Gridlight — energy Sankey

<!-- Original layout, SVG/CSS artwork and JavaScript © 2026 XXC Templates. MIT License.
Illustrative sample content and data; no real accounts, purchases or bookings. -->
<main>
  <header class="intro">
    <div>
      <div class="kicker">DATA STORIES / SAMPLE DATA</div>
      <h1>Gridlight — energy Sankey</h1>
      <p>
        Trace 200 MWh through an energy mix. Ribbon widths encode real values, with conserved totals
        at every source and destination.
      </p>
    </div>
    <span class="badge">INTERACTIVE SVG</span>
  </header>
  <section class="panel">
    <div class="chart-summary">
      <strong>200 <small>MWh</small></strong
      ><span>Supply balanced with demand</span>
    </div>
    <svg
      id="chart"
      viewBox="0 0 700 275"
      role="img"
      aria-label="Sankey diagram of energy sources and uses"
    ></svg>
    <div class="toolbar">
      <button id="change">Compare renewable scenario</button
      ><span class="badge" id="scenario">BASELINE MIX</span>
    </div>
    <output id="status" class="status" aria-live="polite"></output>
    <details class="data-table">
      <summary>View data table</summary>
      <div class="table-scroll"><table id="data-table"></table></div>
    </details>
  </section>
  <footer>Illustrative data · no external services · keyboard-accessible controls</footer>
</main>

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(() => {
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  function table(headers, rows) {
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    const caption = document.createElement("caption");
    caption.textContent = "Illustrative sample data";
    t.append(caption);
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  function selectButtons(selector, callback) {
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  const colors = ["#82b6ff", "#72dbc2", "#c5a4ff", "#f7bf7c", "#fa92b8", "#acd884"];
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  function draw() {
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        ? [
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            [35, 25, 10],
            [10, 20, 10],
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            [20, 30, 10],
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      sources = ["Solar", "Wind", "Grid"],
      targets = ["Homes", "Industry", "Storage"];
    const rows = values.map((r) => r.reduce((a, b) => a + b, 0)),
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    table(["Source", "Destination", "MWh"], records);
    $("#scenario").textContent = alternate ? "80% RENEWABLES" : "70% RENEWABLES";
  }
  $("#change").addEventListener("click", () => {
    alternate = !alternate;
    draw();
    status(
      alternate
        ? "Renewables supply 160 of 200 MWh. Every flow remains balanced."
        : "Baseline restored: 140 of 200 MWh is renewable.",
    );
  });
  draw();
})();