Summary

A Mercedes-AMG GT XX prototype briefly exceeded 1,000 kW and maintained approximately 1 MW for around 2.5 minutes, utilizing a direct-cooled battery and a liquid-cooled CCS setup. This is a lab-grade result, but the message is practical: at very high power, thermal design and field serviceability decide real-world uptime more than headline voltage or cabinet ratings.

What happened

The demo paired an electrically non-conductive coolant circulating high-power cells with a liquid-cooled CCS cable and handle. That combination kept temperatures within limits long enough to sustain a megawatt-class window. In parallel, plans have been outlined for a 600 kW tier at public sites, with ultra-high-power lanes reserved for specific vehicles or duty cycles. In short, megawatt charging is moving from slides to hardware trials, while mainstream deployments will cluster in the 400–600 kW range.

What it really signals

Heat is the ceiling. Above a few hundred kilowatts, the weak link is rarely the cabinet nameplate; it is the thermal path from contact interface to handle, through the cable, into the pedestal. If any section runs hot, the system will derate or shut down. That is why sensors you can actually read at the curb, seals you can replace without a teardown, and clear torque specs for terminations are not “nice-to-haves.” They are revenue protection. Expect sites to stratify power: most bays run at 400–600 kW for consistent throughput, while a limited number of premium or fleet-dedicated lanes push higher current for short bursts.

Operator checklist (actionable points)

Thermal stack verification. Ask vendors for allowable temperature rise at the connector, cable, and pedestal—and the service intervals that keep those numbers steady under repeated sessions.

Liquid cooling above ~350 kW. Confirm coolant type, pump noise at the handle, and how quickly a field tech can swap wear items like O-rings and seals.

Power-sharing logic. Modular cabinets should dedicate full output to a single stall when needed and split dynamically at other times. This shapes actual wait times more than any peak number.

Grid math. Transformer sizing, feeder constraints, and demand charge exposure will determine if ultra-high-power lanes pay back. Run scenarios for average, peak, and holiday traffic.

Telemetry that matters. Prioritize temperature sensing at the handle and terminations, real-time derate visibility, and alarms that map to clear on-site actions.

Tech notes for engineers

AC vs DC is not the question at these levels; it is DC with aggressive thermal management. Contact pressure stability matters because micro-ohmic changes at the interface drive heat. Cable cross-section, coolant flow, and bend radius affect both resistance and operator ergonomics. The best systems maintain a steady current throughout the entire session, rather than oscillating to cool off. That stability is what shortens queues.

Where Workersbee fits

For operators piloting 400–600 kW today—and eyeing higher tiers—Workersbee focuses on connector thermals that hold power under load and on the small details that keep bays open. Our liquid-cooled CCS handles and cables emphasize accessible temperature sensing, replaceable seals, and documented field torque steps. Those elements cut repair time and make performance predictable.

For programs evaluating limited ultra-high-power lanes, we recommend a short site trial: measure temperature rise at the handle and terminations across back-to-back sessions, verify derate behavior, and log any service actions needed. Small, repeatable tests beat long spec sheets.

Megawatt headlines get attention, but sustained, profitable fast charging comes from steady thermal control and fast maintenance. Build for 400–600 kW as the workhorse, add ultra-high-power lanes where duty cycle and grid capacity justify them, and make serviceability a first-order requirement from day one.