Carbon Calculator

The Carbon Calculator tool aims to calculate the CO2 emissions of any website. The tool is the porting in python of the WholeGrain Agency Carbon Calculator tool, but it is faster and with more metrics.

How it works

The tool uses the same algorithm of the original tool but it is faster because it doesn't call external APIs. Soon more infos in a Medium post (italian)

Requirements

Installation

Install the Green Web Foundation Dataset

Go to the Green Web Foundation, get the most updated link and substitute it in the following command:

mkdir data && cd data
curl https://tgwf-green-domains-live.s3.nl-ams.scw.cloud/green_urls_2021-12-08.db.gz | gunzip -c > green_urls.db

Install the Lighthouse tool

npm install -g lighthouse

Install the Carbon Calculator tool

pip install carbon-calculator

Using the tool

As Python Library

from carbon.calculator import CarbonCalculator
from carbon.services import LighthouseService, GreenWebService

# If lighthouse tool is installed globally the following row can be omitted
lighthouse = LighthouseService(lighthouse = PATH_OF_LIGHTHOUSE_TOOL)

# It loads the Green Web Dataset DB (must be a SQL3Lite file)
greenweb = GreenWebService(greenweb = PATH_URL_OF_GREEN_DB)

# It calculates CO2 emissions
carbon = CarbonCalculator(lighthouse=lighthouse, greenweb=greenweb)
carbon.footprint("https://www.unime.it")

print(carbon.co2_grams)

//0.29566587414592505

As Python Library from INI File

Example of config.ini file:

[GREENWEB]
GREENWEB_PATH = /Users/giovanni/projects/carbon-calculator/data/green_urls.db

[LIGHTHOUSE]
LIGHTHOUSE_PATH = /Users/giovanni/.nvm/versions/node/v14.17.6/bin/lighthouse

If Lighthouse tool is installed globally set the LIGHTHOUSE_PATH empty

from carbon.calculator import CarbonCalculator

carbon = CarbonCalculator.from_ini_file('config.ini')
carbon.footprint("https://www.unime.it")

print(carbon.co2_grams)

//0.29566587414592505

As Command Line Interface (CLI)

carbon-cli -h

usage: carbon-cli [-h] -db GREENWEB [-lh LIGHTHOUSE] website

Carbon Calculator - the tool calculates the carbon emissions (CO2) and green infos of any website

positional arguments:
  website               The URL to analyze

optional arguments:
  -h, --help            show this help message and exit
  -db GREENWEB, --greenweb GREENWEB
                        (Mandatory) - The path of the Green Web Foundation DB (SQL3Lite DB file)
  -lh LIGHTHOUSE, --lighthouse LIGHTHOUSE
                        (Optional) - The path of the Lighthouse tool

carbon-cli --greenweb=/Users/giovanni/projects/carbon-calculator/data/green_urls_2021-12-01.db  --lighthouse=/Users/giovanni/.nvm/versions/node/v14.17.6/bin/lighthouse https://www.unime.it

Output

{
    "date": "2021-12-10T16:07:20.881173+01:00",
    "url": "https://www.unime.it",
    "hosting_green": false,
    "co2_grams": 2.3048954692203547,
    "energy_kWh": 0.004852411514148116,
    "water_litres": 1.2819828599803613,
    "resources": {
        "transfer_size_bytes": {
            "total": 3823256,
            "total_weighted": 2886558,
            "html": 18332,
            "css": 220144,
            "javascript": 573821,
            "image": 2962769,
            "font": 1613,
            "audio": 0,
            "video": 0,
            "other": 46577
        },
        "resources_size_bytes": {
            "total": 8375362,
            "html": 278333,
            "css": 3448588,
            "javascript": 1645906,
            "image": 2955453,
            "font": 1268,
            "audio": 0,
            "video": 0,
            "other": 45814
        }
    }
}

Fields available

Name	Format	Detail	Example
co2_grams	float	The CO2 Emissions in grams	2.3048954692203547
date	YYYY-MM-DDThh:mm:ss.sTZD (ISO8601)	Date and time of the measurement	2021-12-10T16:07:20.881173+01:00
energy_kWh	float	The power energy consumed in kWh (kiloWatt-hour)	0.004852411514148116
hosting_green	boolean	boolean - true if the hosting is present in the Green Web Foundation DB otherwise false	True
resources	array	Info Resources (See table below)
url	string	The website to analyze	https://www.unime.it
water_litres	float	The amount of water to boil to emit the same amount of CO2 in the air	1.2819828599803613

Info Resources

Array key names	Format	Detail	Example
transfer_size_bytes[total]	int	The data traffic total in bytes (compressed)	3823256
transfer_size_bytes[total_weighted]	int	The weighted data traffic total in bytes (considering caches)	2886558
transfer_size_bytes[html]	int	The HTML data traffic total in bytes	18332
transfer_size_bytes[css]	int	The CSS data traffic total in bytes	220144
transfer_size_bytes[javascript]	int	The JAVASCRIPT data traffic total in bytes	573821
transfer_size_bytes[image]	int	The IMAGE data traffic total in bytes	2962769
transfer_size_bytes[font]	int	The FONT data traffic total in bytes	1613
transfer_size_bytes[audio]	int	The AUDIO data traffic total in bytes	0
transfer_size_bytes[video]	int	The VIDEO data traffic total in bytes	0
transfer_size_bytes[other]	int	The OTHER data traffic total in bytes	46577
resources_size_bytes[total]	int	The Web resources total size in bytes	8375362
resources_size_bytes[html]	int	The HTML resource size in bytes	278333
resources_size_bytes[css]	int	The CSS resources size in bytes	3448588
resources_size_bytes[javascript]	int	The JAVASCRIPT resources size in bytes	1645906
resources_size_bytes[image]	int	The IMAGE resources size in bytes	2955453
resources_size_bytes[font]	int	The FONT resources size in bytes	1268
resources_size_bytes[audio]	int	The AUDIO resources size in bytes	0
resources_size_bytes[video]	int	The VIDEO resources size in bytes	0
resources_size_bytes[other]	int	The OTHER resources size in bytes	45814

Resources

Lighthouse: github repo
Green Web Dataset: website

License

Carbon Calculator: MIT license
Green Web Dataset: Open Database License

Credits

Giovanni Pirrotta

gpirrotta / carbon-calculator