Digital Carbon Rating Scale of SWD v4, re-calculated with CO2.js

carbon-ratings-swdm-v4-co2.js

import { co2 } from "@tgwf/co2";

const swdmV4 = new co2({ model: "swd", version: 4 });

// Figures as of 2025-01-23
// https://sustainablewebdesign.org/digital-carbon-ratings/
const ratings = {
  "A+": 272.51,
  A: 531.15,
  B: 975.85,
  C: 1410.39,
  D: 1875.01,
  E: 2419.56,
  F: 2419.57,
};

/**
 * Re-calculate the Digital Carbon Rating Scale thresholds for each percentile transfer size,
 * to compare with official figures.
 */
Object.entries(ratings).forEach(([rating, ratingValue]) => {
  const estimate = swdmV4.perVisitTrace(ratingValue * 1000, false, {
    gridIntensity: {
      device: 494,
      dataCenter: 494,
      networks: 494,
    },
    firstVisitPercentage: 1,
    returnVisitPercentage: 0,
    dataReloadRatio: 0,
  });

  console.log(`${rating}: ${estimate.co2}`);
});