smart-charging
Axle provides a managed smart charging solution. This means that we’ll create charge plans for your users based on their needs and optimised for flexibility revenue.

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How does smart charging work?

Rather than charging a vehicle immediately upon plugin, smart charging allocates charging to the time of lowest cost. To do this, we need to know:
  • How much energy is required (kWh)
  • When the vehicle needs to be ready by (time)
We’ll take these requirements, combine them with the user’s tariff, and optimize them with respect to the flexibility markets that the user is registered in to formulate a charging schedule.

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Building smart charging with Axle

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Prerequisites

You’ll need to register the user & asset and collect tariff information to enable smart charging.

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Collecting intent

The easiest way to collect charge intent is to embed our prebuilt smart-charging component in your app.

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Energy Requirements

We want to know how much energy is required, in kWh. There are several ways to arrive at this number.
User providesNotes
kWh to addUser describes requirement in kWh
Hours to addRequires approximation of charge power
Target SOC %Requires current SOC % (Axle provides via Enode)
% to addRequires car battery size (Axle provides via Enode)
NothingCan be approximated or fixed to e.g. 4 hours charging

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Ready-by time

Collect ready-by with a standard time picker. This is bundled with energy requirements in our smart-charging component. For more customisation, you can collect separate ready-by times for different:
  • days of the week
  • vehicles
And communicate these via API when the relevant vehicle plugs in.

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Integration

Axle will issue new schedules when:
  • The user plugs in
  • The user’s tariff changes
  • The user’s intent changes
In all cases, these schedules are issued async.

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Communicating intent

We need to know the user’s most recent intent whenever we issue a charge schedule.

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Receiving charging schedules

If you already have an existing API that you think will support smart charging, we can discuss integrating with that directly. However, our recommendation is to integrate with our OCPP API.
We’ve developed an OCPP-based API to support smart charging. This provides the most robust, flexible solution for smart charging. You can see an example of the the dispatch events we send here. Building on top of OCPP has several advantages:
  • Specification of charge energy in an industry-standard format
  • Stacking of schedules allows fallbacks in case devices go offline. For instance, our schedules can be overlaid upon a “default” schedule which always charges consumers during off-peak times
  • Fine-grained control over recurrence type and expiries