Wash at 30°C Calculator
See what switching your washing machine from 40°C to 30°C really saves a year, and what dropping one wash a week on top of that could add.
Estimate only. Estimates based on the cycle count, machine energy use and electricity rate you enter, your machine's actual energy label and your supplier's tariff may vary. Source: Energy Saving Trust.
Enter your laundry habits
Add your weekly wash cycles, machine energy use and electricity rate to see your saving.
Why washing at 30°C saves so much
Most of a washing machine's energy use goes on heating the water, not on the motor or spin cycle, so turning the temperature dial down is the single biggest lever you have. Energy Saving Trust estimates washing at 30°C uses around 40% less energy than washing the same load at 40°C, with no meaningful difference in cleaning performance for normal, everyday laundry thanks to modern low-temperature detergents. Combine that with only ever running full loads, cutting out one wash a week by batching loads together, and the two savings stack, since the dropped cycle is also washed at the cooler, cheaper temperature.
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