energy-cost 0.2.3

Energy cost calculation

Energy cost

Python package to model your energy bill based on your energy consumption.

To use this library, you first specify the Tariff applicable to you in a yaml file. See the examples/tariffs directory for inspiration, with notebooks/tariffs.ipynb for a detailed walkthrough.

A lot of tariffs are based on an Index, which is a price that changes over time based on the market price of energy. We have built in support for fetching these prices from ENTSOE or defining them in a data file, see notebooks/index.ipynb for more info.

Then, you can use the Contract class to calculate your costs based on your consumption data. See notebooks/contract.ipynb for an example.

We already have some built in tariffs for the Belgian market, which you can find in src/energy_cost/data/be/. These are the distributor tariffs for the main Belgian distributors, as well as the government fees and taxes. We plan to expand this to other European countries in the future, feel free to contribute if you want to see your country's tariffs in the library!

Note on units: all consumption based costs are in €/MWh, all energy values are in MWh. All monetary values are in €.

Note on timezones: every method that takes timestamps as input also takes a timezone as input. All timestamps will be aligned to this timezone, and all outputs will be in this timezone as well. This means that you can use the library with any timezone, regardless of the timezone of the input data or the tariff definitions. By default, the timezone is set to UTC.

Example usage

First define the tariff from your distributor in a yaml file, for example:

- start: 2024-01-01T00:00:00+01:00
  consumption:
    constant_cost: 100.0
  injection:
    constant_cost: -20.0

Then, you can use the Contract class to calculate your costs based on your consumption data:

from energy_cost import Contract, Meter, Tariff
from energy_cost.data.be import distributors, fees, tax_rate

contract = Contract(
    provider=Tariff.from_yaml("../examples/tariffs/fixed.yml"),
    distributor=distributors["fluvius_imewo"],
    fees=[fees["flanders_residential"], fees["be_residential"]],
    tax_rate=tax_rate,
    timezone=ZoneInfo("Europe/Brussels"),
)

consumption = Meter(
    data=pd.DataFrame(
        {
            "timestamp": pd.date_range("2024-01-01T00:00:00+01:00", "2024-03-01T00:00:00+01:00", freq="15min"),
            "value": 0.0002,
        }
    )
)

contract.calculate_cost([consumption])

For more detailed examples, see the notebooks in the notebooks directory.

Development

Prerequisites

• Python 3.12+
• uv (fast Python package manager)

1. Install dependencies

uv sync
uv tool install poethepoet

2. Notebooks

You can easilly test the project using our notebooks. They are located in the notebooks directory and can be run with:

poe notebooks

Some notebooks make use of external APIs and require API keys. You can set these in a .env file in the root of the project, using the .env.example file as a template.

If you add new features, please add a new notebook to demonstrate them.

3. Run tests

poe test

4. Code quality (pre-commit)

Pre-commit hooks are configured out of the box. Install them once:

pre-commit install

Every commit will automatically run:

Tool	Task	Command
Ruff	Linting + auto-fix	poe lint
Ruff	Formatting	poe format
ty	Type checking	poe check

You can also run them manually at any time.

License

MIT