The quantity of charging stations in consideration

The quantity of charging stations in consideration - is it truly necessary?

As Germany aims to increase its fleet of electric vehicles and promote e-mobility, a new approach to charging infrastructure expansion is gaining traction. Professor Jutta Geldermann of the University of Duisburg-Essen has developed a mathematical model that shows 118 strategically placed charging points can cover 800 relevant locations for 500 electric vehicles in a needs-based and cost-effective manner.

Currently, Germany boasts nearly 170,000 public charging points for electric vehicles, but coverage in rural areas remains insufficient. With a target of 15 million electric cars by 2030, the number of charging points will need to increase significantly. As of now, there is approximately one charging point per 17 electric vehicles, compared to about one per 6 vehicles in the Netherlands, indicating a need for more rapid expansion, especially outside major cities.

Geldermann's model, which is a mixed-integer optimization model (Mixed Integer Programming) developed in Python, takes into account locations and dwell times of vehicles, costs for infrastructure and electricity, variable electricity prices, and charging behavior. It aims to reduce total costs per charging point by up to 50% compared to today's uncoordinated proliferation.

Controlled charging (e.g., when there is plenty of sun or wind) improves network load, and Geldermann argues that high-priced DC charging points may only be cost-effective in the long run where the throughput is high enough. The model is based on mobility data from the nationwide "Mobility in Germany" (MiD) study.

However, Geldermann's study has so far received little attention from the city of Essen, federal ministries, city utilities, car manufacturers, and charging service providers. To promote e-mobility effectively, there should be much more coordination between municipalities, city utilities, gas station operators, and service providers like EnBW or E.ON.

Some charging network operators have slowed down expansion due to low utilization of charging stations and the lack of economic viability of investments. Public charging points in Germany are currently used on average only 25 times a month, with some as little as once a month. 85% of users can charge at their workplace or nearby, while only 37% have a charging option near their home.

The Association of the Automotive Industry (VDA) and automobile clubs like the ADAC are calling for a significant and speedier expansion of public charging infrastructure for electric vehicles. However, Geldermann considers the VDA's demand for 1 million public charging points by 2030 to be ill-considered due to lack of clarity on where these charging points should be, how they will be utilized, and how user behavior will change.

Geldermann hopes for more cooperation between science, city utilities, car manufacturers, and charging service providers in the future. The Essen planning model for optimized charging infrastructure expansion can be applied to other cities and potentially the entire federal territory. With careful planning and coordination, Germany can ensure a cost-effective and efficient expansion of its charging infrastructure, paving the way for a successful transition to e-mobility.