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Cold Water Laundry Savings Calculator

Calculate the energy savings from washing laundry in cold water instead of hot or warm.

Result

Annual Energy Savings
421 kWh
Annual Cost Savings
$67

Roughly 75-90% of the energy used by a washing machine goes toward heating the water, not running the motor - modern cold-water detergents are formulated to clean effectively without hot water for most everyday loads.

About the Cold Water Laundry Savings

Water heating accounts for the large majority of a washing machine's electricity use, so switching the temperature setting can meaningfully cut costs without changing detergent brand, wash cycle, or laundry routine. This calculator estimates the annual energy and cost savings from moving your laundry from a hot or warm setting down to cold water, using your own load volume and electricity rate.

How It Works

You select your current water setting, hot or warm, enter how many loads you run per week, and provide your electricity rate. The calculator looks up a fixed per-load kWh figure for your current setting, subtracts a much lower cold-water figure, and multiplies that difference by your weekly load count and 52 weeks to project annual kWh and dollar savings. The comparison isolates the water-heating portion of the wash cycle rather than the machine's total energy use.

Savings kWh per year = (current kWh per load minus 0.15 kWh per load) x loads per week x 52. Savings dollars per year = savings kWh per year x dollars per kWh. Current kWh per load is 3.5 for hot and 1.5 for warm.

Examples

Switching from warm to cold

At 6 loads per week on warm (1.5 kWh per load) and $0.16 per kWh, savings are (1.5 minus 0.15) x 6 x 52, which equals 421.2 kWh, or about $67 a year.

Switching from hot to cold

At 4 loads per week on hot (3.5 kWh per load) and $0.18 per kWh, savings are (3.5 minus 0.15) x 4 x 52, which equals 696.8 kWh, or about $125 a year.

Advantages

  • It quantifies a genuinely low-effort change, adjusting a dial on the washing machine, in terms most households actually care about, dollars saved per year.
  • It distinguishes between hot and warm starting points, since the savings potential differs substantially between the two and lumping them together would misstate the benefit.
  • It requires no purchase or installation, so the payback is effectively immediate compared to calculators that model appliance upgrades with upfront costs.

Common Mistakes

  • Assuming every washing machine uses the same energy for a "warm" setting, when the actual figure depends on the machine's water heater, fill level, and thermostat behavior.
  • Including loads that genuinely need hot water, such as sanitizing bedding during an illness in the household, in the switched-load count used for the calculation.
  • Confusing this calculator's laundry-specific savings with total household energy use, since it only accounts for the water-heating portion tied to the washing machine.

Edge Cases to Watch For

  • If the selected setting value does not resolve to "hot" or "warm" for any reason, the calculator falls back to the warm-water figure of 1.5 kWh per load rather than returning an error.
  • The cold-water baseline of 0.15 kWh per load still accounts for some energy used by the motor and any residual water heating, so it is not treated as a true zero.
  • The savings scale only with the loads you actually switch, so if you plan to keep certain loads, like heavily soiled items, on hot or warm, you should reduce the loads-per-week input to reflect only the loads being converted to cold.

Common Use Cases

  • Households looking for a no-cost way to reduce their electric bill without buying new equipment.
  • Renters who cannot install new appliances but can freely change the wash temperature setting on existing machines.
  • People comparing the cost of switching to a cold-water detergent formula against the financial benefit it would unlock.
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

Does cold water actually clean clothes as well as hot?

For most everyday laundry, yes - modern detergents are enzyme-formulated to work effectively in cold water, and cold washing is also gentler on fabric colors and elastic fibers. Hot water is still recommended for specific cases like heavily soiled items, cloth diapers, or bedding when someone in the household is sick.

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Conclusion

Because the underlying change costs nothing beyond, at most, a different detergent choice, the savings this calculator estimates are close to pure financial upside for most households that make the switch. The numbers are most accurate when the loads-per-week figure reflects only the wash loads you are realistically willing to run cold rather than your full laundry volume.