Managed Unidirectional Charging (V1G)

Last modified: Aug 02, 2026

V1G controls EV charging without reversing the direction of electrical energy flow.

What V1G means

Managed unidirectional charging, often called V1G, controls when or how quickly an EV charges while electrical energy continues to flow only from the grid or site into the vehicle. A schedule, electricity price, site-capacity limit, grid signal, or fleet requirement may influence the charging power.

V1G can move demand away from expensive or congested periods, keep a site below an electrical limit, or coordinate many vehicles while still meeting departure-energy targets. The result depends on reliable communication, the vehicle's charging limits, charger capabilities, available connection time, and the control strategy.

V1G versus bidirectional charging

The defining boundary is power direction. V1G may raise, reduce, pause, or resume charging, but it does not export energy from the vehicle. V2H, V2B, and V2G require compatible bidirectional hardware and controls that can move energy out of the battery.

“Managed charging” is sometimes used more broadly for any coordinated EV charging program. V1G is the unidirectional part of that broader field. Guidance from the US Department of Energy distinguishes managed charging from bidirectional use and describes controls based on site and fleet needs. US Department of Energy: Managed and bidirectional charging

See Smart charging and grid integration for control strategies and Bidirectional charging for reversible power flow.

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