P3 Charging Index
Comparison of the fast charging capability of various electric vehicles from a user’s perspective
However, from the customer’s perspective, a different picture emerges because a typical, real charging process today is essentially oriented towards two important questions for the electric vehicle driver:
The second question introduces another important parameter into the analysis which is rarely considered in many comparisons or tests; the actual consumption of the electric vehicle, which has a direct influence on the recharged range. This is because the recharged amount of energy is sufficient for a certain mileage depending on the vehicle’s consumption. The direct inclusion of the consumption leads to a significantly more realistic and ‘use case’ comparisons.
In order to include the most realistic consumption values of the individual electric vehicles in the calculation for the P3 Charging Index, surcharges based on the ADAC Ecotest were added to the respective WLTP consumption values. With the consumption and charging curves of the vehicles, now the recharged kilometers can be displayed over the time required for recharging. This already enables a more precise evaluation of the vehicles’ charging behavior, but it is not sufficient yet to directly compare electric vehicles without standardization.
The P3 Charging Index sets a standardization. As a quotient of actual recharged range in a time period of 20 minutes to a target value of 300 km recharged range, the P3 Charging Index defines the charging speed of vehicles and leads to a significantly higher comparability and therefore to more transparency regarding the real suitability for everyday use of electric vehicles on long distances.
𝑃3 𝐶ℎ𝑎𝑟𝑔𝑖𝑛𝑔 𝐼𝑛𝑑𝑒𝑥=𝐴𝑐𝑡𝑢𝑎𝑙 𝑟𝑒𝑐ℎ𝑎𝑟𝑔𝑒𝑑 𝑟𝑎𝑛𝑔𝑒 𝑖𝑛 20 𝑚𝑖𝑛𝑢𝑡𝑒𝑠1
300 𝑘𝑚
If the charging behavior of the vehicles is combined with the realistic consumption values and this charging behavior is standardized, comparative values are obtained for the respective vehicles. This comparative value should be equally representative for the unrestricted long-distance suitability of vehicles.
Should an electric vehicle reach the P3 Charging Index of 1.0, in practice the vehicle would be able to charge a range of 300 km in only 20 minutes. Such a vehicle could be driven for up to 600 km with a single charging stop of 20 minutes (if the battery is fully charged at the start). This form of standardization is also very practical as every typical long-distance driver would take a short break at least every 250-300 km anyway.
1 Charging process starts at 20 % SoC
None of the currently available electric vehicles in the market reaches the optimal value of 1.0. Still, the top 3 vehicles achieve already high values of more than 65 % of the maximum long-distance use value. In practice, this means that in individual cases the electric vehicle driver need must calculate with one or more charging stops on long-distance trips. It can be clearly seen that the newer vehicles of German manufacturers will probably be sorted high up in the field2. Electric vehicles of the earlier generations can be found in the lower field due to their lower charging capacities and (consumption) efficiency.
In order to secure full transparency, the recharged ranges after 10 and 30 minutes are also depicted.
2 Manufacturer specifications partly incomplete, thus complemented by expert estimates
In regular updates, we will publish new vehicles in the P3 Charging Index and also make updates of already introduced vehicles. So in the next release, besides the real values of the Porsche Taycan, an update of the Tesla Model 3 will certainly be available. Furthermore, vehicles like the Peugeot e208 or the Opel Corsa-e will be measured and will be rated with the corresponding index by then. With the help of the P3 Charging Index, we initially wanted to create transparency and traceability in an electric vehicle market that is still far too opaque in the discussion of rapid charging capability today.
Since not every electric vehicle will be launched on the market in the future with the claim to be suitable for long-distance travel and thus serve a different customer use case, we will extend the index to other vehicle segments. In addition, classic vehicle segments will be separated as soon as a correspondingly comparable number of vehicles exists – this is to avoid the compact class having to compare itself with the sports segment. We are already working to ensure that we compare vehicles that are more focused on urban areas with other target figures, but that we want to offer at least the same transparency and traceability.
The P3 Charging Index enables the comparison of actual and realistic charging performances of electric vehicles. It considers the maximum or average charging capacity of the vehicles as parameter, combines it with the overall efficiency of the respective vehicle and standardizes these key figures to a practical and driver-related use case.
The P3 Charging Index also makes a claim on the development of electric vehicles:
In the future, the development of vehicles should focus on a corresponding mix between charging performance and efficiency of the vehicle, because only the sum of both parameters defines the customer’s charging experience!