Fictional worked example

Set a timer on an idle entertainment strip

A household measures 8 W from a group of media devices while unused. The devices sit idle for 20 hours each day and the proposed timer disconnects them for 16 of those hours.

Open Calculator

Inputs and calculation

Baseline and alternative
Tool inputValue
CurrencyUSD
Power unitW
Power8
Hours per day20
Days or equivalent sessions30
Duty cycle (%)100
Energy price (USD per input kWh)0.25
Alternative power (W)8
Alternative hours per day4
Alternative duty cycle (%)100

Baseline: 8 ÷ 1,000 × 20 × 30 × 100% = 4.8 kWh. Alternative: 8 ÷ 1,000 × 4 × 30 × 100% = 0.96 kWh. Multiply both by 0.25; the baseline minus the alternative is USD 0.96.

Modeled difference · USD 0.96

What the comparison shows

The strip still uses 0.96 kWh during four hours of standby daily. The baseline standby bill was only 1.20.

Assumptions and limits

Model only the standby window. Active watching and any power used by the timer itself are outside the comparison.

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