Volkswagen: Smart integration relieves the burden on electricity grids

Elli, a brand of the Volkswagen Group, and the Mitteldeutsche Netzgesellschaft Mitnetz Strom launched a nationwide pilot project for the smart integration of electric cars in the summer of 2022. The first results are now available. Around 20 drivers of Volkswagen models ID.3, ID.4 or ID.5 took part in the project between July and September 2022.

As the manufacturer explains in its press release, charging was carried out via private wall boxes and with the help of the Elli smart-charging app. An algorithm coordinated the charging processes between e-cars and grid operators in the background. Financial incentives optimised user behaviour. There were no losses in charging comfort or bottlenecks in the electricity grid. The idea behind this was to make e-cars part of the energy system.

This brings corresponding advantages, as the results of the pilot project and associated simulations by the Volkswagen subsidiary Elli and the grid operator Mitnetz Strom now show. The project showed that with the help of smart charging, existing grids can be better utilised and around 30 per cent of the CO2 emissions that would otherwise be produced during the generation of the charging current can be saved.

These effects are achieved through time synchronisation, so that more regionally produced green electricity can be used. In practice, wind power or photovoltaic plants are switched off because the grid cannot always fully absorb green electricity. In 2021 alone, around 6,000-gigawatt hours of renewably generated electricity had to be disconnected in Germany. This would have allowed around 2.4 million e-vehicles to run for a year.

 The incentive for participants in the project was directly linked to smart charging. Thanks to the variable grid charges, it was possible to reduce electricity costs for the year. Extrapolated, the front-runner saved over 70 euros per year. The charging management was correspondingly well accepted: 240 times, participants indicated so-called flexibility time windows for their charging processes. They agreed to postpone charging to suit the grid. At the end of the project, more than 80 per cent indicated that they were interested in continuing the trial. In addition, no restrictions on charging comfort were identified in the evaluation.

Equally exciting and important to know: No bottlenecks occurred in the local power grids during the three-month test phase. On the contrary, it was possible to connect five times as many electric cars to the grid with the project approach. The technology makes so-called grid interventions superfluous. If the local electricity grids are relieved in the course of this, the companies expect easier approvals of wall boxes for more households in the future.

Finally, VW informs that the pilot test took place nationwide. In the process, the organisers virtually recreated the infrastructure of a village in the vicinity of Halle, which Mitnetz Strom manages. With a low-voltage grid and around 50 households, most of them living in single-family homes, the general conditions there were similar to the situation in many German communities.