Water use
Evidence-led explainers on water use, with every figure sourced.
Data centres use water for cooling. The widely circulated per-query figures are scenario outputs, not measurements — and the largest water use is usually the one nobody counts.
Agriculture takes about 70% of global freshwater withdrawal. Households take under a tenth. Almost every popular water-saving conversation is about the smallest number.
Seventy percent of global withdrawal, most of it consumed rather than returned — and the efficiency measures that seem obvious frequently do not work as expected.
What actually moves the needle, ranked by effect — and an honest account of how much household saving matters in the wider picture.
The figure for a kilogram of beef or a cup of coffee is a global average that mixes rainfall with abstracted water. Useful, and routinely over-read.
Generating electricity takes water, and moving and treating water takes electricity. The two systems constrain each other in ways that only become visible in a heatwave.
Industrial water use spans processes with almost nothing in common — from steel cooling to semiconductor rinsing at a purity beyond anything drinkable.