Wood Pellet and Biomass Fuel Calculator

Who this is for

How fast the pellets go, and what that costs. Count the bags in store each time you check, note any delivery since, and the calculator works out the kilograms burned, kilograms per day, cost per day and how many bags the rest of the season needs at that pace.

Homes with a pellet stove or biomass boiler that buy fuel by the bag or the tonne and want to know what a day of heating costs and when to order again.

What this helps you track

• Bags delivered and bags left in store at each check
• Kilograms used between checks and per day
• Cost per day at the price you paid
• Totals for the season so far
• Bags still to order for the days you expect to heat

How to use it

1. Write the fuel type, the bag weight printed on the bag, the price you pay per bag and the store capacity. If you buy by the tonne, work out the price per bag from your invoice.
2. Count the full bags in store and write the date and the count on the first row, and put that date in the header as the first check date.
3. At each check, write any bags added since the last one and the new count in store.
4. The kilograms used, days, kg per day and cost per day are worked out in the browser and the workbook; on paper, add the bags delivered to the last count, take off the new count and multiply by the bag weight.
5. Enter the number of heating days you expect are left in the season to see the bags still to order, set against the last count in store.

Formats

• Printable PDF (A4 and US Letter)
• Fillable PDF with form fields
• Fill in online, saved in your browser
• Excel / Google Sheets workbook

The printable is laid out inside a box that fits both A4 and US Letter, so the two files are identical and neither one is scaled. The fillable PDF has real form fields. The workbook uses plain formulas only — SUM, IF, COUNTIF and the like — so it opens in Excel, LibreOffice and Google Sheets without anything breaking, and every calculated cell is grey so you can see which figures it worked out.

How to print

Download the A4 or US Letter file to match the paper in your printer, open it in a PDF reader and print at 100% — not "fit to page", which shrinks the writing space. Both files leave a 14 mm margin, which clears the unprintable edge on home printers. To print the online version with your entries in it, use the Print this sheet button, which prints only the sheet and none of the page around it. More on printing.

Questions

How many bags will I need for a season?

The sheet does not guess. It measures your own use between checks and projects it over the heating days you say are left. Early in the season that figure moves a lot; it settles as the checks build up.

I buy loose pellets by the tonne. Does it still work?

Yes. Set the bag weight to the unit you count in, for example the kilograms a hopper or a marked bin holds, and the price to what that unit costs you.

Why count bags rather than record what goes in the hopper?

Counting the store at intervals is quicker and misses nothing. Recording each hopper fill also works; write it as a delivery out of the store and keep the count going.

Can I use it for logs or woodchip?

If you buy and count them in consistent units, yes. For logs measured by the load, the existing wood burner and fuel log may suit better.