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Charging

EV charging and V2X

Smart charging up to 22 kW and a realistic picture of bidirectional charging.

Short answer

Smart AC charging up to 22 kW — actual power depends on the vehicle, the site's available grid capacity, load management and any battery buffer. Most usage is long parking, where several dynamically managed points deliver more than one fast point.

Many managed points, not one big one

When cars stand for hours, no point needs full power simultaneously. Dynamic load management shares the site's available capacity between points, stays within the main fuse and balances phases. That fits many more charging places under the same connection.

  • The vehicle's onboard charger often limits more than the charge point
  • Single-phase vehicles create phase imbalance
  • For fleets, readiness by departure time matters more than instantaneous power
  • A battery buffer enables short DC charging bursts without upgrading the connection
  • A charger's nameplate rating is not the grid connection capacity — the site's real available capacity decides
  • In depots and fleets, readiness by departure time matters, not the instantaneous peak

V2L, V2H, V2B and V2G

Bidirectionality is not one thing but four scenarios of increasing complexity. The further towards the grid you go, the more safety, metering and regulatory requirements apply.

Levels of bidirectional use
LevelWhat it meansKey precondition
V2LVehicle powers a standalone device through a socketVehicle support; never wired into the building
V2HVehicle powers selected home loadsBidirectional charger, transfer switch, anti-islanding
V2BVehicle participates in the building's energy balanceMetering, control and a user agreement
V2GVehicle exports energy or a service to the gridGrid approval, settlement metering and market rules

Never backfeed a vehicle into a household socket. It is life-threatening to both the user and grid workers, and is not permitted.

Compatibility and islanding

Bidirectional charging requires the vehicle, the charger and the building solution to support the same method and protocol. Compatibility must be verified model by model. If the goal is to power a home during an outage, anti-islanding protection and disconnection are added — a separate design and approval.

OCPP and ISO 15118 direction

OCPP is the direction between charge point and management system, ISO 15118 and ISO 15118-20 between vehicle and charge point (including Plug & Charge and bidirectional developments). Neither may be presented as universal support — it must be verified per model and firmware. HUBCORE tracks both but claims no completed certified integration here. In the first stage we use partner platforms for starting charging and payments.

HUBCORE fit filter

  • Controllability Can the device be safely limited, started and stopped through a documented interface?
  • Measurability Do we get trustworthy measurements (power, energy, phases, state, faults) at sufficient resolution?
  • Integrability Is the interface publicly documented (e.g. Modbus, SunSpec, REST, MQTT, OCPP) and versioned?
  • Local operation Do critical control and safety keep working when the vendor cloud or internet is down?
  • Security Is access authenticated, are rights scoped, is traffic encrypted and firmware updatable?
  • Serviceability Is it clear who owns maintenance, spare parts, firmware and fault resolution?
  • Scalability Can the solution grow (more points, kWh, sites) without redesigning the architecture?

HUBCORE's position

HUBCORE focuses on long-dwell normal charging and dynamic load management. V2X is a development direction for us; its promises must be measured on site and cleared for safety before being presented to a customer.

Not yet verified

  • Which vehicle models common in Estonia genuinely support documented V2H?
  • How should battery warranty impact be accounted for in bidirectional use?