Transparency

Methodology & data sources

Electricity rates

PowerCostAtlas uses residential average retail electricity prices from the U.S. Energy Information Administration (EIA), Electricity Sales to Ultimate Customers data series. The current local snapshot is May 2026.

Calculation

Energy used is power in kilowatts × time in hours. Cost is energy used in kWh × electricity price per kWh. The calculator converts the EIA rate from cents to dollars automatically.

What is not included

State averages do not capture a household's exact utility plan. Fixed monthly fees, taxes, demand charges, tiers, seasonal tariffs and time-of-use prices are not included unless the user accounts for them separately.

Update policy

A scheduled GitHub Actions workflow checks the EIA API for newly published monthly residential rates. When the dataset changes, the repository updates the local rate file and the hosting platform rebuilds the static site.

Automated content

Rate comparisons, example costs, rankings and calculator outputs are generated programmatically from the published dataset and displayed assumptions. Automation is used so that the same calculation method is applied consistently when EIA values change.

Source attribution

Source: U.S. Energy Information Administration. PowerCostAtlas is an independent project and is not endorsed by or affiliated with the EIA.