2025 Megawatt Charging System (MCS) Guide for Heavy-Duty EVs

What MCS is
MCS is a high-power DC charging system for heavy-duty EVs such as long-haul trucks and coaches. Current industry targets reference a voltage window up to ~1,250 V and current up to ~3,000 A, enabling multi-megawatt peak power. Early pilots have already shown 1 MW sessions on prototype long-haul trucks.

Why the industry needs it now
Driver-hours rules create natural charging windows: in the EU, a 45-minute break is required after 4.5 hours of driving; in the U.S., a 30-minute break is required after 8 hours of driving. The practical goal for MCS is to turn those mandated stops into meaningful refueling events without breaking route plans or depot schedules.

How it works

Power math. Power = Voltage × Current. At 1 MW, 30 minutes of charging delivers about 500 kWh (gross).

Battery window. A long-haul pack in market today is often ~540–600+ kWh installed. A 20–80% top-up on a 600 kWh usable pack equals ~360 kWh—well within what a 1 MW stop can deliver in half an hour when thermal limits and charge curves allow.

Real-world energy use. Heavy-duty e-trucks publicly tested at ~1.1 kWh/km (~1.77 kWh/mi). If ~460 kWh actually reaches the battery (illustrative ~92% DC-to-pack efficiency), a stop can recover roughly ~420 km (~260 mi) of range under favorable conditions.

Hardware & thermal. High current requires liquid-cooled cables and embedded temperature sensing (e.g., PT1000-class RTDs in the cable/contacts) so the handle stays safe and manageable for repeated manual use.

Communication. High-level vehicle–charger messaging authenticates the session, negotiates power, and carries metering and status data over higher-bandwidth links suited to fleet operations.

Standards and interoperability
Standards programs for the system (requirements), EVSE, connector & inlet, vehicle behavior, and communications are moving in step so trucks and chargers from different brands work together at scale. System-level guidance and connector definitions now align with public pilots and lab testing; additional revisions are expected as field data grows.

Milestones and progress

1 MW pilot charging publicly demonstrated on a prototype long-haul e-truck (2024).

Heavy-duty models publicly list MCS-class charge windows such as 20–80% in ~30 minutes as a design target for near-term rollouts.

Connector/inlet test programs instrument couplers with multi-point thermocouples to validate temperature rise and duty cycles at very high current.

Where MCS lands first

Freight corridors where a 30–45-minute stop must add hundreds of kilometers of range

Intercity coach hubs with tight turnarounds

Ports/logistics terminals with high daily energy throughput

Mines/construction and other duty cycles that cycle large packs continuously

What makes MCS different from car fast charging

Scale & duty cycle. Daily high-energy operations vs. occasional road-trip stops.

Connector & cooling. Couplers for very high currents employ liquid cooling and ergonomics that support frequent, safe hand connects and disconnects..

Ergonomics. Inlet position and handle design account for large-vehicle geometry and future automation.

Planning the site and the grid (worked examples)

Capacity & topology

Example A (four bays): If you plan 4×1 MW dispensers but expect ~0.6 simultaneity and 30-minute average dwell, diversified peak ~2.4 MW and nameplate peak 4 MW. Choose a transformer in the ~5 MVA class to leave headroom for auxiliaries and growth.

Ramp rates at megawatt levels are steep; DC bus or modular cabinet architectures help route power where it’s needed without oversizing every bay.

Storage & load management

A 1 MWh on-site battery can shave ~1 MW for one hour. In the four-bay example, storage can trim the grid tie from ~4 MW toward ~2.5–3 MW during overlapping 30-minute peaks, depending on control strategy.

Smart power management smooths current ramps, pre-conditions packs, and prioritizes imminent departures.

Civil, thermal, environmental

Shield coolant hoses and cable pathways, and reserve clear maintenance access around pumps and heat exchangers.

Specify ingress protection for dust, moisture, and road grime; plan ventilation for enclosures.

Use quick-swap subassemblies (handles, cable sections, seals, sensors) to keep uptime high.

Operations & uptime

Track both charger-side and vehicle-side fault codes; align spares & SLAs with route commitments.

Make interoperability tests part of commissioning; early fixes are months of uptime gained.

Safety & compliance highlights

Lockout, leakage/insulation monitoring, emergency-stop chains, and short-circuit energy handling are part of the spec family.

Thermal limits and temperature sensing in cables/connectors keep surface temperatures and contact temperatures within safe bounds for repeated use.

Ergonomic placement and handle geometry keep manual coupling practical at scale.

Procurement & rollout checklist

Vehicle compatibility: inlet location, voltage window, current limits, communication profiles supported now and via firmware

Power strategy: dispensers now, maximum per site later, and how cabinets/power blocks can be reconfigured

Cooling & service: coolant type, service intervals, field-replaceable modules

Cyber & billing: authentication methods, tariff options, secure update paths, metering class

Commissioning & QA: interop with target trucks, thermal & current-ramp tests, baseline KPIs (utilization, session efficiency, station availability)

FAQ
How fast is it in practice
Public pilots at ~1 MW have shown ~20–80% in about 30 minutes on long-haul prototypes, with actual time governed by pack size, temperature, and the vehicle’s charge curve.

Will passenger cars use MCS
No. MCS is tailored to heavy vehicles; cars continue with connectors and power levels optimized for smaller packs.

Is liquid cooling required
For hand-held cables at very high current, liquid cooling is the practical way to keep temperature and weight within safe limits.

What about the standards timeline
System, EVSE, coupler, vehicle-side, and communications documents are being published/updated in coordination with field experience and interop events; further revisions are expected as deployments grow.

Workersbee and MCS
Workersbee is a connector-focused R&D and manufacturing partner. We have initiated development of a reliable MCS connector engineered for high-current, liquid-cooled operation, ergonomic handling, and maintainability. Prototyping and validation are underway, with a targeted market launch in 2026.