An electric car needs electricity and solar modules produce it. Actually, all the prerequisites are in place for the advertising promises to be possible. The charging station with photovoltaics on the roof charges the electric car. It is 100% independent, 100% eco, and 100% free. But in reality, it’s not that simple.
Basically, there is a direct current and alternating current which can be converted into each other. Solar power generator test winner (Solar Stromerzeuger Testsieger) generates direct voltage and thus direct current. Your power supply from the socket is an alternating current network, the voltage level changes 50x per second sinusoidally between 325V and -325V which results in the well-known 230V as an effective value. The battery in the e-vehicle generates a DC voltage and wants to be recharged by it.
In addition to the different types of current, there are also different voltage levels. You know the usual 230V from the household network and maybe the 400V from the three-phase network. With the batteries in electric cars, it now depends on how many cells are connected in parallel and in series. This results in a performance (engine power) and energy content (range) that depends on many factors.
As the icing on the cake, there are a wide variety of connector types and data exchange formats between the charging infrastructure and the e-vehicle. Almost all e-vehicles can be charged with the well-known SchuKo plugs, but then only with 230V and limited current. The Type 2 standard has been approved in Europe and the standards for Asia and the USA are about to be approved. However, practical tests have shown that the issue of connectors has not yet been satisfactorily resolved.
It doesn’t work without a power grid
It quickly becomes clear that a stabilized power grid is essential, even if advertising always tries to sell you otherwise and produces beautiful photos with solar modules on charging stations for electric cars. The DC voltage generated by the solar generators is converted and fed into the existing AC grid. At the same time, alternating current is drawn, which is converted to direct current and used to charge the e-car.
The ecological, self-sufficient effect can only be calculated on the electricity meter in the house. In the worst case, it even means that conventional baseload power plants have to be kept available and run with poorer efficiency in order to be able to compensate for potential dynamic feeders.