Rate Plan Switch Breakeven
Rather than testing one assumed rate spread, this solves backward: given the small cost of actually shifting your usage timing and how much usage you could realistically shift, what electricity rate makes that effort clear a fast target payback.
At your inputs, the electricity rate that hits a 1-year payback is $0.037/kWh.
| Required electricity rate | $0.037/kWh |
|---|---|
| Payback at your actual entered rate | 0.2 years |
- This uses planning estimates you entered, not a contractor quote or guaranteed savings.
- It solves for the electricity rate that meets your target payback; it does not predict future rates.
What this also tells you: Your actual entered rate gives a payback of 0.2 years; the rate above is only the threshold for your stated target, not a forecast.
This is a planning estimate based on your entries. It does not size equipment, determine electrical or building-code compliance, verify incentive eligibility, or replace a contractor quote or professional energy audit.
Why this decision comes up
A rate plan switch's value depends entirely on the rate spread and how much usage you can actually shift, and this isolates that sensitivity directly.
How this is calculated
Given the cost of shifting your usage timing, your realistic annual kWh shiftable to off-peak, and a target payback period, this solves for the electricity rate that makes those numbers work out exactly.
A worked example
With the defaults ($150 effort cost, 4,000 kWh/year shiftable, 1-year target), the required rate is $0.038/kWh, a very low threshold reflecting how cheap and fast this specific change typically pays back.
Common mistakes
A common mistake is overestimating how much usage you can realistically shift to off-peak hours. Be honest about which appliances and habits can actually move.
Limitations
This does not verify your actual usage pattern or your utility's exact off-peak rate. Use your utility's usage data for a more accurate estimate.
Common questions
Why does this use such a short target payback by default?
The cost involved is typically small (a smart plug, a scheduling change), so a fast payback target is realistic. Adjust it if your actual switching effort involves a bigger investment.
What does the "cost" input represent here?
It represents any equipment or effort cost involved in actually shifting your usage timing, not the cost of switching plans itself, which is often free.
How is this different from the time-of-use vs. flat rate comparison?
That tool compares both plans' full total cost directly. This one solves backward for the rate threshold, useful for judging how sensitive the decision is to your specific rate.
What if I can't realistically shift any usage at all?
Then a plan switch built around usage shifting likely won't help you regardless of the rate spread. The time-of-use vs. flat rate tool, using your actual unshifted usage pattern, gives a more honest answer for that situation.
Does this assume a specific appliance, like an EV charger, is doing the shifting?
No, this is generic. Enter whatever combined shiftable usage you realistically expect across all your flexible loads, EV charging, laundry, or otherwise.