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Interstate Power and Light Co rate plans
3 residential plans are currently open to new customers. Some charge different prices depending on the hour — which is where most of the savings hide.
How much does the plan you pick actually matter here?
Run the same three-bedroom house with central air through every plan Interstate Power and Light Co files, and the bill lands anywhere between $921 and $1,727 a year. That $806 spread is not a difference in electricity — it is the same kilowatt-hours, from the same wires, priced under different rules. Nobody sends you a letter when you are on the wrong side of it.
The plan most households land on by default, Electric Residential Service Usage - 400, comes to about $1,716. The cheapest option here, Electric Residential Service Optional Demand - 507, comes to $921 — a gap of about $795 a year for a household that never changed a single habit. Whether you can actually capture that depends on when you use power, which is what the calculator below is for.
1 of these 3 plans price by the hour. Those are the ones where moving laundry, dishes, or car charging into the cheap window changes the bill; on the rest, the clock is irrelevant and only the total matters. Which camp you belong in is the first question worth settling, because it decides whether shifting your day is worth anything at all.
Which plan would cost you least?
No bill upload, no sign-up. Tell us roughly what you use and what runs on electricity — we price every plan against the same household and show you the gap.
That adds up to 7,914 kWh a year. Compare it to the total on your bill and adjust until it’s close.
Same usage, different plan
$658a year
That is the gap between the cheapest plan you could be on — Electric Residential Service Optional Demand - 507 — and the priciest. Not by using less power. By being billed differently for the same power.
| Plan | Per year | Vs best |
|---|---|---|
| Electric Residential Service Optional Demand - 507Peak hits 7pm–2pm, 2pm–7pm in Jun–Aug — every day. | $787 | — |
| Electric Residential Service Usage Time of Day - 407Peak hits 7pm–2pm, 2pm–7pm in Jun–Aug — every day. | $1,442 | +$655 |
| Electric Residential Service Usage - 400The hour never matters here — only the season. Rates peak June–August. | $1,445 | +$658 |
An estimate, not a quote. Supply charges move month to month, and your real usage pattern is not exactly this one. What it does show reliably is the gap between plans — both are priced off the same assumptions.
Before you switch anything
- What is a time-of-use electricity rate?
The same kilowatt-hour, priced differently depending on when you use it.
- Should you switch to a time-of-use electricity plan?
A wide peak-to-off-peak gap is a lever, not a saving. Levers need something to move.
- How to compare electricity plans without getting it wrong
Six things that break a comparison, and the order to check them in.
Every plan, in detail
Hour-by-hour schedules, tier thresholds, and the tariff each one comes from.
- Electric Residential Service Optional Demand - 507demand charge
Peak hits 7pm–2pm, 2pm–7pm in Jun–Aug — every day.
7.2–12.5¢ - Electric Residential Service Usage - 400flat
The hour never matters here — only the season. Rates peak June–August.
15.1–18.5¢ - Electric Residential Service Usage Time of Day - 407time-of-use
Peak hits 7pm–2pm, 2pm–7pm in Jun–Aug — every day.
15.1–27.3¢