Price-optimised smart charging schedules your sessions at the cheapest available hours — without you having to do anything after the initial setup.

How it works

When a charge intent is set to Price Optimise, the system:

1. Fetches day-ahead energy prices for your site's country area
2. Models your site constraints — node limits, active meter readings, any scheduled limits
3. Runs the optimiser — finds the cheapest charging windows that will meet the session target
4. Sends OCPP commands — starts, stops, and adjusts the charge rate automatically

The optimiser plans ahead across the full optimisation horizon, not just the current time slot. If conditions change (e.g. a new session starts nearby), it re-optimises automatically.

Setting up price optimisation

1. Make sure your site has a country area configured (this determines which energy market is used)
2. Create or edit a charge intent and set the type to Price Optimise
3. Assign the intent at the level that makes sense — site default, RFID, vehicle, or EVSE

Once active, the system handles everything from that point forward.

Negative spot prices

When spot prices go negative — meaning you are paid to consume electricity — the optimiser handles this correctly. Negative prices are visualised on the monitoring charts so you can see when this occurs.

Constraints are always respected

Price optimisation never violates your infrastructure limits. Node current limits, power limits, and external meter readings are all treated as hard constraints. The optimiser finds the cheapest schedule within those limits, not around them.

Setting a departure time

A departure time tells the optimiser the latest point by which the session must be complete. The system works backwards from that deadline to plan the most cost-efficient schedule that guarantees the vehicle is ready.

Departure times can be set:

• On the charge intent — applies to every session using that intent
• Per session — overridden by the driver or operator for a specific session

Setting a State of Charge target

A SoC target defines the battery level the vehicle should reach. For example: charge to 80% by 06:00.

When an SoC target is set, the optimiser:

• Estimates the energy required to reach the target (from vehicle integration or manual input)
• Plans charging windows that will deliver that energy before the deadline
• Re-optimises if the estimate changes (e.g. new SoC data arrives mid-session)

SoC data sources

The system uses the best available SoC source, in this order:

1. Vehicle integration — live SoC from the vehicle
2. IEC 15118-2 — SoC communicated via DC charger protocol
3. Manually entered SoC — set by the operator
4. Entered energy demand — kWh required (when SoC is unknown)
5. Fallback default — a configured default per vehicle class

Setting a kWh target

If SoC data is not available, you can set a kWh target instead — the number of kilowatt-hours to deliver before the departure time.

Automatic re-optimisation

The optimiser continuously monitors session progress against the target. If a session is falling behind, it re-optimises and adjusts the schedule.