Disclaimer

Last updated 19 August 2026

Estimates, not quotes

Every figure on this site is an estimate. Real costs depend on your specific tariff, meter type, standing charges, local taxes, climate, driving style, building fabric, equipment condition and installation quality. Treat our results as a well-reasoned starting point, not a quotation.

Not professional advice

KilowattCost does not provide financial, investment, tax, legal or engineering advice. Decisions involving significant expenditure — solar arrays, heat pumps, vehicle purchases, electrical work — should be made with a qualified professional who has assessed your property or circumstances directly.

Where our default figures come from

Default assumptions use published averages from sources including the U.S. Energy Information Administration and the National Renewable Energy Laboratory, listed individually on our methodology page. Averages are, by definition, wrong for most individuals. Your own tariff will give a better answer, and every input can be overridden.

Advertising disclosure

This site displays advertising, including through Google AdSense. Advertisements are selected by third-party systems and their presence is not an endorsement.

Affiliate disclosure

Some outbound links are affiliate or partner links. If you request a quote or make a purchase through one, we may earn a commission at no additional cost to you.

This does not influence our results. Calculator formulas are fixed, published and covered by automated tests; they produce the same number regardless of which partners appear on a page. Where the honest answer is that a purchase does not pay for itself, we say so — and several pages on this site do exactly that.

External links

We are not responsible for the content or accuracy of third-party sites.

Reporting an error

Found something wrong? Email hello@kilowattcost.com with the page and the inputs you used. Confirmed errors are corrected promptly and the page update date revised.