When interacting with our ecosystem, you will quickly discover a few core building blocks.
This page aims to explain what those are and what the idea behind them is.

Site

A Site is a location. It is the highest level of logical grouping in this model.
Most likely, you will only have one site: Your home 🏠

Each Site consists of metadata such as its location and a varying amount of Things.
Programmatically, it is represented by its Site Configuration.

Things

A Thing is a logical grouping of states and metrics representing the real physical things.
Since this is the Internet of Things, it only made sense to have things be called Things.

Examples of Things include:

Batteries
Charging Points
Energy Meters
Heat Pumps

etc.

Each Thing will have a varying amount of Data Points.

Data Points

Each Data Point is a single state or metric.

It consists of a specific type called key, which could for example be VOLTAGE_P1.
In that case, the Data Point represents the Voltage on Phase 1 of the Thing the Data Point is part of.

Furthermore, each Data Point has a dataType, which in this example would be NUMBER.
And, of course a unitOfMeasure, which would be V for VOLTAGE_P1.

As a full example, here's the metadata for the aforementioned Data Point that you'd find in the Site Configuration under the Thing it belongs to:

{
  "ecd3541e-f381-51c2-9dd7-e94d84df573a": {
    "key": "VOLTAGE_P1",
    "dataType": "NUMBER",
    "unitOfMeasure": "V"
  } 
}

And here's the state data for it:

[
  {
    "dataPointId": "ecd3541e-f381-51c2-9dd7-e94d84df573a",
    "key": "VOLTAGE_P1",
    "value": 229.93539428710938,
    "ts": 1707464760068
  }
]

Energy Flow

An Energy Flow is a derived view on the states and metrics of a Site provided by the Data Points.

It answers questions such as:

Where is energy coming from? (PV, Grid, Battery, etc.)
Where is energy going to? (Grid, Battery, Heat Pump, Charging Point, etc.)
How much energy is moving around?
How much energy is stored?
How much of the energy consumed at the site is not coming from the grid? (Self-sufficiency)

etc.