Mobile Rapid Charging: MIDA 120kW Movable Storage for Temporary Events

Quick Answer

A 120kW movable storage unit is a trailer-mounted battery energy storage system with integrated DC fast charging, typically 240–480kWh of LFP storage and 120kW of output, designed to deliver rapid charging at locations that have no permanent charging infrastructure — festivals, sports events, exhibitions, conferences, film sets, and pop-up retail sites. It arrives charged, energises in 15–30 minutes, and charges vehicles at rates that keep a queue moving rather than a trickle that never clears it. With dual or quad dispensing and dynamic power sharing, a single unit serves 20–35 vehicles per event day. It requires no grid connection — only a modest three-phase supply for replenishment between events.

Key Takeaways

• Temporary events need charging throughput, not installed capacity. A 120kW unit delivers roughly 1.5–2.5kWh per minute of session time, which is what actually clears a queue.
• Energy density sets the day’s capacity. 240–480kWh of storage supports 20–35 charge events per day when paired with dynamic power sharing across multiple dispensers.
• Silent and emissions-free at point of use. Unlike generator-based event charging, battery units create no noise, no exhaust, and no fuel logistics — decisive for venues with noise curfews and indoor footprints.
• Deployment is measured in minutes. No civil works, no permits for trenching, no utility application — the unit is towed in, positioned, and energised on arrival.
• The rental model pays back fastest. Event charging is billed per vehicle, per day, or as a sponsorship asset; high utilisation over a short season is precisely what movable storage is best suited to.

Why Events Are the Hardest Charging Problem to Solve

Every other charging scenario at least has the option of permanence. Depot charging is built once and amortised over a decade. Public hubs are installed where traffic justifies them. Roadside assistance operates within reach of fixed infrastructure.

Events have none of those advantages. Demand appears at a location for a few days, at a level that may exceed the site’s entire electrical capacity, and then disappears. The location is frequently a field, a park, a race circuit, or an exhibition hall with a connection designed for lighting and catering — not for dozens of vehicles pulling 100kW or more.

The constraints compound:

• No grid headroom. A stadium or exhibition centre may have a substantial supply, but it is fully committed to the event itself: stage power, catering, broadcast, temporary structures, and safety systems.
• No time for infrastructure. An event is planned in months, not years. Trenching, transformer upgrades, and utility applications are simply not available on that timeline.
• No tolerance for noise or emissions. Venues with residential neighbours, indoor halls, and evening programmes cannot host diesel generators running through the night.
• No second chance on driver experience. A queue that takes two hours to clear becomes a complaint, a social media post, and a lost sponsorship. The charging capability has to be credible on the first attempt.

Movable storage is the only format that satisfies all four constraints simultaneously. It brings the energy and the power to the location, needs almost nothing from the site, runs silently, and leaves without trace when the event ends.

What a 120kW Movable Storage Unit Contains

Three design decisions separate a professional event unit from a converted depot charger.

Output distribution. A single 120kW gun serves one vehicle well but creates a queue. Splitting 120kW across two dispensers with dynamic allocation means two vehicles charge simultaneously at 60kW each, or one at 120kW and one at 60kW depending on their requested profiles. Total energy delivery per hour rises, and perceived waiting time falls. It is the same dynamic power-sharing logic that lets fixed hubs maximise throughput without adding installed capacity.

Thermal capability. Event duty is aggressive: sustained sessions, high ambient temperatures, dust, and often no shade. Liquid-cooled power modules — such as the 40kW/60kW liquid-cooling power modules for DC EV charging stations — hold full output without derating where air-cooled hardware typically throttles back. On a 12-hour event day, that difference is measured in vehicles served.

Control and payment. An event charger is a public charger. Access control, session authentication, payment, and clear queue information are all part of the product. A unit that requires an operator to stand beside it managing each session is a labour cost, not an infrastructure solution.

