How We Calculate This
Clean Energy Local — Methodology
Every local power plant profile on this site is built from public data, and every number in every profile is calculated the same way. This page explains where the data comes from, how we turn raw figures into plain language, and what our numbers do and don’t mean.
Where the data comes from
Facility information — location, ownership, capacity, generating equipment, fuels, and how much electricity each plant produced — comes from the U.S. Energy Information Administration (EIA), the federal agency that collects standardized reports from every power plant in the country (Forms 860 and 923). The figures on this site reflect the 2024 reporting year, the most recent complete year available, and are refreshed as the EIA publishes new annual data.
County air quality and health figures come from the American Lung Association’s State of the Air report for New York and from the U.S. EPA’s Air Quality Index monitoring. School district information comes from the National Center for Education Statistics.
No figure on this site is estimated or guessed. If a fact isn’t in the source data, the profile doesn’t state it.
“Enough electricity for about X homes”
This is the translation you’ll see most often. We take a facility’s annual electricity production and divide it by 10,000 kilowatt-hours — a round national-average figure for what one American home uses in a year.
Two things to keep in mind. First, “homes powered” describes a quantity of electricity, not actual service: the grid pools power from many sources, so no plant serves a specific set of households. Second, it’s an average — homes vary widely in how much electricity they use. The figure is meant to make an abstract number concrete, not to be precise to the last house. That’s why we round it and say “about.”
Carbon figures
For facilities that generate electricity without burning fuel — solar, wind, hydroelectric, and nuclear — profiles state the carbon dioxide avoided compared with producing the same electricity from the national mix of power sources. We use a national-average factor of 0.85 pounds of CO₂ per kilowatt-hour, convert the result to metric tons, and round it.
This is a comparison, not a measurement: it answers “how much CO₂ would producing this electricity the average way have released?” We apply it only to non-combustion facilities. Plants that burn captured landfill gas or farm biogas are renewable, but because they do combust fuel, their profiles describe the methane-capture function instead of claiming avoided emissions.
The comparisons (“about the same as…”)
To make large carbon figures easier to picture, each profile includes one everyday comparison. All of them are derived from the same avoided-emissions figure, using fixed national-average conversion rates per gigawatt-hour of clean generation:
- about 82.5 passenger vehicles driven for a year
- about 45,000 gallons of gasoline not burned
- about 950 barrels of oil not used
- about 400,000 pounds of coal not burned
- the carbon absorbed by about 400 acres of forest in a year
- about 150 tons of waste kept out of a landfill
Profiles rotate among these comparisons for variety; each one is an equivalent way of expressing the same underlying figure.
Rankings
When a profile says a facility is “the largest of New York’s hydroelectric plants” or “ranks #3 of 100 natural gas plants,” that ranking is computed directly from the full statewide dataset by 2024 electricity produced, and the comparison group is always stated. We never describe a facility as biggest, oldest, or first unless the data shows it.
Air quality and health figures
The county figures in each profile describe the county as a whole — they are not measurements at the facility, and no profile connects county health statistics to a specific plant. The at-risk figure is a count of cases across five conditions the American Lung Association tracks (childhood asthma, adult asthma, COPD, lung cancer, and cardiovascular disease), not a count of people, since one person can be counted under more than one condition. Ozone and particle pollution grades are shown where the report provides them; where it doesn’t, the profile says so.
Rounding
Calculated figures — homes, carbon tons, comparisons — are rounded to two significant figures and presented with “about” or “approximately.” Figures reported directly by the facility, such as capacity and annual generation, are shown as reported.
What these numbers are not
They are honest estimates built on national averages, suited for understanding scale and context. They are not meter readings, not facility-specific emissions measurements, and not a statement about which homes receive a plant’s electricity. Where precision exists in the source data, we use it; where a figure is a translation, we say so.
Spotted an error?
Source data can contain mistakes, and facilities change over time. If something in a profile looks wrong, please let us know through the contact page and we’ll check it against the source record.
