Editorial and calculator standards
SolarCalculatorHQ publishes free estimating tools and explanatory guides for homeowners, designers and installers. Editorial responsibility sits with the SolarCalculatorHQ editorial team. We do not present the team as licensed electricians, engineers, tax advisers or code officials. Our work is independent educational material, not a substitute for an engineered design, electrical approval, tax advice or installer quote.
How calculators are built
Each calculator begins with an explicit model: user inputs, electrical or financial formulas, conversion factors, performance losses and result assumptions. We test ordinary and boundary inputs, check unit conversions, and compare representative outputs with worked examples from primary or established industry sources. Safety-critical conductor, protection, structural and interconnection decisions must still be confirmed by qualified local professionals.
Source hierarchy
We prefer sources in this order:
- Government agencies, tax authorities, energy regulators, standards bodies and official program administrators.
- National laboratories, public datasets and research with a stated collection method.
- Manufacturer technical documents and current market reports with transparent scope.
- Installer or marketplace evidence used to test whether a planning range remains realistic.
Incentive rules are dated because eligibility, deeming periods, credit rates and program capacity can change quickly. Users should follow the linked program administrator or tax authority before relying on an incentive. Prices are planning ranges and may change with roof condition, equipment, labour, permitting, grid requirements, financing and product availability.
Localisation and review
Localised pages are reviewed as market-specific documents, not treated as word-for-word translations. We check currency, units, irradiance assumptions, electricity tariffs, named incentive programs, electrical terminology and internal links. A translated support page that has not received substantive local review is kept out of search indexing until it is ready.
Dates, changes and corrections
Content pages display their latest published or reviewed date. Material changes include formula corrections, revised market prices, incentive or tax changes, standards updates and replaced sources. Minor spelling or formatting edits may not change the date. When current primary guidance contradicts an older statement, the primary guidance controls and the page is corrected.
To report a calculation error, broken link or outdated rule, email contact@solarcalculatorhq.com with the page URL, location, inputs used and the result or source you believe should apply.
Funding and advertising
The site may display Google AdSense advertising. Advertising does not determine calculator outputs, source selection or editorial conclusions. We do not sell favourable rankings in guides or adjust estimates for advertisers.