Methodology

• Electric

  We cover many states. How we compute the estimate depends on the data source:

  Benchmark (e.g. state PUC typical bill) — When we have a standardized typical bill at 1,000 kWh (e.g. Florida PSC Comparative Rate Statistics for FPL, Duke, TECO, and other investor-owned utilities):

  estimatedElectric = (typicalBill1000kwh / 1000) × assumedKwh

  The implied $/kWh is total ÷ 1,000; we scale by assumed monthly kWh.

  Price to Compare (PTC) in choice markets — In states with retail choice (e.g. Pennsylvania, Ohio, Illinois), we often use the utility’s “Price to Compare” for generation (supply) only. Distribution and delivery charges are billed separately by the utility. When we only have PTC, we sometimes add a separate delivery estimate (customer charge + ¢/kWh) so the city total you see is supply + delivery; that’s what you see in places like Illinois (ComEd).

  Tariff or single rate — When there’s no benchmark or PTC (e.g. municipal/co-op, or we use a single effective rate):

  estimatedElectric = baseMonthly + (energyRatePerKwh × assumedKwh)

  Tiered rates are not yet modeled; we use a single effective rate where applicable. In some choice markets we also list alternative supply options (other retail offers) alongside the default so you can compare. When a rate has caveats (e.g. adjustment factors, taxes/fees not included), we may show a short note on that city’s electric card.

• Water

  estimatedWater = baseMonthly + (ratePer1000Gal × (assumedGallons / 1000))

  Base charge plus volumetric rate applied to assumed gallons. We express the rate per 1,000 gallons for clarity.

• Sewer

  Depends on method:

  • flat: fixed monthly charge (flatMonthly).
  • percentOfWater: a percentage of the estimated water bill. We compute water first, then sewer = water × percentOfWater / 100.
  • capacityCommodity: some utilities use an ERU-based capacity charge plus commodity charge per 1,000 gallons. Capacity is per ERU (minimum 1 ERU); ERU = usage ÷ eruGallons (e.g. 7,000) rounded to the nearest 0.1. We use the city’s assumed water usage.
  • tiered: not yet modeled as a formula; we store a pre-calculated estimatedMonthly for display.
  • unknown: we use the stored estimatedMonthly as a manual estimate.
• Trash

  estimatedTrash = monthlyFee

  Trash is modeled as a fixed monthly fee. Curbside and recycling are typically bundled where applicable; we use one combined fee in those cases. When there’s no separate resident fee (e.g. covered by taxes or city services), we show $0 and may note that trash is bundled with municipal services.

• Total

  estimatedTotal = estimatedElectric + estimatedWater + estimatedSewer + estimatedTrash

Each city record stores assumed usage used in the formulas. We use the same defaults for comparison consistency:

• assumedKwh: typically 1,000 kWh per month. Used for electric only.
• assumedGallons: typically 5,000 gallons per month. Used for water and for sewer when sewer is percentOfWater or capacityCommodity.

Your actual usage may differ; adjust mentally or use the formulas with your own numbers.

For each utility component we store: sourceName, sourceUrl, and lastVerified (date). Rates should be taken from official utility or provider pages. City pages show “Sources” with clickable links and the last-verified date. The data freshness date shown on each city (e.g. “last verified …”) is the earliest of the four components’ last-verified dates, so you can see how current the overall estimate is.

Each utility component has a confidence of confirmed, estimated, or unknown. We show this on city pages as a badge next to each component:

• Confirmed — from an official source (tariff, rate sheet, PUC/commission data).
• Estimated — derived from benchmarks, typical bills, or comparable data; or a placeholder when we don’t have a direct official rate.
• Unknown — we haven’t assigned a confidence level.