Power supply: Are the networks fit for the mobility turnaround?

Status: 11/25/2022 10:38 a.m

1.6 million electric cars are currently driving through Germany. But what if it’s going to be 15 million in just eight years? The energy supplier EnBW carried out the stress test for Baden-Württemberg.

For Matthias Rother from Wangen im Allgäu it was a “six in the lottery” – as one of 113 test persons he was allowed to test electric driving for six months free of charge for a study by Netze BW. Netze BW is the largest distribution network operator for electricity and gas in the EnBW Group and faces an equally great challenge: They have to equip the electricity network for the future.

Because if more and more e-cars will soon be on Germany’s roads, this will also increasingly burden the power supply. To ensure that this does not collapse, Netze BW examined in their study how electric mobility affects our power grids – with a focus on the private sector.

Network operators must keep the power grid stable

“The problem is the peaks in energy consumption, which can arise in particular from the high performance of the wall boxes for charging electric cars,” says Clemens von Walzel from EnBW, one of Germany’s largest electricity companies. Take a classic evening in winter: the lights are on, cooking is underway, the television and washing machine are on – and the electric car is connected after driving. “At some point, the transformers can reach their limits,” says von Walzel.

The grid operators are obliged to keep the voltage in the electricity grid the same. “If we have problems with voltage stability here due to e-mobility, we urgently need to ensure that the limits are not violated,” explains Markus Wunsch. His job at Netze BW is to integrate electric mobility into the grid.

Since the beginning of 2018, Netze BW has been carrying out various pilot projects, field tests and research projects for its study, which are intended to help optimize the power supply in the future. “We didn’t just want to do it on paper, we actually wanted to go out there under real conditions with real people,” says Wunsch. The study was intended to show what supply is required for customers in order to make the mobility turnaround possible.

What happens when everyone on a street switches to an electric car?

One of these “real people” was Norbert Simianer from Ostfildern near Stuttgart. The 75-year-old lives in the so-called “E-Mobility-Allee” on Belchenstrasse. There, Netze BW tested in a street, with eleven e-cars and a power circuit for around one and a half years, how e-mobility affects the power grid. To this end, ten households were equipped with electric cars and the charging infrastructure for their homes – electricity costs included. “It was important for us to get to know people’s charging behavior,” says Wunsch.

During the study, Simianer drove a small, compact electric car and was “very happy to do it”. The study has strengthened his confidence in electromobility: “I’m very positively surprised and would buy an electric car now. Our neighborhood has also become much closer now, and the study and the common topic have brought me into conversation with many.” Ostfildern’s Mayor Monika Bader also draws a positive conclusion about the pilot project: “It was very well received by the population, there were intensive and lively discussions, in a positive sense and out of curiosity. The project has led to great enthusiasm and acceptance for electromobility.”

Charging intelligently to relieve the power grid

An important finding from the study for Netze BW: Classic battery storage systems are inflexible. That’s why they want to rely primarily on intelligent charging in the future. This means that the power supply would be controlled remotely by the grid operator. In this way, customers can flexibly optimize their power consumption, as Wunsch explains: “We have found that most e-cars are connected to a charging point for much longer than is actually necessary. That is flexibility that is created here. And you can use it to also optimize charging processes, so that in principle we relieve the power grid and the vehicle is still fully charged the next morning.”

If the network operators were now allowed to operate intelligent charging, then the mobility turnaround would happen quickly enough: “Then we can now enable the infrastructure so that we can really get all the vehicles connected to the power grid.” However, there would still have to be a few prerequisites for this, such as the legal framework. In order for the network operator to be able to intelligently control the power supply, customers must agree and participate. And far too few are currently doing that, says Wunsch: “In practice, we see that charging stations are almost never registered for control by the network operator. This is becoming a major challenge with the increasing penetration of the networks by e-vehicles.”

That is why they want to strengthen the networks and make them intelligent. According to Wunsch, the aim must be to shape the legal framework in a pioneering way in order to reliably prevent regional network overloads. However, Wunsch is optimistic: The Federal Network Agency, as the responsible specialist authority, has already received comprehensive determination powers from the federal government on January 1, 2023 in order to implement the design of paragraph 14a EnWG, which is the issue here. “We will need a way to control the grid in order to ensure safe and stable grid operation.”

Electromobility must also be developed for climate goals

Even if you are faced with a big task, Wunsch is confident when it comes to the power supply and mobility transition: “It’s a very big challenge and I think it’s very important to emphasize that. For our climate goals, we also need an electromobility market that develops accordingly. It’s all very challenging for us, for our power grid. We can manage it, but we have some homework to do.”

And it is essential to think about the power supply, emphasizes von Walzel: “A lot of people are talking about renewable energies, talking about the energy turnaround. If you don’t upgrade the grid and don’t invest in the grid as well, the whole thing won’t work.”

source site