Calculate CO2 from Bytes - Adapted from https://www.websitecarbon.com/

carbon.ts

const KWG_PER_GB = 1.805
const RETURNING_VISITOR_PERCENTAGE = 0.75
const FIRST_TIME_VIEWING_PERCENTAGE = 0.25
const PERCENTAGE_OF_DATA_LOADED_ON_SUBSEQUENT_LOAD = 0.02
const CARBON_PER_KWG_GRID = 475
const CARBON_PER_KWG_RENEWABLE = 33.4
const PERCENTAGE_OF_ENERGY_IN_DATACENTER = 0.1008
const PERCENTAGE_OF_ENERGY_IN_TRANSMISSION_AND_END_USER = 0.8992
const CO2_GRAMS_TO_LITRES = 0.5562

export const getStatistics = (bytes: number) => {
  const adjustedBytes = adjustDataTransfer(bytes)
  const energy = energyConsumption(adjustedBytes)
  const co2Grid = getCo2Grid(energy)
  const co2Renewable = getCo2Renewable(energy)

  return {
    adjustedBytes,
    energy,
    co2: {
      grid: {
        grams: co2Grid,
        litres: co2ToLitres(co2Grid),
      },
      renewable: {
        grams: co2Renewable,
        litres: co2ToLitres(co2Renewable),
      },
    },
  }
}

const adjustDataTransfer = (val: number): number =>
  val * RETURNING_VISITOR_PERCENTAGE +
  PERCENTAGE_OF_DATA_LOADED_ON_SUBSEQUENT_LOAD * val * FIRST_TIME_VIEWING_PERCENTAGE

const energyConsumption = (bytes: number): number => bytes * (KWG_PER_GB / 1073741824)
const getCo2Grid = (energy: number): number => energy * CARBON_PER_KWG_GRID
const getCo2Renewable = (energy: number): number =>
  energy * PERCENTAGE_OF_ENERGY_IN_DATACENTER * CARBON_PER_KWG_RENEWABLE +
  (energy + PERCENTAGE_OF_ENERGY_IN_TRANSMISSION_AND_END_USER) * CARBON_PER_KWG_GRID
const co2ToLitres = (co2: number): number => co2 * CO2_GRAMS_TO_LITRES