Street cabinet power sharing is a site design and control approach where a single roadside power cabinet (often an LV feeder cabinet or street-side distribution cabinet) supplies multiple EV charging points and dynamically allocates available electrical capacity between them. The goal is to install more on-street charge points without exceeding the cabinet’s import capacity, feeder limits, or local grid constraints.
In practice, the cabinet acts as a shared “power source” for several chargers, while load management ensures the combined load stays within a defined limit.
Why Street Cabinet Power Sharing Matters for On-Street Charging
On-street charging projects are often limited by:
– Restricted grid capacity in dense urban areas
– Cost and disruption of civil works and feeder upgrades
– Limited space for new substations or larger switchgear
– The need to roll out chargers quickly across many streets
Power sharing allows municipalities and operators to scale on-street deployments using existing infrastructure, while still maintaining safety and compliance.
How Street Cabinet Power Sharing Works
A typical system includes:
– A defined maximum demand limit for the street cabinet feeder
– Multiple charge points connected to that feeder (often AC chargers)
– A control method to allocate power across active sessions
Common control mechanisms include:
– Local controller in the cabinet that manages multiple chargers
– Charger-level load balancing coordinated by a master unit
– Backend-managed control via a platform (commonly using OCPP)
– Site-level metering and CT clamps measuring real-time load
When more vehicles plug in, each charger may reduce output so the total load stays under the cabinet limit. When fewer vehicles charge, available power is redistributed to increase individual charging power.
Typical Use Cases
Street cabinet power sharing is commonly used for:
– Residential curbside charging where many users charge overnight
– Lamp-post or bollard-style on-street chargers fed from a shared cabinet
– City center deployments where upgrading feeders is difficult
– Pilot zones that need rapid scale-up without heavy infrastructure changes
– Streets where parking bay turnover is predictable and dwell time is long
Benefits of Street Cabinet Power Sharing
– Enables more charge points from the same grid connection
– Reduces need for expensive grid upgrades and street works
– Improves rollout speed and flexibility for phased expansion
– Helps comply with feeder limits and prevent nuisance tripping
– Supports scalable public realm electrification plans
Design and Operational Considerations
Power sharing must be engineered to avoid poor user experience and safety issues:
– Define fair allocation logic (equal sharing, priority-based, time-based)
– Set minimum power thresholds to avoid “too slow to be useful” charging
– Consider diversity factors (not all bays charge at maximum simultaneously)
– Ensure accurate metering and clear billing if per-kWh billing is used
– Plan communications resilience (wired vs LTE) for coordinated control
– Coordinate protection devices so faults isolate only the affected branch
Limitations to Consider
– Individual charging speed may drop during peak occupancy
– Poor control logic can lead to inconsistent session performance
– Connectivity issues can disrupt coordinated sharing (depending on architecture)
– Cabinets may still require reinforcement if adoption grows beyond the planned diversity
Relationship to Load Management and Grid Constraints
Street cabinet power sharing is a specialized form of:
– Load management at feeder level
– Maximum site demand limit enforcement
– Peak shaving when combined with tariffs or, in some designs, local storage
It is often paired with detailed load profiling to size feeder limits appropriately and maximize utilization without compromising reliability.
Related Glossary Terms
On-street Charging
Kerbside Power Cabinets
Load Balancing
Load Management
Maximum Site Demand Limit
Import Capacity
Grid Capacity Assessment
Public Realm Electrification
OCPP