What Is Load Management in Electric Vehicle Charging?
When you want to charge several electric vehicles at the same time, the thing that often falls short is not the charger but the building's electrical capacity. The grid connection of an apartment building, a workplace or a shopping-mall car park is limited; if every charger runs at full power simultaneously, the main fuse trips or the transformer is overloaded. This is exactly the problem that load management solves.
What is load management?
Load management is a control method that intelligently distributes power to multiple chargers without exceeding a site's available electrical capacity. The system continuously monitors the total power being drawn and balances it by raising or lowering the current (amperage) delivered by the chargers. This way, even as the number of vehicles charging at once increases, total consumption stays within the site's safe limit.
In short, load management is the job of 'sharing out power'. When a single vehicle is charging it can be given more power; when a second or third vehicle connects to the same line, the system automatically shares the power among them. No vehicle draws enough load to put the grid at risk.
Why is it needed? The relationship between power (kW) and capacity
kW expresses the power, that is the speed, of charging; kWh is the amount of energy transferred to the vehicle. A site's grid connection is also limited, measured in kW (or kVA). For example, even a single 22 kW AC wallbox can use a significant portion of a small building's available capacity.
When multiple charging points are installed, the maths quickly gets tougher. If five 22 kW wallboxes run at full power at the same time, they create a demand of 110 kW. Most apartment buildings or small businesses cannot handle this with their grid connection. Without load management, the only option would be an expensive connection-power upgrade or a transformer investment. Thanks to smart distribution, the existing infrastructure is preserved.
- Prevents the main fuse from tripping and avoids power outages.
- Reduces the need for a costly connection-power upgrade or transformer investment.
- Allows more charging points to be installed on the same infrastructure.
- Ensures all vehicles charge safely and in a balanced way.
- Avoids the extra electricity costs caused by exceeding your demand limit.
What is static load balancing?
Static load balancing is the method in which the total power allocated to the chargers is capped at a fixed (predefined) ceiling. For example, a 40 kW budget is defined for the installation; the system shares this 40 kW among the connected vehicles and never exceeds this limit.
In this approach, the chargers do not know how much power the rest of the building (lifts, lighting, air conditioning, etc.) is drawing. The budget allocated to charging is set safely and low, assuming the moment when the building's other loads are at their peak. Static load balancing is simple to install and requires no additional meter; however, because it cannot use spare capacity that is available on the grid, its efficiency is limited.
What is dynamic load balancing?
Dynamic load balancing is a more advanced method that, through a current/energy meter (smart meter) placed at the site's main incoming supply, continuously reads the building's actual real-time consumption and passes the remaining spare capacity to the chargers in real time.
For example, during the day, while air conditioning and machinery are running at a workplace, less power is allocated to charging; in the evening, when the loads drop, far more power is opened up to the same charging points. When total consumption approaches the connection limit, the system automatically reduces the charging current, and raises it again when capacity frees up. This way the existing infrastructure is used in the most efficient way for both the building and the vehicles.
Static load balancing allocates a fixed budget to charging; dynamic load balancing reads the building's instantaneous consumption and distributes the remaining spare capacity to charging in real time.
What is phase balancing?
In most corporate and large facilities in Türkiye, electricity is supplied over three phases (three-phase). Some vehicles and chargers draw power from a single phase (single-phase) while others use all three phases at once. If the charging loads are distributed unevenly across the phases, one phase can become overloaded while the others sit idle; this leads to fuses tripping and inefficient use of capacity.
Phase balancing distributes the charging load as evenly as possible across the three phases, ensuring that no single phase is overloaded. Smart load management systems optimise the distribution by taking into account which vehicle is drawing from which phase, helping to get maximum benefit from the available capacity.
The role of OCPP and CSMS in load management
In multi-device installations, load management needs a central brain. OCPP (Open Charge Point Protocol) is an open communication standard spoken between the chargers and the central management software (CSMS). The CSMS sees the status of all stations, sets the current limits, and sends the commands to share power among the devices.
OCPP-compatible devices can thus be monitored remotely, grouped, and managed with smart charging profiles. An administrator can centrally set up scenarios such as prioritising charging during the night tariff, reducing power at certain hours, or defining different limits for vehicle groups. Bemis's OCPP-compatible models are designed to suit these kinds of remote and smart management scenarios.
Local and cloud-based load management
Load management can operate at two layers. In local load management, the devices communicate with one another within the same site network to share power; balancing continues even if the internet goes down. In cloud/CSMS-based management, the central software takes on broader functions such as billing, reporting and remote control. Robust installations usually use these two layers together.
Example scenario: Many vehicles on a limited connection power
There is a desire to install 6 units of 11 kW wallboxes in an apartment building's car park, but the power budget the building can allocate to charging is only 33 kW. Without load management, if all 6 devices ran at full power at once they would create a demand of 66 kW, doubling the building's capacity; this is not possible.
With dynamic load management, the scenario works like this: If only 1 vehicle is connected late at night, it can be given almost the full 11 kW. When 3 vehicles are connected at the same time, 33 kW is divided by three, giving each vehicle roughly 11 kW. If 6 vehicles connect at once, the system opens up about 5.5 kW on average to each; the vehicles charge a little more slowly but all safely and simultaneously. The 33 kW limit is never exceeded at any moment. As vehicles finish charging and leave, the freed-up capacity is automatically transferred to the vehicles still charging.
Which installations require load management?
