How we work out the cost per kWh
We compare offers on the energy in the pack, not only on the price of the bag. Packs under 100 kg are one table. Packs of 100 kg and over are the bulk pallet table. Each table is sorted by £/kWh on its own. Buying a tonne is a different decision from buying a 10 kg bag, so the two tables are not ranked against each other.
Gross calorific value
Gross calorific values, on a dry basis, come from the manufacturer’s published figures where we have them. For Homefire fuels we use the Homefire support page: Brazier 31,500 kJ/kg, and Ovals, Ecoal and Homefire 32,000 kJ/kg. One kilowatt-hour is 3,600 kJ, so Brazier is 8.750 kWh/kg and the 32,000 kJ/kg fuels are 8.889 kWh/kg. Supertherm, Oxbow Excell and Oxbow Red use the published gross values linked on the calorific values page. Anthracite grades, when added, use typical published gross values and are labelled as such.
Pounds per kWh
The figure is pack price (£) ÷ kilograms in the pack ÷ kWh/kg.
Delivery is shown in its own column and is not included in the energy price. A price change is a new row. If a check finds the same price, the date on that row is updated. If a check fails, the date stays on the last confirmed figure.
What we do not do
We do not invent prices. Every number is taken from a supplier page we checked, dated and linked. If a page is unavailable or the layout changes, that offer stays at its last confirmed figure until it can be verified again. The £/kWh column is the energy in the fuel. It is not the heat that reaches the room, and it is not a gas bill with the standing charge folded in.
The live board is the current snapshot.