Posted: 18th August 2026
What Megawatt Charging is and why it matters for HGV depot planning
The Megawatt Charging System (MCS) has been in development since 2018, but it remained a work in progress until early 2026, when the industry body behind it published the first formal technical standard for MCS. This sets out how the connectors should be built, what safety features they need, and how they manage heat, giving manufacturers a shared blueprint to design around. MCS is now a published standard that trucks and chargers can be built to, rather than a concept still being finalised.
What is the Megawatt Charging System (MCS)?
MCS is a new charging standard that allows a liquid cooled HGV battery, which can deliver up to 3.75 Megawatts (MW), to charge an electric truck or bus battery from 20% to 80% in under 30 minutes. This makes it ideal for a driver’s mandatory 45-minute break every 4.5 hours of driving as it allows a rest break to double up as a recharge window.
Originally introduced by CharIn in 2018, the industry alliance behind Combined Charging System (CCS), the MCS charging standard exists to serve battery electric vehicles (BEVs) designed for charging rates in excess of 1MW. MCS technology has been supported by Germany’s Federal Ministry of Transport, ABB, Tesla and others.
How does the MCS work?
The charger supplies high-power DC directly to the battery, without the limitations imposed by onboard AC conversion. The vehicle and charger communicate with each other to negotiate voltage and current limits along with other safety parameters while charging power is then controlled dynamically, adjusting based on battery temperature, state of charge, and overall system limits. Because the currents involved are so high, the hardware requires robust connectors, effective cooling, and heavy-duty cabling. This also means site infrastructure should provide very large electrical capacity, often requiring a dedicated substation.
Why MCS matters for HGV depot planning
MCS enables faster stop times for HGVs, allows vehicles to be out longer on the road, and allows each vehicle to spend less time using a charger at each depot. Electric HGVs draw far more power than vans or cars which changes depot design.
This affects grid capacity limits as most depots were not built for megawatt-scale demand, and local grid connections often cannot supply it without upgrades from the Distribution Network Operator.
On-site microgrids, paired with battery storage and sometimes solar generation, offer a way around this as they store energy off-peak and release it during high-demand charging windows, reducing dependence on constrained grid capacity. A well-designed microgrid can also act as a buffer against grid outages, protecting depot operations from unplanned downtime, and can reduce peak demand charges by spreading consumption more evenly across the day.
Depots also need a rethink of space and layout as megawatt chargers, cabling, and battery storage all need more room than standard AC or DC chargers. Planners also have to think about how vehicles move around the site, how long they stay parked, and the safety gaps needed around equipment. Managing all the cabling gets harder at this scale too because depots should leave room to grow, since fleets will likely add more electric vehicles beyond the first small batch.
Financial incentives, including government grants and financing, can offset capital costs, though eligibility varies by scheme. Some incentives target the charging infrastructure itself, while others support wider grid connection or renewable generation costs.
Several UK schemes help offset the cost of megawatt-scale depot charging including The Depot Charging Scheme which funds 70% of chargepoint and civil costs, up to £1 million per organisation, as part of a £170 million programme running to 2030.
The Zero Emission Truck Grant supports the cost of purchasing electric HGVs, reducing the total investment needed alongside infrastructure. Capital allowances, such as Full Expensing, let businesses deduct qualifying charging infrastructure costs from taxable profits, lowering the effective cost through tax treatment rather than direct grant funding. Eligibility and rates change frequently, so current terms should always be confirmed before relying on them.
What’s the difference between MCS and CCS?
CCS, which is capped in the hundreds of kilowatts, MCS enables charging power of up to 3.75 MW, using 3000 amps at 1250 volts DC. That means a Class 8 truck with a 600 kWh battery pack can go from 20 to 80 per cent within a standard 45-minute EU driver rest break, something CCS simply cannot achieve on a battery of that size.
MCS is a big step forward for electric HGVs, but it’s not something depots can simply plug in overnight. Preparing for megawatt scale charging means planning early: checking grid capacity, considering microgrids, rethinking site layout, and looking into the funding schemes available. Fleets that start this planning now will be in a stronger position as electric HGVs become more common on UK roads.
Get in touch with us if you’d like a site survey or a proper look at your fleet charging strategy.