for an initial evaluation, but comparatively low to make generalised statements. The fact that the test locations were exclusively in urban residential environments also limits the transferability to other usage scenarios - such as in mixed-use neighbourhoods or more rural areas.
Charging Kerb in Practical Test: 10 Insights of Interest to EV Drivers
1. Charging directly at the kerb saves space and is unobtrusive
The charging kerb integrates the complete charging electronics into the form of a conventional kerb. This means there is no additional space requirement on pavements, no bollards are needed, and the cityscape remains largely unchanged.
2. High technical reliability in everyday use
During the one-year field test in Cologne, the system showed availability of over 99%. Technical problems occurred only sporadically and could be resolved within a day - evidence of high stability in everyday street use.
3. Very good acceptance among users
In a survey of 100 people, the charging kerb received an average rating of 4.38 out of 5 points. Particularly appreciated were the easy operation, accessibility from the street, and the harmonious integration into the surroundings.
4. Low-barrier use also for people with mobility impairments
Thanks to its low-ground construction and one-handed operation, the system is easily accessible - even for people with mobility impairments. A special insertion aid was additionally developed and successfully tested.
5. High utilisation - even without app visibility
Despite the lack of visibility in common charging apps (due to non-final calibration law approval), 2,829 valid charging processes were recorded - equivalent to 2.15 charging processes per day and charging point. The utilisation rate was a strong 65%.
6. Uncomplicated charging process - particularly intuitive
The opening of the charging socket, plugging in, and starting the charging process was consistently positively rated, especially the simple procedure with common methods (app, RFID, QR code) and the illuminated charging socket.
7. Comparison to classic charging stations mostly favours the charging kerb
In areas such as space requirement, sightlines, vandalism protection, and cityscape integration, the charging kerb performed significantly better than classic stations. The only disadvantage: visibility/findability, which can be solved through app integration.
8. Longer parking times in residential areas - users park continuously
In purely residential streets like Klosterstraße, the average charging duration was 9.2 hours - the charging point was often used as a parking space even after charging ended. This can be solved by limiting parking duration.
9. Cleanliness and lighting were optimised during the test
Early criticisms of dirt and insufficient lighting in the charging area were technically revised (e.g., non-stick coating, stronger LEDs) - this led to significantly better ratings after the adjustment.
10. Easy replacement in case of defects saves costs and time
The modular design allows defective charging units to be replaced in a few minutes without excavation work. This reduces service trips, downtime, and preserves the cityscape.
Technology in Test: Reliable, but Still with Room for Improvement
According to Rheinmetall, the technical availability of the charging points was over 99%. Disruptions occurred only sporadically and could mostly be resolved quickly. The modular design, which allows defective modules to be replaced, proved itself in practical tests. Even under winter conditions, the charging points functioned continuously, which speaks for the robustness of the solution.
However, in the first phase, there was criticism regarding the lighting and contamination of the charging socket - issues that were later improved through structural adjustments (e.g., non-stick coating, stronger LEDs). According to the study, the effect of these measures is reflected in improved ratings for cleanliness and user-friendliness.
User Feedback Shows High Satisfaction, but Also Gaps in Visibility
The average user rating was 4.38 out of 5 points. The system scored particularly well for its ease of use, the one-handed opening of the flap, and the appearance of the system. People with mobility impairments were also able to manage the charging process well - especially thanks to a specially developed insertion aid.
However, the low visibility of the charging points was criticised, as they were not listed in any common charging app (due to the pending calibration law approval). This led to limited findability in the street space, which, according to users, should be remedied in a later area operation through better markings and app integration.
Despite this limitation, 2,829 valid charging processes were documented - on average about 2.15 per day and charging point, with an average energy amount of 19 kWh per charging process. In total, around 50 MWh of energy was charged, which corresponds to a range requirement of about 120 kilometres per process. The determined utilisation of 65% is remarkable for a pilot project - but should not be overinterpreted given the limited number of locations.
Quick Overview of the Rheinmetall Charging Kerb
What is the charging kerb and why is it relevant for electromobility?
The charging kerb is a roadside integrated charging point for electric cars, where the charging electronics are built into a standard kerb. It enables charging directly at the roadside - without bollards, charging stations, or interventions in the pavement. Thus, it addresses the space shortage in densely populated cities.
How does kerbside charging work technically?
The charging flap can be activated via app, RFID, or QR code. The charging connection is flush with the ground and allows one-handed operation. Thanks to its modular design, the charging module can be quickly replaced in case of defects.
What experiences were made in the Cologne pilot project?
With over 2,800 charging processes and technical availability of over 99%, the system ran stably. Users rated comfort of use, accessibility, and appearance positively. However, visibility and app integration were identified as weaknesses.
What advantages does the charging kerb have over classic charging stations?
It saves space, integrates unobtrusively into the cityscape, and reduces trip hazards. Additionally, the need for protective bollards is eliminated. However, classic stations are more visible and currently more widespread.
What challenges exist for widespread use?
Currently, there is still a lack of calibration law-compliant approval and integration into public charging directories. Visibility in the street space also needs to be improved. The small sample size of the study also limits the significance.
What is the future of the charging kerb?
The tested charging points have been transferred to regular operation. Rheinmetall now offers the solution as a series product - also in pre-equipped variants (“hollow kerbs”) for later retrofitting. However, a larger area test is still pending.
Comparison to the classic charging station: Advantages in cityscape and accessibility
In the direct user evaluation, the charging kerb performed better in several points than classic charging stations - especially in terms of integration into the cityscape, protection against vandalism, accessibility, and space requirements on pavements. The ergonomic handling from the street was perceived as more pleasant by many, particularly because no additional bollards or wide bases are necessary.
However, one disadvantage remains compared to the traditional charging station: visibility. Here, both female and older user groups see a need for improvement - a challenge that Rheinmetall still needs to solve in regular operation.
What is important to users when charging - and how the kerb measures up
In a separate survey on general requirements for charging solutions, participants mainly mentioned:
- Cleanliness of the charging location
- Proximity to the place of stay
- Ease of use
- Safety (e.g. through lighting)
- Affordable electricity price
The charging kerb scored well on most of these criteria - particularly in terms of ease of use and proximity to the place of residence. However, a price evaluation was not planned in the project context.
Cautious outlook: Market readiness within reach - widespread expansion still open
After the completion of the pilot project, the charging points were transferred to regular operation. Rheinmetall considers the solution to be ready for series production and is offering it as a product with immediate effect. In the future, so-called hollow kerbs are also to be installed as infrastructure reserves, which can be retrofitted with little structural effort as demand increases.
For municipalities, the approach potentially offers advantages: easy integration into existing streets, low space requirements, lower installation and maintenance costs. However, many questions regarding rollout, standardisation, app integration, and legal approval are still open or in preparation.
The results from Cologne show: The charging kerb is a functional approach for public, space-saving charging in the street. User experiences are mostly positive, particularly regarding everyday usability, design integration, and handling. Nevertheless, the study with 100 participants is only a first step - further technical developments and a robust practical test on a larger scale are necessary for widespread use.
This article was first published
at all-electronics.de
