PricePower/calculator/main.py

import datetime
import calendar
from typing import List

from fastapi import FastAPI
from fastapi.responses import RedirectResponse

from calculator.miner import get_energy_prices, get_eur_czk_ratio
from calculator.schema import CheapestHours, DayPrice, Price

from .consts import VAT

def days_in_month(year: int, month: int) -> int:
    return calendar.monthrange(year, month)[1]

app = FastAPI(title="Spot market home calculator", version="0.1", description="Calculate your energy costs based on spot market prices")

@app.get("/", description="Redirect to /docs")
def docs():
    return RedirectResponse(url="/docs")

docs = """
Return spot prices for the whole day with all fees included.<br>
<br>
Options:<br>
date - date in format YYYY-MM-DD, default is today<br>
hour - hour of the day, default is current hour, works only when date is today<br>
monthly_fees - monthly fees, default is 509.24 (D57d, BezDodavatele)<br>
daily_fees - daily fees, default is 4.18 (BezDodavatele)<br>
kwh_fees_low - additional fees per kWh in low tariff, usually distribution + other fees, default is 1.62421 (D57d, BezDodavatele)<br>
kwh_fees_high - additional fees per kWh in high tariff, usually distribution + other fees, default is 1.83474 (D57d, BezDodavatele)<br>
sell_fees - selling energy fees, default is 0.45 (BezDodavatele)<br>
num_cheapest_hours - number of cheapest hours to return, default is 8, use this to plan your consumption<br>
low_tariff_hours - list of low tariff hours, default is 0,1,2,3,4,5,6,7,9,10,11,13,14,16,17,18,20,21,22,23 (D57d, ČEZ)<br>
<br>
Output:<br>
spot - current spot prices on our market<br>
total - total price for the day including all fees and VAT<br>
sell - current spot prices minus sell_fees<br>
<br>
The final price on the invoice is calculated as:<br>
    monthly_fees + kWh consumption in low tariff * kwh_fees_low + kWh consumption in high tariff * kwh_fees_high<br>
<br>
Except spot and sell prices all prices include VAT.<br>
<br>
<br>
Integration into Home Assistant can be done in configuration.yaml file:<br>
<br>
```
sensor:
- platform: rest
  resource: "https://pricepower2.rostiapp.cz/price/day"
  name: "energy_price"
  value_template: "{{ value_json.total.now|round(2) }}"
  unit_of_measurement: "CZK/kWh"
- platform: rest
  resource: "https://pricepower2.rostiapp.cz/price/day"
  name: "energy_market_price"
  value_template: "{{ value_json.spot.now|round(2) }}"
  unit_of_measurement: "CZK/kWh"
- platform: rest
  resource: "https://pricepower2.rostiapp.cz/price/day"
  name: "energy_market_price_sell"
  value_template: "{{ value_json.sell.now|round(2) }}"
  unit_of_measurement: "CZK/kWh"
- platform: rest
  resource: "https://pricepower2.rostiapp.cz/price/day"
  name: "energy_cheap_hour"
  value_template: "{{ value_json.cheapest_hours.is_cheapest }}"
```

"""

@app.get("/price/day", description=docs)
@app.get("/price/day/{date}", description=docs)
def read_item(
    date: datetime.date=datetime.date.today(), 
    hour:int=datetime.datetime.now().hour, 
    monthly_fees: float = 509.24,
    daily_fees: float=4.18, 
    kwh_fees_low: float=1.62421, 
    kwh_fees_high: float=1.83474, 
    sell_fees: float=0.45, 
    low_tariff_hours:str="0,1,2,3,4,5,6,7,9,10,11,13,14,16,17,18,20,21,22,23", 
    no_cache:bool = False, 
    num_cheapest_hours:int = 8,
    ) -> DayPrice:
    is_today = datetime.date.today() == date
    
    low_tariff_hours_parsed = [int(x.strip()) for x in low_tariff_hours.split(",")]
    monthly_fees = (monthly_fees + daily_fees * days_in_month(date.year, date.month))
    monthly_fees_hour = monthly_fees / days_in_month(date.year, date.month) / 24
    currency_ratio = get_eur_czk_ratio(date, no_cache=no_cache)

    spot_hours = {}
    spot_hours_for_sell = {}
    spot_hours_total = {}
    spot_data = get_energy_prices(date, no_cache=no_cache)
    for hour, value in spot_data.items():
        kwh_fees = kwh_fees_low if int(hour) in low_tariff_hours_parsed else kwh_fees_high

        spot_hours[hour] = value / currency_ratio
        spot_hours_total[hour] = (value / currency_ratio + kwh_fees) * VAT
        spot_hours_for_sell[hour] = value / currency_ratio - sell_fees
    
    spot = Price(hours=spot_hours, now=spot_hours[str(hour)] if is_today else None)
    
    spot_hours_total_sorted = {k: v for k, v in sorted(spot_hours_total.items(), key=lambda item: item[1])}
    spot_total = Price(hours=spot_hours_total_sorted, now=spot_hours_total[str(hour)] if is_today else None)
    spot_for_sell = Price(hours=spot_hours_for_sell, now=spot_hours_for_sell[str(hour)] if is_today else None)

    cheapest_hours = [int(k) for k, v in list(spot_hours_total_sorted.items())[0:num_cheapest_hours]]

    data = DayPrice(
        monthly_fees=monthly_fees * VAT,
        monthly_fees_hour=monthly_fees_hour * VAT,
        kwh_fees_low=kwh_fees_low * VAT,
        kwh_fees_high=kwh_fees_high * VAT,
        sell_fees=sell_fees,
        low_tariff_hours=low_tariff_hours_parsed,
        vat=VAT,
        spot=spot,
        total=spot_total,
        sell=spot_for_sell,
        cheapest_hours=CheapestHours(hours=cheapest_hours, is_cheapest=hour in cheapest_hours if is_today else None)
    )
    return data