Mercedes-AMG GT XX: The Math Behind 40,075 km in 7.5 Days

Key Points

• Energy consumption equivalent to a decade: The Mercedes AMG GT XX consumed 20,000-23,000 kWh in 7.5 days, roughly 8 - 9 years of typical European driving or 4-5 years of US driving habits

• Relentless charging rhythm: The cars sustained ~300 km/h stints, estimated to have stopped every 11 laps (≈140 km) for around 38 charging sessions per day

• Operational reality vs. theoretical limits: While theoretically capable of 83% driving time, actual performance showed 69 - 75% driving time with increasing "rest periods" that signal towards the intense thermal and operational challenges

• Weather had zero impact: Despite temperatures reaching 34°C and wind speeds up to 35 km/h, as well as a short thunderstorm, the performance remained consistent, proving the technology's robustness under varying conditions

The Record That Changes the EV Conversation

The Mercedes AMG GT XX endurance run wasn't just about breaking records, it was about answering a fundamental question: can electric drivetrains and batteries handle the kind of abuse that would make internal combustion engines weep?

After crunching the numbers from 7.5 days of relentless punishment, the answer is both impressive and revealing. Two Mercedes AMG GT XX prototypes just consumed enough electricity to power your house for years, all while maintaining speeds that would get you arrested in most countries. Let's dive into what that actually means.

The Energy Appetite That Defies Belief

Let me explain, how much energy could have been used during this extraordinary run.

The Brutal Math

Speed Assumption: Mercedes mentioned 300 km/h four times in their press release. Three times as "constant 300 km/h" and once as "most of the time at 300 km/h." I used 300 km/h as the baseline.

Battery Capacity Assumption: Mercedes' EV portfolio (EQA, EQB, EQC, EQE, EQS, EQG and CLA EQ) ranges from 66.5 to 118 kWh usable, with most between 85-110 kWh. For this hyper EV, I estimated 115 kWh usable.

Energy Consumption: Based on the AMG One's 47.5 kWh/100km at Nürburgring and my Lotus Emeya S run, consumed around ~50 kWh/100km at 250 km/h (please don’t judge me - I will be uploading this review soon 😅), combined with the Mercedes AMG GT XX's 0.198 drag coefficient, I estimated following scenarios.

• Ideal conditions: 50 kWh/100 km = 20,038 kWh total

• Conservative estimate: 57 kWh/100 km = 22,850 kWh total

Putting This in Perspective

A typical European driver covers 12,500 km annually, consuming ~2,500 kWh per year. The Mercedes AMG GT XX demolished 8–9 years’ worth of normal driving energy in a single week. In the US, where people drive more, ca. 13,000 miles (20,800 km) and cars tend to be less efficient due to larger battery sizes, the preference for trucks, it still represents 4–5 years of typical consumption.

That’s not just impressive, it’s almost absurd and unbelievable.

When Theory Meets 300 km/h Reality

Mercedes loves highlighting that 850 kW charging capability. But the real question is: how much time did the Mercedes AMG GT XX actually spend charging versus driving at full tilt?

The Perfect World Scenario

If everything worked flawlessly, here’s how it would look:

• Battery capacity: ~115 kWh

• Charging from 10 – 80%: 80.5 kWh in 5.7 minutes at 850 kW

• Energy per lap: 7.2 kWh over 12.68 km

• Laps between charging: 11 laps, 27.7 min, traveling 138.7 km at 300 km/h

That math suggests 83% driving time, nearly 20 hours per day of pure speed.

What Actually Happened

Reality had other plans. Day 1 started strong with 75% driving time. Systems were fresh, and the team was efficient. But by Day 8, driving time dropped to 69%.

The data shows a consistent pattern: ~15% of each day went to charging (expected and if calculated at 850 kW charging), but another 10–17% were required, what I can only call mystery time. Either the car was driving slower than 300 km/h or the car was charging slower than 850 kW. This seems to be the brutal reality of pushing technology to its absolute limits.

