Power Visualizer

Power Visualizer is a desktop GUI tool for simulating daily electricity usage and cost across devices and tariff schedules.

Requirements

See REQUIREMENTS.md for supported platforms and dependencies.

Installation

1. Create and activate a virtual environment:

   python -m venv .venv
   source .venv/bin/activate

   On Windows (PowerShell):

   python -m venv .venv
   .\.venv\Scripts\Activate.ps1

2. Install dependencies:

   pip install PySide6 astral

Run the app

From the repository root:

python -m powervis

You can also run the launcher script:

python powervis.py

Import formats

The app supports importing device catalogs and tariff schedules from JSON files.

Device import

Use Devices → Import… to load a device catalog. The file must be a JSON object where each key is a category name and the value is a list of devices.

Each device supports the following fields:

• name (string, required): Device label.
• power_w (number, required): Power draw in watts.
• usage_duration (string, required): Default duration. Supported formats:
  • H:MM (for example 1:30)
  • decimal hours (for example 1.5)
• variable_time (boolean, optional): true for scheduled devices, false for fixed-duration events.

Example (see basic-devices.json):

{
  "Kitchen": [
    {
      "name": "Kettle",
      "power_w": 3000,
      "usage_duration": "0:03",
      "variable_time": false
    }
  ]
}

After importing, choose which categories to include. You can also clear the current device list before importing.

Tariff import

Use Tariff → Import… to load a tariff schedule. The file must include the schema version uk-tariffs-1.0.

Minimum structure:

• schema_version: must be uk-tariffs-1.0.
• suppliers: list of suppliers, each with:
  • supplier_name
  • tariffs: list of tariffs, each with:
    • tariff_name
    • rates: list of rates. Each rate includes:
      • rate_gbp_per_kwh (number)
      • priority (number, optional)
      • schedule with:
        • day_sets: list of day sets (mon, tue, wed, thu, fri, sat, sun)
        • time_ranges: list of start/end in HH:MM 24-hour format

Example (see UK-tariffs.json):

{
  "schema_version": "uk-tariffs-1.0",
  "suppliers": [
    {
      "supplier_name": "Example Energy",
      "tariffs": [
        {
          "tariff_name": "Example Flat",
          "rates": [
            {
              "rate_gbp_per_kwh": 0.28,
              "schedule": {
                "day_sets": [{"days": ["mon", "tue", "wed", "thu", "fri", "sat", "sun"]}],
                "time_ranges": [{"start": "00:00", "end": "00:00"}]
              }
            }
          ]
        }
      ]
    }
  ]
}

After importing, choose Tariff → Select Tariff… to activate a specific supplier/tariff entry.