- Apartment and residential-complex car parks: Places where many units share a limited common connection.
- Workplace and office car parks: Installations where employees' vehicles charge together during the day.
- Shopping malls, hotels and commercial car parks: Areas with high vehicle traffic and variable demand.
- Fleet charging depots: Depots where many vehicles are charged together at specific hours.
- All multi-point installations on a single connection: Any place where total demand could exceed the limit.
In a standalone villa installation with a single wallbox, load management is not mandatory; however, in any scenario where two or more charging points share the same connection, load management is in practice a necessity.
Choosing the right equipment
To benefit from load management, the chargers must be models with communication capability that can change their current setting remotely. Bemis's Type 2 AC wallbox products (7.4-22 kW) and CCS2 DC fast-charging units offer options suitable for multi-device installations and smart charging scenarios; OCPP-compatible models can be integrated into central management and dynamic balancing setups.
Bursa-based domestic manufacturer Bemis E-V Charge, with its CE and IP65-IP66 protected equipment, supports projects at different scales from apartment buildings to fleets. The healthiest approach for choosing the right device, cable and architecture is to plan the installation's power budget and vehicle count from the outset.
Summary
Load management is the key to safely charging multiple vehicles without exceeding a limited electrical capacity. Static balancing allocates a fixed ceiling to charging, while dynamic balancing reads the building's actual consumption and uses spare capacity in real time. Together with phase balancing and OCPP/CSMS management, multi-device installations become scalable without expensive infrastructure investment.
Explore OCPP-compatible wallbox and DC charging solutions for your apartment, workplace or fleet installation; with the right load management architecture, use your existing infrastructure in the most efficient way.
Explore AC Wallbox productsFrequently Asked Questions
What is load management in EV charging?
Load management is a control system that intelligently distributes power to multiple chargers without exceeding a site's available electrical capacity. The system continuously monitors the total power drawn from the main supply and balances it by automatically raising and lowering the current (amperage) delivered by the chargers. When one vehicle is connected it is given more power; when a second and third vehicle are added, the power is shared among them. This way, even as the number of vehicles charging at once increases, total consumption stays within the safe limit of the building's connection power, and there is no fuse tripping, transformer overload or power outage.
What is the difference between static and dynamic load balancing?
Static load balancing allocates charging a predefined fixed power budget (for example 40 kW) and does not take into account what the rest of the building is drawing at that moment; for this reason the budget is kept low and safe, and spare capacity cannot be used. Dynamic load balancing, on the other hand, reads the building's actual real-time consumption via a smart meter placed at the main incoming supply and distributes the remaining spare capacity to charging in real time. In the evening, when other loads drop, more power is opened up to charging, and when consumption approaches the limit it is automatically reduced. In the end, the dynamic method uses the existing infrastructure far more efficiently.
Why is load management necessary in apartment and workplace installations?
The connection power of apartment, residential-complex and workplace car parks is limited, and this power is shared with loads such as lifts, lighting and air conditioning. If multiple chargers run at full power at the same time, total demand exceeds capacity; the main fuse trips or the transformer is overloaded. For example, five 22 kW wallboxes draw 110 kW at once, which most buildings cannot handle. Load management prevents this overload by sharing power among the vehicles, and allows more charging points to be installed on the existing infrastructure without an expensive connection-power upgrade or transformer investment.
What does phase balancing do?
In most corporate facilities in Türkiye, electricity is supplied over three phases (three-phase); some vehicles and devices draw power from a single phase, others from three phases. If charging loads are distributed unevenly across the phases, one phase becomes overloaded while the others sit idle; this leads to fuses tripping and inefficient use of capacity. Phase balancing distributes the charging load as evenly as possible across the three phases, ensuring that no single phase is overloaded. Smart load management systems monitor which vehicle draws from which phase to optimise the distribution and help get maximum benefit from the available capacity.
What role does OCPP play in load management?
OCPP (Open Charge Point Protocol) is an open communication standard spoken between the chargers and the central management software (CSMS). In multi-device installations, load management needs a central brain; the CSMS sees the status of all stations, sets current limits, and sends commands to share power among the devices. OCPP-compatible devices can be monitored remotely, grouped, and managed with smart charging profiles. An administrator can centrally set up scenarios such as prioritising charging during the night tariff, reducing power at certain hours, or defining different limits for vehicle groups. Bemis's OCPP-compatible models are suited to this kind of smart management.
Is load management needed for a single wallbox as well?
In a standalone installation with a single wallbox that does not share its connection with any other charging point (for example a detached villa), load management is not mandatory; the device operates on its own within the available capacity. However, if two or more charging points share the same connection, the situation changes: if the vehicles all want to charge at full power at once, total demand may exceed the limit. That is why load management is in practice a necessity in all multi-point installations such as apartment buildings, workplaces, shopping malls and fleets. When planning the installation from the outset, the power budget and the likely number of simultaneous vehicles must be taken into account.
Does load management slow down charging speed?
Load management does not charge vehicles slowly all the time; it only temporarily reduces charging power when total demand approaches the site's safe limit. When capacity is free, for example at night with only a few vehicles connected, each vehicle charges at its full power. When a vehicle finishes charging and leaves, the freed-up power is automatically transferred to the vehicles still charging. So total charging time may lengthen slightly only during the brief moments when many vehicles peak at the same time; because vehicles are usually parked all night, this delay is not noticeable in practice and all vehicles are ready by morning.
