Approximately 80 percent of the electric cars registered in Germany are charged at home. If these cars are parked in front of people’s own houses, installing a charging facility is not usually a problem. However, about 70 percent of households in Germany are located in buildings with multiple separate units, and most of these are rented. This makes it more difficult to provide these residents with charging infrastructure, and many people consider the availability of charging infrastructure an essential prerequisite for buying an electric car.

In order to include these potential users of electric cars who are living in multi-unit residential buildings in the ramp-up of electric mobility, it is important to address the challenges associated with deploying charging infrastructure. 

In addition to the legal framework, the study “Laden in Mehrparteienhäusern (Charging in multi-unit residential buildings)” analyzes the perspectives of the housing sector and residents of multi-unit buildings and derives recommendations for action. The Fraunhofer Institute for Systems and Innovation Research ISI led the study, which was part of the research accompanying the “ICT for Electric Mobility” technology program of the Federal Ministry of Research, Technology and Space (BMFTR). 

The legal framework is now simpler – but not simple enough

The authors’ first finding was a positive one: The legal framework conditions have improved. Among other things, it will no longer be necessary to obtain planning permission to install a charging point from 2026 in all German federal states. In addition, private charging points in multi-unit residential buildings are also likely to benefit greatly from the recent reductions in grid fees and electricity tax for bidirectional charging. At the same time, there are binding requirements for new buildings and renovations to prepare for and install charging facilities. However, installing charging infrastructure in multi-unit residential buildings remains complex and should be simplified according to the study’s authors.  

The housing sector needs stable conditions

The housing sector is a key player for the expansion of charging infrastructure. To get a better picture of this sector’s perspective, the authors conducted interviews with four municipal housing companies and three housing cooperatives from across Germany, each of which manages between 3,000 and 80,000 apartments. 

One of the housing sector’s main concerns is the uncertain future demand for electric cars and charging facilities, and the risk of spending money now on infrastructure that may not be used later. In addition, grid connection capacity usually only allows a limited number of cars to charge simultaneously. Load management can help here, but this incurs additional costs, as does the possible integration of a photovoltaic system. Charging infrastructure is often not (yet) economically viable for the housing sector. 

Furthermore, there are often not enough parking spaces for cars, especially in towns and cities. Converting parking spaces for conventional cars into parking spaces with charging facilities for electric cars harbors the potential for conflict due to the competition for parking. It is also not always clear whether and how the costs for parking spaces with charging facilities can be distributed fairly among those using them.

At the same time, the authors emphasize that the availability of charging infrastructure can make a location more attractive to tenants, especially in areas where the supply of housing exceeds demand. 

Charging solutions vary in their attractiveness for residents

If infrastructure is to be used successfully, it must be user-friendly and accepted by residents. To better understand their perspectives, the researchers conducted a representative survey of 1,472 residents of multi-unit residential buildings in Germany. 

On average, a private wall box is considered the most attractive charging option. However, residents are also open to other options, such as shared charging with people in the same building and charging at work. The only options considered less attractive are a neighborhood solution with no cost advantages and public charging.

Half of those taking part in the survey would like a charging point that is 100 meters or less from their home, but about 20 percent of those interviewed were also willing to cover 500 meters or more. This opens up different options for designing charging solutions.

The charging price is another important aspect. On average, the respondents are willing to pay just under €7 to charge their car for a 100-kilometer trip, which is roughly equivalent to the average electricity tariff for households. They pay an average of €11.50 for fuel.  

Reliable funding and a mix of different charging solutions are essential

The housing sector can act as an accelerator for the deployment of charging infrastructure. In particular, housing companies with numerous residential units at different locations could transfer solutions established at one location to other locations with similar characteristics, exploiting synergy effects and making the provision of infrastructure cost-efficient. 

For a rapid ramp-up of electric mobility, the study’s authors recommend that policymakers should provide reliable support and financial aid for deploying charging infrastructure to residents in multi-unit residential buildings. This approach could help to reduce uncertainties and improve the often still low economic efficiency of charging infrastructure. Policymakers should also consider different charging options, such as shared charging points in buildings, and further reduce the legal complexity as quickly as possible. 

Dr. Annegret Stephan, who led the project at Fraunhofer ISI, emphasizes: “There is no one-size-fits-all solution for residents charging cars in multi-unit residential buildings. To ensure efficient deployment, different options can be selected and combined. In addition to the local conditions on site, residents’ preferences are also crucial. And we shouldn’t forget that the availability of charging solutions can make a rental apartment more attractive.”