The energy transition in Germany poses challenges, but two main issues are emerging with regard to power distribution. First, peaks occur on the system on days when high levels of wind and solar generation are injected. Second, increases in the use of electric heat pumps and electric transport are driving peak demand higher. Viewed through the lens of conventional grid planning, these developments would indicate that the distribution grid needs to be expanded. So-called “smart charging” of electric vehicles, however, can help mitigate these challenges.

Agora Verkehrswende, Agora Energiewende and Regulatory Assistance Project analysed research conducted by Navigant, Kompetenzzentrum Elektromobilität and RE-xpertise on distribution grid planning and the integration of electric vehicles. The authors drew four main conclusions.

The energy transition in the power distribution networks can be successful, even if all passenger vehicles are electrified. Grid-friendly, or “smart,” charging reduces the peak loads created when vehicles and electric heat pumps are charged simultaneously. It can also shift electricity consumption to times with abundant generation from solar photovoltaics and wind turbines.

Combining grid-friendly charging with the broader mobility transition can fund the energy transition in the electricity distribution grids by 2050, supplying 1.5 billion euros of annual investments in power lines and transformers. Without the mobility transition, annual investments of 2.1 billion euros would be needed to accommodate the 45 million electric cars expected to be on Germany’s roads, instead of 30 million with the mobility transition.

Electric mobility increases sales of electricity, while the overall investment needed for power lines and transformers does not increase. However, it is important that the participants in the mobility transition pay their fair share of grid fees.

Smart charging can be designed to ensure that users hardly notice any restrictions. We need secure information and communications technologies, incentives and, if necessary, obligatory managed charging. Precautionary indirect control, in the form of incentives for grid-friendly charging, should take precedence over direct control by the distribution grid operator.

Policymakers have an important role to play in making these opportunities a reality. In regulating managing charging, we recommend the following policies.

• Make grid-friendly managed charging of electrical vehicles the standard.
• Ensure that grid-friendly charging is normally voluntary and can be adjusted as needed by the consumer. Options for this are time-of-use tariffs and critical peak pricing at the charging point for specific time frames stipulated by the distribution network operator.
• Enable precise forecasts of the utilisation rates and possible optimisation of distribution networks. We can best achieve this through more secure, high quality hardware and software and can lead to the efficient use of flexibility resources to benefit consumers and accelerate the energy transition.
• Ensure that any direct control of charging processes by the distribution system operator is customer-friendly and only occurs when unavoidable.
• Implement less complex technical solutions during the ramp-up phase when the relevant information and communication technologies are not yet widely available, and ensure that equipment can be retrofitted with smart control technology. This will help avoid stranded assets.

The full study in German is available here.