The Hidden Overhead

That missing time likely included:

• Pre-cooling before charging sessions

• Extra thermal management between runs

• Charging taper when batteries overheated

• Safety checks and driver briefings

This is the stuff Mercedes doesn’t put in press releases. If you have any insights here, feel free to share.

Weather Threw Its Best Punches and Lost

One of the most surprising discoveries was how little Mother Nature could do to slow the Mercedes-AMG GT XX down.

Temperature Torture Test

Ambient temperatures ranged from 21°C to 34°C. Day 4 had both the highest temps and the strongest winds (35 km/h), yet the cars maintained 224 km/h average speed, identical to the best days (see chart below).

The Rain Surprise

Day 6 brought thunderstorms that should have disrupted everything. Instead, average speed improved from 215 km/h to 220.5 km/h. Perhaps rain cooled the batteries. I am not sure, but Mercedes AMG prototypes proved they could handle whatever Italy threw at them.

The Charging Rhythm of Champions

Let’s talk about the most underappreciated aspect of this run: the charging choreography.

38 Pit Stops Per Day

Every 11 laps, about 138 km, the cars pitted for energy. That meant 37–39 charging sessions per day, each lasting around six minutes including approach and exit.

Across the 8 days, that added up to nearly 280+ charging cycles. For perspective: I drove Volkswagen ID.5 for two years and covered nearly 39,000 km and I charged around 260 times. The Mercedes-AMG GT XX did it in a week.

Energy Consumption That Redefines “Brutal”

Here are the numbers that kept me awake at night:

Daily Appetite

• Conservative: ~3,100 kWh per day

• Ideal: ~2,700 kWh per day

Weekly Totals

• Conservative: 22,850 kWh

• Ideal: 20,050 kWh

No other EV test has ever cycled this much energy through battery cells this quickly. This wasn’t just about distance or speed. It was about proving that electric drivetrains and batteries can handle sustained abuse that would destroy combustion powertrains.

The Technology That Made It Possible

This run validated technologies that will define the next generation of Mercedes-AMG EVs:

Axial Flux Motors

• Three motors, delivering over 1,360 hp, sustained output across 3,177 laps

• 3x higher power density than radial motors, with smaller size and lower weight.

• Developed with Mercedes-owned UK specialist YASA

Robust Battery Design and Cooling

• New cylindrical NCMA cells (>300 Wh/kg energy density).

• Each of the 3,000+ cells is cooled individually using non-conductive oil.

• Direct cooling = stable performance under repeated charging and discharging cycles.

• 800 V architecture reduces cabling weight and enables faster charging.

Ultra-Fast Charging

• Consistent 850 kW charging rate, with 400 km range added in ~5 minutes.

• CCS2 connectors were used, highlighting AMG’s commitment to real-world standards, even if today’s public infrastructure can’t match this power yet.

• Alpitronic HYC 1000 was used with a 1000 kW CCS connector. During the launch phase, Phoenix Contact connecter was shown, but in the footage of track run, it looks like Amphenol. If you want to read in detail, I have written a dedicated article for it.

Why This Changes Everything

The Mercedes AMG GT XX run shifts the conversation from “Can EVs perform?” to “Who can keep up with it?”

This wasn’t about hitting one big number. It was about repeatability under extreme conditions, day after day, stop after stop, lap after lap.

When the Mercedes AMG.EA platform launches in 2026, it will bring technology proven under conditions tougher than most race series. That’s not marketing. That’s validated engineering.

The age of EV compromise is officially over. The new question is whether combustion engines can match this level of sustained, repeatable brutality.

Disclaimer

Analysis based on Mercedes-Benz data, Nardò weather records, and informed estimates where specific parameters weren’t disclosed. Battery capacity and consumption figures represent engineering estimates based on comparable high-performance vehicles and current Mercedes EV architecture.

That's it for today. If you found this useful, or have other feedback, please feel free to share, if my calculation and estimates were incorrect. I would be happy to discuss and change my results.

And if you want more of these grounded, real-world takes on EV infrastructure, charging, and pricing, make sure to follow me, and subscribe to my newsletter and also my YouTube channel.

Let's keep pushing the conversation forward.

Haseeb