Throughput: The Only Metric That Matters at an Event

Event organisers do not buy kilowatts; they buy vehicles served per hour without a queue. The table below shows what a 120kW unit with dynamic allocation realistically delivers.

Two principles emerge. First, usable energy — not peak power — sets the daily ceiling. A 480kWh unit with 85–90% usable depth of discharge delivers roughly 400kWh, which at 25kWh per event is around 16 sessions from storage alone, plus continuous replenishment if any site supply is available. Second, dynamic allocation raises throughput on the same energy, because two vehicles charging efficiently together use the unit’s capacity better than one vehicle charging alone while the second waits.

For multi-day events, the calculation changes again. A unit towed in at 90% state of charge that also draws 40–60kW from a site supply during the evening can sustain substantially higher daily throughput than its storage alone would suggest. The grid is used as a slow, steady replenishment source; the battery supplies the peaks — the same peak-shaving principle used at fixed charging hubs.

Deployment: From Arrival to First Session in Under an Hour

Compare this with the alternative: a permanent installation requires a site survey, an electrical design, a utility application, trenching, civil works, commissioning, and permits — typically 6–18 months. For an event with a planning horizon measured in weeks, there is no comparison to make.

At the end of the event, the process reverses in under an hour. The unit is towed away, leaving no excavation, no permanent cabling, and no remediation obligation — a requirement that many venues now write into their event agreements.

The Commercial Model: Rental, Sponsorship, and Hybrid

Temporary event charging is one of the few charging segments with genuinely high utilisation concentrated into short periods, which makes the economics unusually clear.

• Per-vehicle charging revenue. Event charging commands a premium rate because it removes range anxiety at a venue where no alternative exists. A unit serving 25 vehicles a day at premium pricing generates meaningful daily revenue.
• Day-rate rental to organisers. Many event organisers prefer to rent the capability outright, particularly for sponsor-funded charging zones. Day rates for a 120kW mobile unit are priced against the value of the amenity, not the cost of the electricity.
• Sponsorship and branding. Charging zones are highly visible, well-attended locations. Automakers, utilities, and energy retailers pay for presence in them, which can cover a substantial share of the unit’s operating cost.
• Fleet and shuttle support. Event operations run shuttle buses, staff vans, and logistics vehicles. Contracting to charge the event’s own fleet is predictable, high-utilisation work that continues through the whole event run.
• Resale and redeployment. A movable unit is an asset with a market. Between seasons it can serve construction sites, pop-up retail, film production, or roadside programmes, so it earns revenue more than 20 days a year.

The utilisation profile is what makes the model work. A fixed charger installed for a three-day festival is idle for 362 days; a movable unit that serves twelve events across a season, plus interim commercial work, has a fundamentally different return profile. Payback on a rental-fleet unit typically falls inside two to three seasons, with the asset retaining most of its value afterwards.

Safety, Compliance, and Public Operation

An event charger operates in public, among crowds, often with untrained users — a materially different environment from a depot. The requirements are therefore stricter:

1. Access control and authentication. RFID, app, or voucher-based session initiation, with the ability to restrict access to permitted vehicles or users where required.
2. Public safety architecture. Enclosed connectors, IP54 or better sealing, emergency stop, insulation monitoring, and clear physical separation between the charging zone and crowd circulation.
3. Transport and electrical certification. UN38.3 for battery transport, CE and IEC compliance for Europe, UL and ETL for North America, and documented vehicle-interface protection.
4. Temporary installation compliance. Ground securing rated for wind loading, documented cable management to eliminate trip hazards, and coordination with the event’s own safety plan and licensing authority.
5. Noise and emissions compliance. Battery units produce neither, which is why they satisfy venues and licensing conditions that exclude generator-based solutions outright.
6. Connectivity and monitoring. Real-time telemetry allows the operator to see state of charge, session status, and faults from a distance, and to plan replenishment before the unit runs low.

