Firstly, an electric car does not need to be charged that often. At least not if the vehicle, like its predecessors with combustion engines, is also moved. That's an average of just 22 kilometers per day in metropolitan regions. In small towns and villages, cars are moved an average of 44 km per day. But even that is not enough to drain a battery.
Secondly, if everyone charges at the same time, for example from 6pm after work, there could well be bottlenecks in the power grid. Could! But it doesn't have to! This is where grid-optimised charging comes into play. Grid-optimised charging means nothing other than that an e-vehicle is connected to its wallbox as normal after work, but the electricity only flows when the grid is ready and not in the red zone at its load limit. To ensure that this happens perfectly, it would make sense if in the future the car, wallbox and grid could communicate with each other as a matter of course. Technically, this would be possible via so-called smart meter gateways. But what is that actually? Behind the term is nothing more than an intelligent measurement and control device that enables smarter grid control than a blown fuse.
However, grid operators, wallbox producers and car manufacturers are not yet working together as intensively as they perhaps should in matters of smart meter gateways. For example, it is still not possible to automatically read charging profiles from all e-vehicles. And the current method of collecting grid status data means that a grid operator only knows that a fuse has blown somewhere. In the search for the answer as to where exactly this has happened, he is usually in the dark for a while. The possibility of disconnecting consumers from the grid in the event of an overload is also technically possible and is already being practiced today, especially with large industrial customers. However, if one day hundreds of thousands of e-vehicles are connected to the grid, smart meter gateways will have to be used much more closely than is the case today.
The fact that we at Mer can already enable grid-optimised charging today is due to a relatively small detour that we take when collecting data for our charging profiles: These can also be created based on fluctuations on the electricity price exchange. If the demand for electricity is low or the supply of electricity is particularly high, the price falls. If demand is high or the supply of electricity is low, the price rises. Based on the price barometer of the electricity price exchange, it is possible to decide when the charging of e-vehicles could lead to grid bottlenecks and when not. This all works without expensive grid expansion.
Nevertheless, our power grids must become smarter in the future. The safe charging of electric vehicles is only the first step towards a sustainable energy transition. The second step will be to be able to intelligently discharge e-vehicles so that they can be used as energy suppliers. A fully charged car battery contains enough electricity from renewable energies to supply a single-family household for a week.