When Mercedes-Benz presented the VISION EQXX concept car at CES 2022 in Las Vegas, it was intended to be not just for a static display of design and new technologies. The fully engineered electric car was to be a real-world demonstrator of how EV technology could be advanced, with a target range of at least 1,000 kms.
First two runs exceed target
On the first publicised run in April 2022, the target range was achieved when a fully charged battery pack with more than 100 kWh of energy took the VISION EQXX from Sindelfingen in Germany to Cassis in France – a total of 1,008 kms. The average energy consumption was 8.7 kWh per 100 kms. For comparison, the production EQS 450+ consumes energy at a rate of 18.9 – 16.2 kWh/100 kms.
Following the first run, Mercedes-Benz engineers took it on another one, this time from Stuttgart to Silverstone across the English Channel in England. With no recharging along the way, the vehicle, which has 0.17 Cd aerodynamic efficiency, covered 1,202 kms, improving the average consumption to 8.3 kWh/100 kms.
New challenges in desert conditions
The two runs were done in the cooler conditions of Europe but EVs will be used all over the world in different climates with high and low temperatures. So for the third run, the development team decided to drive in hot desert conditions as a new test for the advanced technologies in the vehicle.
This took place in Saudi Arabia earlier in the month, and the conditions were certainly challenging, with a route profile encompassing busy city streets and open desert (on highways, of course). The starting point was the Mercedes-Benz Centre in Riyadh, Saudi Arabia, and the destination was 1,010 kms away in Dubai, UAE.
The VISION EQXX, which weighs 1,755 kgs, started its journey at 4:15 am and took 14 hours 42 minutes to arrive in Dubai. The route incorporated urban and sub-urban sections in Riyadh and Dubai with heavy traffic as well as long highway sections across the open desert. On arrival, there was still an available range of 309 kms shown on the display.
Even better efficiency on third run
In spite of the high temperatures (up to 34 degrees C.), the VISION EQXX beat its previous record efficiency with an average consumption of 7.4 kWh/100 kms. Using an industry-accepted conversion method, this figure is equivalent to 111 kms/litre for a vehicle with a combustion engine running on petrol.
Examining system performance
This third run allowed the engineers to examine system performance under extreme desert conditions. Of particular interest in the dry desert heat was the advanced thermal management, an intelligent on-demand system which keeps the electric drivetrain and cabin cool. The air conditioning system was operational during the trip with minimal negative impact on energy efficiency, thanks in part to the multi-source heat pump.
A further developed version of this heat pump is integrated into the Concept CLA Class unveiled at IAA Mobility 2023. This close-to-production concept previews the model family based on the Mercedes-Benz Modular Architecture and benefits from wide-ranging technology transfer from the VISION EQXX.
Testing the solar roof performance
The engineers also had the opportunity to examine closely the performance of the solar roof. The 117 solar cells are used to power many of the ancillaries, reducing the energy drain on the high-voltage system and further improving overall efficiency. On the drive to Dubai, the system harvested 1.8 kWh of solar energy, adding about 24 kms to overall range. For maximum solar yield during stops, the team parked the VISION EQXX in alignment with the sun using the solar information display (Tech View).
Also relevant for comparative analysis with previous test drives were the data gathered on the influence of wind and sun on efficiency. Other factors that will be studied were the solar temperature with measurements which even include the angle and direction of sunlight.
Besides the three publicised runs, over the past 2 years, the VISION EQXX has covered 23,340 kms of testing under a wide range of demanding real-life conditions.
“With an exceptional consumption of just 7.4 kWh/100 kms, the VISION EQXX continues to provide valuable data for ongoing development of advanced electric efficiency technologies. As expected, all systems performed perfectly in the desert conditions, handling challenges such as road surface finish and temperature as well as dust with ease. Further proof that electric drive is ready for global markets,” said Markus Schafer, Member of the Board of Management at Mercedes-Benz Group AG, Chief Technology Officer.