Primary sources for label rules

We prefer the authority responsible for the label or energy topic: the FTC for US EnergyGuide information, European Commission product guidance and EPREL for EU context, and GOV.UK for Great Britain and Northern Ireland distinctions. Source links let you check the original basis.

Other guides can use utility, energy-advice or manufacturer material for a clearly identified topic. A manufacturer’s example is not evidence that all appliances behave the same way. Competing websites may inform feature research; their default energy figures are not copied into our calculators as verified data.

Keep dates and geography visible

A guide’s update date records its editorial update. A source’s reference-check date records when it was checked for the cited explanation. Neither means an ongoing live feed. Changes to label regimes or tariffs require a new review. Great Britain and Northern Ireland are distinguished where their context differs.

Separate documented figures from chosen assumptions

Default calculator inputs are illustrative. Some guides also use named model figures from linked manufacturer documents or an official product register. Those energy figures are documented declarations, rather than measurements by Watt & Home. Each worked example identifies which figures come from a source and which tariff, frequency, purchase price or credit is chosen for the calculation.

Reference models are used to explain the method, not as a current buying shortlist. A source-check date does not establish local stock, a live retail price or independent product testing. Check the exact model, market, capacity, programme and document version before comparing candidates. Efficiency classes are not interchangeable consumption values across appliances or label versions.

We do not describe illustrative tariffs or prices as typical, current or nationally averaged. A calculator link can load a worked example's stated inputs, including its currency. Visitors should replace those inputs with their own values.

Dated price observations and source examples

The documented appliance examples retain model, capacity, market, test basis and document version. Some comparisons also identify a manufacturer-listed price observed on a stated date. That is a dated listing observation, not a live quote, stock guarantee or verified checkout total. The guide states whether tax, delivery or promotions are included. Other prices remain explicitly illustrative.

A weighted programme declaration is not the measured energy of every full-capacity load. Our measurement guide provides a blank record for actual observations. No firsthand appliance test is claimed without real readings and their conditions.

Published research measurements

When a guide uses external field measurements, we name the observer organizations, link the original report and retain the reported unit and task boundary. The US household dryer case study uses published research averages. Its annual routine, electricity price and replacement outlay are separately stated scenario assumptions. Missing raw readings are not reconstructed. Published averages, manufacturer declarations and our calculated projections have different evidence bases.

How the content is prepared

The Watt & Home Team in the USA builds and runs this website as an independent project, without a company or a separate editorial team. We use AI-assisted research and drafting, check cited source material and verify worked calculations. We identify the source of declared and measured energy figures. We have not performed independent appliance laboratory tests.

Content is published by the Watt & Home Team under the Watt & Home name. Our About page explains the project and its calculation disclaimer. The website has no paid product placements or affiliate links.

Corrections

Use the contact form with the page address, the statement or inputs in question and a supporting source. We investigate reported issues and update the explanation and editorial date when a substantive correction is made.

Reference register

These are the current sources used by the guides and tools. Follow each link for the original information; a past check date does not guarantee that a page is unchanged today.

Sources and product documents