Why this tool exists
Energy sources arrive in different units: electricity in kWh, gas in kWh or volume, and wood or pellets by weight or load. Comparing the price labels directly can lead to the wrong conclusion. HeatSourceCalc puts them on the same basis: cost per useful kWh delivered.
Your numbers, visible assumptions
You can enter your own tariffs, efficiencies and demand. Every initial price is an example. We do not fetch live prices, choose an installer for you or ask you to submit your details to see a result.
The methodology explains the arithmetic and its limits. The results estimate running costs; they do not replace a home assessment or an installation quote.
Help improve the calculator
Corrections and practical suggestions are welcome. If a result looks wrong, send the scenario link or the input values with an explanation of what you expected. We can then check the same calculation.