Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Monthly savings from shifting
$58
Daily savings
$2.24
Annual savings
$699
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How to use this
- 1Enter shiftable usage per day (kWh).
- 2Enter peak rate ($/kWh).
- 3Enter off-peak rate ($/kWh).
- 4Enter days per month you shift.
- 5Read your monthly savings from shifting on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Under a time-of-use (TOU) rate plan, electricity can cost 2-4x more during peak hours (typically 4-9pm) than overnight off-peak hours. This calculator estimates savings from shifting a specific amount of your usage — running the dishwasher, laundry, EV charging, or a battery discharge/charge cycle — from peak to off-peak windows. It's the core economic argument utilities and solar-plus-battery installers make for scheduling loads or adding storage, and this tool quantifies it in real dollars per month instead of a vague 'save money' pitch.
Worked example
Using the values the calculator loads with:
Inputs
- Shiftable usage per day: 8 kWh
- Peak rate: 0.42 $/kWh
- Off-peak rate: 0.14 $/kWh
- Days per month you shift: 26
Results
- Monthly savings from shifting: $58
- Daily savings: $2.24
- Annual savings: $699
What each field means
Inputs
- Shiftable usage per day (kWh)
- The shiftable usage per day used in the calculation, measured in kWh. Starts at 8 kWh so you have a working example on load.
- Peak rate ($/kWh)
- The peak rate used in the calculation, measured in $/kWh. Starts at 0.42 $/kWh so you have a working example on load. Accepted range: 0.05–1 $/kWh.
- Off-peak rate ($/kWh)
- The off-peak rate used in the calculation, measured in $/kWh. Starts at 0.14 $/kWh so you have a working example on load. Accepted range: 0.02–0.6 $/kWh.
- Days per month you shift
- The days per month you shift used in the calculation. Starts at 26 so you have a working example on load. Accepted range: 1–31.
Results
- Monthly savings from shifting
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Daily savings
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Annual savings
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What loads are realistic to shift?
Dishwasher, laundry, EV charging, and pool pump runtime are the easiest — they're not time-sensitive and most have delay-start timers. Water heater loads can shift with a smart controller or heat pump water heater timer. Anything requiring real-time comfort (AC, cooking) is harder to shift without a battery.
How much do peak and off-peak rates actually differ?
It varies widely by utility — California's TOU plans (like PG&E's EV2-A) can see peak rates near 40-50 cents/kWh versus 25-30 cents off-peak, roughly a 1.5-2x spread. Some utilities with more aggressive TOU signals go 3-4x, particularly ones with significant solar penetration and a sharp evening 'duck curve' ramp.
Does a battery make shifting easier?
Yes — instead of manually timing appliance use, a battery charges during cheap off-peak hours (or from solar during the day) and discharges automatically during the expensive peak window, capturing the rate spread on your whole home's peak-hour usage rather than just a few shiftable appliances.
Is switching to a TOU plan always worth it?
Only if you can actually shift meaningful usage away from peak hours. If your usage pattern is flat (e.g., always home during peak with AC running), a TOU plan can cost more than a flat rate — model both your peak and off-peak usage honestly before switching, not just the savings on the shiftable portion.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Time-of-Use Rate Shifting Savings Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/time-of-use-shifting
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/time-of-use-shifting" target="_blank" rel="noopener">Time-of-Use Rate Shifting Savings Calculator — RevenueLab</a> (2026).</p>
Source: [Time-of-Use Rate Shifting Savings Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/time-of-use-shifting) (2026).