Data Sources
Reviewed by Edward, publisher and site editor ·
The site separates calculation logic from input data. Formulas are documented on the methodology page, while electricity prices and vehicle specifications are tied to identifiable sources so readers can check the reporting period, market and assumed vehicle variant.
A source is used as a reference input, not as a claim that every household or every version of a vehicle has the same value. Country averages should be replaced with a personal tariff, and vehicle specifications should be checked against the exact model year and trim where accuracy matters.
European residential electricity prices
For European country comparisons, Eurostat is the preferred source where a suitable household electricity series is available. Eurostat publishes prices by consumption band and reporting period, which allows the site to identify the period behind a reference instead of presenting an unexplained web average.
National taxes, levies and tariff structures differ, so even an official national average is not a personal quote. The country pages therefore present the figure as an editable benchmark and keep the original reporting period visible.
United Kingdom electricity data
United Kingdom reference material uses Ofgem or other appropriate official energy publications depending on the figure being shown. Regulated price-cap information, typical consumption assumptions and supplier tariffs are not interchangeable, so the page identifies what type of figure is being used.
Drivers on dedicated EV tariffs should use their actual off-peak unit price in the calculator rather than a national or capped benchmark because the difference can be substantial.
United States electricity data
United States residential electricity references use U.S. Energy Information Administration material where applicable. Electricity prices vary materially between states, utilities and rate plans, so a national value is primarily useful for broad comparison.
A driver estimating a real charging bill should use the applicable utility rate, including the correct time-of-use period where one exists. Demand charges and fixed service charges are treated separately unless they are explicitly part of the per-kWh figure.
Other national sources
Where Eurostat, Ofgem or the U.S. EIA is not appropriate, the site uses an identifiable national regulator, statistical authority, government publication or utility source. The source name and period are stored with the country record so the figure can be reviewed rather than copied without context.
If a current authoritative figure cannot be established, the page should not imply false precision. Readers can report an outdated source or suggest a better primary reference through the contact page.
Vehicle battery capacity
Model pages prefer usable battery capacity from manufacturer documentation where available. Some manufacturers publish only gross capacity or use different capacities across markets and model years, so the assumed variant is stated on the page.
Battery capacity affects full-charge energy and charging-time examples, but it does not by itself determine running cost per kilometre. Vehicle consumption and electricity price are the key variables for distance cost.
Vehicle charging power
AC limits and DC peak capability are taken from manufacturer specifications, WLTP or EPA-related material, or other clearly identified references where appropriate. Peak DC power is labelled as a maximum because it is not the average rate for an entire session.
Charging times are checked against manufacturer 10-to-80-percent figures when available. Real sessions can differ because of battery temperature, state of charge, charger capability, software and the charging curve.
Vehicle efficiency figures
Where the site presents a realistic consumption figure, the objective is to reflect mixed real driving rather than the most favourable laboratory number. The exact source and assumptions should be checked when comparing different model years, wheel sizes or climates.
Efficiency is especially sensitive to motorway speed and cold weather. A single value is therefore a comparison reference rather than a guarantee of what a particular driver will see.
Review and correction policy
Data is reviewed when source publications change, when manufacturers revise specifications or when a credible correction is submitted. A page's reporting period remains visible even after the site software itself is updated so readers can distinguish a content refresh from a new underlying dataset.
Corrections should include the affected URL, disputed value and a stronger source where possible. This makes the issue reproducible and allows the underlying data record to be corrected rather than patching one displayed number in isolation.
Common questions
Why not use electricity prices from comparison blogs?
Primary or official sources provide a clearer reporting period and methodology, reducing the risk of copying an unexplained or outdated average.
Are country prices exact for every household?
No. They are reference benchmarks. Personal tariffs, taxes, time-of-use periods and supplier contracts can differ significantly.
Why can an EV model have different battery figures online?
Gross and usable capacity differ, and manufacturers may sell different battery variants across markets and model years.