Certification quality has a commercial dimension too. Equipment that carries recognised marks clears venue insurance, event licensing, and sponsor compliance review markedly faster — the same dynamic visible in fixed infrastructure, where the protocol-complete 360kW liquid-cooled charging station with RFID, OCPP, and POS is specified precisely because its control and certification layer is pre-approved for public, paid operation.

Choosing the Right Event Configuration

1. Estimate vehicles needing charge, not vehicles attending. Typically 8–15% of EV-driving attendees use event charging, with higher take-up at venues far from public infrastructure.
2. Size storage for the day, power for the queue. Energy capacity sets the daily ceiling; output power sets how fast the queue clears. Under-specifying either produces a poor experience.
3. Specify multiple dispensing points with dynamic sharing. Throughput per kWh and perceived wait time both improve with two or more guns on one unit.
4. Confirm the replenishment path. Identify the site supply available overnight or between event days; even 40–60kW materially extends daily capacity across a multi-day event.
5. Require liquid-cooled hardware. Sustained event duty in summer conditions is exactly where air-cooled equipment derates.
6. Align the unit with your broader platform. Event units, roadside units, and depot chargers sharing one module platform and one OCPP backend give an operator a single training, spares, and management structure. The modular architecture behind the 480kW ultra-fast liquid-cooled DC charging station for motorways demonstrates how the same building blocks span temporary and permanent duty.
7. Plan the charging zone, not just the charger. Queue lanes, signage, marshalling, and a staffed or monitored presence determine the driver experience as much as the hardware does.

FAQ

1. How many vehicles can a 120kW movable storage unit charge in a day?
Typically 20–35 depending on storage capacity, session length, and whether the unit is replenished from a site supply between sessions. A 480kWh unit with dual dynamic dispensing handles the upper end of that range.

2. Does the unit need any grid connection at an event?
No. It arrives charged and operates entirely from its own battery. A three-phase supply is used only for replenishment and extends daily capacity on multi-day events.

3. How long does it take to set up at a venue?
Under two hours from arrival to first session, including positioning, securing, telematics checks, and site layout. No civil works or permits for installation are required.

4. Can it charge at 120kW on a single vehicle?
Yes, when configured as a single dispensing point. With two guns, dynamic allocation typically shares the 120kW, with the split determined by each vehicle’s requested charging profile and state of charge.

5. Is it suitable for indoor events?
Yes. Because it produces no exhaust emissions and minimal noise, a battery unit can be operated in or adjacent to enclosed spaces and in venues subject to noise restrictions — use cases closed to diesel generator solutions.

6. How is the unit transported between events?
It is towed on its own trailer or transported on a flatbed, depending on configuration. The transport frame, securing points, and battery certification (UN38.3) are designed for repeated relocation.

7. What happens if demand exceeds the unit’s capacity during an event?
The operator monitors state of charge through telematics and either replenishes from the site supply, rotates a second unit in, or manages access. Multi-unit deployments with a shared control platform allow vehicles to be directed to whichever unit has capacity.

Conclusion

Temporary events expose the fundamental mismatch between permanent charging infrastructure and demand that lasts three days. Movable storage resolves it by bringing energy and power to the site, energising in under two hours, running silently and emission-free, and leaving nothing behind. With 120kW of output, 240–480kWh of storage, dynamic power sharing across multiple dispensers, and a protocol-complete control plane with payment and telemetry, a single unit serves 20–35 vehicles a day at a location with no charging infrastructure whatsoever. For event organisers, rental operators, venues, and sponsors, that is not a temporary fix — it is the deployment model that makes rapid charging possible anywhere an event happens to be.

MIDA Power designs and manufactures movable storage and DC fast charging systems, liquid-cooled power modules, and integrated energy solutions for temporary and permanent deployments. Review the DC fast charging stations range or the MIDA commercial DC fast charging range for event, roadside, and depot applications, and contact MIDA via midapower.com for configuration and throughput modelling.