Skip to main content
This guide walks you through integrating Flex Lite into your EV charging platform. By the end, you’ll be able to send user charging schedules and receive optimized schedules that enable grid flexibility while maintaining user control.

​
Prerequisites

  • An Axle API token (see Authentication)
  • Basic site information (MPAN, address, postcode)
  • Ability to detect plug-in events
  • User’s desired charging schedule
  • Confirmed eligibility and user consent

​
Step 1: Onboard your user and asset

First, you need to register the user’s site and EV charger with Axle. This enables Flex Lite participation. Note that the relevant dispatch consent we need is limited_pause. This tells us that we’re allowed to insert pauses into the user’s charging schedule.

Onboard site and asset

Add sites and assets to the Axle platform

​
Example

{
  "site": {
    "mpan": "1234567890123",
    "postcode": "SW1A 1AA",
    "street_address": "10 Downing Street",
    "gave_boundary_meter_consent_at": "2025-01-01T12:00:00Z",
    "email": "user@example.com"
  },
  "asset": {
    "external_id": "charger-001",
    "type": "charger",
    "asset_model": "axle_charger_v1",
    "installation_date": "2026-03-26",
    "properties": {
      "power_kw": 7.4
    }
  },
  "dispatch_consent": {
    "dispatch_methods": ["limited_pause"]
  }
}
Save both site.id and asset.id from the response — you’ll need the asset ID for sending schedules and the site ID for rewards and offboarding.You can also look up IDs later using the asset’s external_id.
onboard-site-and-asset will return a 409 Conflict if the site or asset already exists. If you need to handle re-registration or update existing entities, use the Advanced Onboarding flow, which supports upsert semantics.

​
Step 2: Send plug-in event with charging schedule

When a user plugs in their EV, send their desired charging schedule to the plug-in-schedule endpoint. Axle will return a modified schedule optimized for grid flexibility.

Send plug-in schedule

Send a charging schedule and receive an optimised version

​
Example

{
  "charging_schedule": [
    {
      "start_timestamp": "2025-06-27T22:00:00+00:00",
      "end_timestamp": "2025-06-28T06:00:00+00:00"
    }
  ]
}
Notice the response includes a 1-hour pause (01:00–02:00) — this is where the grid flexibility happens. The user earns rewards for this pause while still receiving the charging they need.

​
Common questions

User actions always take precedence. If a user modifies their schedule or boosts charging after receiving the modified schedule from Axle, apply their requested changes and send Axle a new schedule.
Not every plug-in event will result in a modified schedule. Axle only adjusts schedules when there’s a grid flexibility opportunity that provides value. If no modification is beneficial, you’ll receive the original schedule back unchanged.
Axle’s optimization ensures the user receives sufficient energy based on their needs. The typical modification is a 30 minute pause, which maintains adequate charging for most use cases. If the original schedule is already tight, we may not modify it.

​
Step 3: Offboard (when needed)

When a user withdraws consent or disconnects their charger, offboard the site and assets to ensure:
  • Flex Lite participation is stopped
  • User data is handled according to retention policies

Offboard site and assets

Remove a site and its assets from the Axle platform

​
Next Steps

At this point, your users are onboarded and their schedules are being optimised. Now it’s time to set up revenue and payments.

Earning from EV Charging

Learn how to submit readings and manage user payments

Advanced Onboarding

Need more control? Use initialise and enrol for a step-by-step onboarding flow.

Migrate to Smart Charging

Ready for more revenue? See what changes when upgrading to Smart Charging.