How figures get onto this site, and how they come off

The rule

A number may appear on this site only if it is one of three things: arithmetic on a visitor's own input, a figure attributed to a named publisher with the date it was retrieved, or an assumption labelled as such with its reasoning and plausible range. There is no fourth category, and the build refuses to render a number that is not registered as one of the three.

Sourcing

• Primary sources only for energy prices, climate data and regulatory requirements — the agency that publishes the series, not an aggregator that republished it.
• The raw response is retained with the build, so a figure can be checked against what the publisher actually said on the day.
• Where a published figure has a known weakness for the pool case — a state average standing in for a marginal rate, an annual figure standing in for a summer one — that weakness is printed next to the figure, not buried in a disclaimer.

Assumptions

Where no publisher supplies a number for a residential pool, the assumption is written down with the reasoning that produced it and the range within which we believe it sits, and it is exposed as an editable control. An assumption that cannot be edited by the reader is a hidden claim, and hidden claims are not permitted here.

Independence

No manufacturer, installer or retailer pays for placement, review or mention. No product is recommended by name. Where a category has a genuine weakness — the running cost of gas, the shoulder-season collapse of a heat pump, the disappointment of solar in April — it is stated in the same terms as its strengths.

Who writes this

Andrew Flores is responsible for the site's research, calculations, source verification, and corrections. A registered figure must carry a named publisher and retrieval date, documented arithmetic, or a visibly stated assumption; the policy allows no unlabeled fourth category.

Editorial responsibility for every page sits with a named person rather than a masthead, and the corrections address on the contact page reaches him. Nathan Management, a California publisher of single-purpose calculators, is the publisher of record.

Staleness

Energy prices go out of date, and the natural gas series used here is an annual figure that will be superseded by a later year. Every sourced figure therefore carries the date it was fetched, printed on the methodology page rather than hidden in a build log, so a reader can judge for themselves whether a figure is old enough to distrust. A stale figure with a visible date is a manageable problem; an undated figure is not, because nobody can tell whether it is a week old or three years old.

Where a figure has a natural revision cycle — monthly for electricity, annual for gas — the retrieval date is the honest description of what the site knows, not the publication date of the underlying series.

What is not published here

Three categories are excluded on principle. Installed prices, because they are local and any national figure would be invented. Product recommendations, because there is no way to rank equipment without either testing it or taking somebody's word, and this site does neither. And projections — of energy prices, of equipment life, of savings over a decade — because a projection dressed as a calculation is the most persuasive kind of made-up number.

Where a reader plainly needs a number in one of those categories, the site asks them for it and does the arithmetic around it. That is why the payback page takes two quotes rather than publishing a price table, and why it offers a price-sensitivity table rather than an escalation rate.

Language

Figures are stated with the precision the underlying source supports and no more. Where the model's output is uncertain, the page says which input drives the uncertainty rather than attaching a vague caveat to everything. Claims about what equipment does are written in terms of the physics that produces the behaviour, so that a reader can check the reasoning rather than take it on trust.

Corrections

Errors are corrected in the registry, which propagates to every page that used the figure. Where a correction changes a headline number materially, the change is noted on the methodology page rather than made silently. A correction is never made by quietly deleting the sentence that was wrong.