The Mercedes Vision EQXX has smashed its own efficiency record

The all-electric Mercedes Vision EQXX is really rather impressive. We already knew this after it completed a 1,008km single charge drive from Sindelfingen to Cassis followed by a second 1,202km jaunt from Untertürkheim to Silverstone, but now it has absolutely smashed its efficiency record on another mega road trip.

This time the journey was 1,010km (627.6 miles) from Riyadh, Saudi Arabia to the brand’s new showroom in Dubai. Yep, right across the Arabian Desert with ambient temperatures up to 34 degrees. Toasty.

Now, you’ll notice that’s not as far as the previous record run, but this time the EQXX arrived at its destination with 192 miles of range still left in its near 100kWh battery. That’s because across the 14h 42min trip (which included 1h 57min of stationary time at the border crossing and for driver swaps), the EQXX delivered a pretty remarkably 8.4 miles per kWh.

In general, most production EVs that we test here at TG record between 2.0 and 5.0 miles per kWh, and on its run to Silverstone the EQXX managed 7.5. And it wasn’t like the drivers in the desert were hanging around – this time the EQXX recorded an average speed of 42.7mph and a maximum of 87mph. The air con was on the whole time too with Merc’s close-to-production ‘multi-source heat pump’ working wonders to reduce the impact on energy efficiency.

The sun also gave Mercedes a chance to properly test the EQXX’s solar roof. Don’t get that opportunity often at Silverstone. We’re told the 117 solar cells on the roof allowed the EQXX to recoup 1.8kWh of power during the journey, with the car’s brain telling them where to park to align best with the sun. Clever.

The EQXX has now covered 14,503 miles in total during its life of testing, and we’re still hoping that the slippery design with its 0.17 drag coefficient translates into a limited run production car of some sort. Make it happen, Mercedes…