According to the 2017 Mobility in Germany study, Germany may have over 30% EVs in its overall vehicle stock by 2030. Expanding electric vehicle charging infrastructure is essential to electrifying transport, and larger vehicles such as buses and trucks need more high powered charging (HPC) infrastructure, which requires substantial capital investment. How can those investments meet customer needs at the lowest cost, while also remaining friendly to the grid and helping absorb variable renewable energy, like wind and solar?
To answer these questions, the Reiner Lemoine Institute (RLI) conducted a modeling and stakeholder interview study to determine the best options and layout for Berlin’s future HPC infrastructure. RLI undertook the study under the Sino-German Energy Transition project, as part of a larger effort to compare and contrast EV charging deployment in Germany and China.
In this article, we summarize the results of the analysis for high-power charging in Berlin. In a subsequent article, we will summarize the findings of our study of high-power charging in Shenzhen.
For Berlin, RLI’s analysis shows that depot charging works best for buses and many other fleets, while passenger cars and logistics vehicles will rely on a mix of depot and public charging of various configurations. Optimization of charging can enable a substantial reduction in investment costs while still meeting almost all charging needs.
Berlin’s public bus operator, BVG, aims to decarbonize its entire bus fleet by 2030. BVG prioritizes depot charging at low power levels to reduce peaks in power consumption, and thereby reduces cost for both peak loads and for charging station investments. Not only are low-power chargers cheaper, they also have lower personnel costs. HPC is most relevant for terminal stations (stops at the end of bus lines, as distinct from depots where buses return at night) and HPC at terminals is necessary for achieving full operational capability during the almost 10,000 bus trips per week in Berlin.
Various Berlin-region commercial fleet operators are also converting to electric vehicles through the WELMO facility (Wirtschaftsnahe Elektromobilität), a funding program coordinated by the Senate. Logistic fleets interviewed in this study also favor depot charging as it best fits their utilization patterns. However, several logistics fleet operators report their vehicles are operated by independent subcontractors that cannot rely on depot charging, and instead require public charging options.
Private passenger cars will access HPC under various specific use cases, depending on various degrees of access to residential and workplace charging. Private passenger vehicle HPC also depends on incentives and external factors, such as overall public charging pricing, as well as time-of-use pricing.
HPC load depends on design of charging incentives
Germany classifies charging according to seven use cases displayed below. Use Case 4 represents HPC at urban charging hubs or depots, typically at speeds up to 150 kW. Use Case 5 covers HPC at speeds as high as 350 kW at charging stations along major roads and highways. In contrast, Use Case 6 covers fast charging (DC or AC) at public charging stations at parking lots or shopping centers, while Use Case 7 covers slower public charging, either in parking lots or in on-street parking.
Public and private charging use cases defined by German government