Research
HyreSolar research
Twelve studies of American residential solar, each built from primary public data and published with its method and sources.
What this is
We publish original analysis of US residential solar computed from primary sources, chiefly Form EIA-861 (the mandatory annual census of American electric utilities, covering 2014 to 2024), plus California’s utility interconnection records and court filings. Every study states its method, names its source files, and publishes what it cannot establish alongside what it can.
Figures we calculate are labeled as calculations and are never presented as reported statistics. Twelve studies are live, three more are in collection; each carries its full data tables, charts, methodology, limitations and citation terms.
The national picture, in one chart
Household rooftop solar penetration varies enormously between US states. Hawaii is at 22.0%; Tennessee is at 0.0027%. The national figure of 3.55% describes almost nowhere.
The studies
What changed this year
2024 is the first year in the eleven-year series in which new residential solar connections fell sharply, from 761,174 to 527,942, -30.6%. Roughly half of that is California working through the aftermath of its April 2023 tariff change.
The caveat we put on the analysis rather than in a footnote: this is the sharpest fall in the series, not the lowest level. 2024’s 527,942 connections still exceed every year before 2022, and the installed fleet grew to 5,077,543 systems.
The program in numbers
The rules we hold ourselves to
Statistics are traced to the organization that produced them. We do not repeat a figure because other sites repeat it, and we do not cite a secondary source when the primary file is downloadable.
Where we compute a ratio, a rank or a rate from source data, it says so. Nothing we derive is presented as a reported statistic, and nothing third-party is presented as our research.
Every figure and every mark on every chart is generated from one dataset by script. A number in a sentence and the same number in the table below it cannot disagree.
Each study states its source files, inclusion criteria, exclusions, formula and validation, in enough detail for someone to reproduce or refute it.
Every study carries a limitations section. Where a result depends on an outlier or a reporting quirk, we say so in the finding itself, and one whole study exists to measure the main limitation of the others.
Where a state files nothing we show nothing, rather than assuming zero. Where a series moves oddly because of reporting rather than reality (Vermont in 2024, Hawaii in 2018) we flag it rather than adjusting it away.
The correlation table includes the coefficients that run against the industry’s usual story. The slowdown study states the baseline that makes its own headline smaller.
We do not publish per-company compliance findings from a database snapshot, we do not assert causation from a cross-sectional correlation, and we withheld an entire metric (battery capacity per system) because it failed a physical plausibility check.
Using this research
Journalists, researchers and analysts are welcome to cite and reproduce these findings, including the charts. We ask for a link to the study page, because the methodology and limitations live there and a figure quoted without them is easy to misread, several of the numbers in this section carry conditions that change what they mean.
Every study names its source files precisely enough to be checked independently, and each carries its own citation format, reuse terms and corrections policy at the foot of the page.
If you find an error, we would rather hear it than not. Corrections are made on the page with a dated note, not silently.
Questions
Where does the data in these studies come from?
Which figures are yours and which are reported by someone else?
Can I cite or reproduce these findings and charts?
What happens when you get something wrong?
Written and audited by
HyreSolar Research
Primary-source research, data analysis and fact checking
We are a research desk, not a sales floor. We read the statute, the tariff, the code section, the federal filing or the manufacturer data sheet ourselves, and we publish the figure with the document it came from and the date we retrieved it.
Where a number cannot be traced to a primary source, we publish the shorter page and say what we could not verify. That rule has cost us whole sections, and it is why the rest can be checked.
- 160
- primary sources read and cited
- 228
- figures with a retrieval date
- 115
- federal and state government sources
- 66
- researched pages published
How this desk works
- Primary sources only. Statutes from the legislature’s own publishing system, federal data from the agency that collects it, code text from the adopted edition, manufacturer claims from the data sheet. We do not cite an article that cites a source; we go and read the source.
- Every figure carries its provenance. A named document and the date we retrieved it, so you can check it and so you know how old it is. Retrieval dates are not decoration: an EIA rate from May is a different fact from an EIA rate from August.
- We publish what we could not verify. Every research page carries a section naming the things we tried to establish and could not, and why. A paywalled standard, a state website that refused the request, a manufacturer that publishes no figure at all.
- We separate measurement from modeling from our own reasoning, and label which is which on the page. A laboratory measurement, an assumption inside a modeling tool and our own inference are three different kinds of claim and they are never presented as one.
- We do not sell solar, and we take no payment for placement, ranking or a favorable mention. Nobody buys a position on this site.
Data as of EIA-861 2024 final release. Authorship on this site is organizational: the analysis belongs to the desk rather than to a named individual, and we do not publish credentials we do not hold. Our editorial policy sets out how we source, date and correct what we publish.
Sources & retrieval dates
Working out whether solar pays on your roof
State averages describe a market. The model prices a specific house on a specific tariff.
HyreSolar is an independent analysis and matching service. We are not an installer, lender or utility. When a reader asks to be introduced, installers may pay us a referral fee. That fee never buys ranking, scores or placement in research. Our editorial policy sets out the rules.