Rooftop solar data for 788 North American cities

Every figure on this site comes from the same measured dataset: Google Solar API rooftop samples across 788 cities in North America. This page publishes the aggregates, including the CSV, so you can check our working.

Download the full dataset (CSV) → 788 rows, 17 columns. Updated whenever the site rebuilds.

What this measures, and what it doesn't

Each city's figure is the median of roughly 16 individual rooftops sampled in a ring across the city's suburban area — not one reading from the city centre. That distinction is the whole reason this dataset exists: a single downtown sample produced results so distorted that Charlotte appeared to get less sun than Vancouver. Sampling a spread of real suburban roofs and taking the median fixed it.

The sunlight figure is usable sunlight. It already has shading from trees, chimneys and neighbouring buildings subtracted, which is why these numbers are lower than the "hours of daylight" figures published elsewhere. The unshaded column is what an unobstructed roof in the same city reaches, and the gap between the two is the shading loss.

What it is not: it is not a measurement of your roof, and it is not a forecast. Payback figures are modelled from the measured sunlight plus regional average electricity rates, using 400W panels at $2.85/W. Local incentives, your actual usage and your utility's export rules will all move the answer.

The headline finding: sunlight is not what decides this

Palmdale tops the sunlight table at 2,115 hours and Inverness sits last at 759 — a 2.8× spread. But the fastest payback in the dataset belongs to Honolulu, HI at 3.1 years, on 1,787 sun hours — well short of the sunniest city.

Electricity price moves payback far more than sunlight does. A dim city with expensive power beats a sunny city with cheap power, consistently, across the whole table. That is the single most useful thing in this dataset and it is the opposite of how solar is usually marketed.

Fastest payback

Most sunlight

Least sunlight

Shading

State College, PA loses the most sunlight to obstruction of any city measured — 20.5% below what an unshaded roof there would receive. Shading loss is the column most likely to differ from whatever a national calculator assumed about your roof.

Using this data

These are aggregate statistics we derived — the median of roughly 16 rooftop samples per city, not raw measurements — published so you can check our working rather than take our word for it. Free to reference and cite:

PanelFit, Rooftop solar statistics for 788 cities, derived from Google Solar API sampling. https://solarpanelfit.com/solar-data

The underlying rooftop measurements come from Google's Solar API and remain subject to Google's terms, which restrict redistribution of the underlying data. We are not granting a licence to redistribute it — what we publish here is our own sampling and aggregation, offered for reference and verification.

Generated 2026-08-22. Estimates only — not a quote and not financial advice.