Wood pellets or ekogroszek coal? The maths without cheerleading

We run a pellet-price service, so it's proper to start with a declaration: we'll do the sum honestly, even if the result doesn't come out on our side. And it doesn't — at prices from the end of August 2026, the energy contained in ekogroszek (Polish graded heating coal) costs distinctly less than in pellets. Anyone who claims otherwise isn't showing the arithmetic.

The arithmetic doesn't end the discussion, though, because the choice between these fuels is in practice a choice of boiler for years, not of fuel for a season. Step by step.

Why you don't compare prices per tonne

A tonne is not a tonne: these fuels carry different amounts of energy per kilogram. Certified pellets have a calorific value of at least 4.6 kWh/kg (≥ 16.5 MJ/kg) — a hard threshold of the standard. Standard ekogroszek, according to trade guides, is about 24–25 MJ/kg, premium grades 27–29 MJ/kg. A kilogram of ekogroszek therefore carries about half as much energy again as a kilogram of pellets — so the only sensible comparison is złoty per kilowatt-hour of energy in the fuel.

Today's sum

Pellet prices are from our own measurements (as of 31 Aug 2026 — current ones here): the cheapest available A1 offer was 2,051 zł/t, the median 2,449 zł/t. Ekogroszek prices — from trade reports of August 2026: typically 1,300–1,600 zł/t in bulk, about 1,500–1,800 zł/t bagged.

Fuel	Price	Energy per tonne	Cost of energy
A1 pellets (cheapest)	2,051 zł/t	≥ 4,600 kWh	about 45 gr/kWh
A1 pellets (median)	2,449 zł/t	≥ 4,600 kWh	about 53 gr/kWh
Ekogroszek, bulk	1,300–1,600 zł/t	about 6,700–6,900 kWh	about 19–24 gr/kWh
Ekogroszek, bagged	1,500–1,800 zł/t	about 6,700–6,900 kWh	about 22–27 gr/kWh

The conclusion without hedging: at today's prices, energy from ekogroszek costs roughly half what energy from pellets does. For a house burning the equivalent of 4 tonnes of pellets a year, that's a difference counted in thousands of złoty per season.

Two honest caveats on this table. First, we count the energy in the fuel, not the heat delivered to the house — how much of it reaches the radiators depends on the efficiency of the specific boiler. Second, both sides of the sum move: we measure pellet prices daily and they have been quite different before, and coal prices have their own history of jumps. Redo this sum on the day you decide — not a year earlier.

If ekogroszek is cheaper, why does anyone choose pellets?

Because the price of energy in the fuel is only one column of the sum, and the others aren't on the label.

Subsidies work one way. In the "Czyste Powietrze" (Clean Air) programme, the purchase and installation of coal boilers — including ekogroszek — has been a non-eligible cost since 1 January 2022. A pellet boiler can be funded, provided its design doesn't allow an emergency grate to be fitted (since 29 April 2025 the manufacturer submits a written declaration to that effect). If you're replacing a boiler with a grant, the state has effectively made part of the decision for you.

Local law can be stricter than national. Anti-smog resolutions in some provinces and municipalities restrict solid fuels or coal outright. Before investing in any solid-fuel boiler, check the resolution in force at your address — half an hour that can save an investment worth well over ten thousand złoty.

Ash and maintenance. Class A1 pellets leave at most 0.70% ash — a few kilograms from a tonne of fuel. Burning coal leaves noticeably more, which means emptying the ash pan and cleaning the boiler more often. Then there's smell and neighbours: wood smoke versus coal smoke is a difference you can sense in the yard.

Storage. Pellets are merciless with moisture — damp ones are fit for the bin, as we write separately. Coal is far less demanding in that respect. If all you have is a roof without walls, that's a real argument.

Renewability. Pellets are made from sawdust and wood residues; coal is a fossil fuel. For some buyers that's the deciding argument, for others irrelevant; we note it, we don't adjudicate.

The thing few people say outright

This choice isn't made every season. A pellet boiler bought with a grant can't even have the option of an emergency grate — so there is simply no legal back door to burning coal. Choosing a boiler, you choose a fuel for 10–15 years, together with its future, currently unknown prices. So the honest advice is: don't make this decision on the basis of one table from one month — including ours.

If you already have a pellet boiler, the sum above is purely theoretical for you, and the practical question is: how to buy pellets as cheaply as possible. That's what the price table, the season calculator and a price alert at a threshold you set yourself are for.

Sources

• topagrar.pl — "Ceny ekogroszku w sierpniu 2026. Ile trzeba zapłacić za tonę?" — prices from the PGG price list and depots (incl. 5–25 mm grade at 1,300.39 zł/t at 23–24 MJ/kg, list dated 17 Aug 2026), market offers in bulk and bags (Polish).
• kochanydom.pl — "Ceny ekogroszku 2026" — typical price ranges (bulk 1,300–1,600 zł/t, bagged 1,500–1,800 zł/t) and calorific values: standard 24–25 MJ/kg, premium 27–29 MJ/kg (Polish).
• ENplus® ST 1001:2022 (Bioenergy Europe / DEPI) — pellet calorific value ≥ 4.6 kWh/kg (≥ 16.5 MJ/kg) and ash ≤ 0.70% for class A1.
• czystepowietrze.gov.pl — notice on pellet boilers without an emergency grate — funding conditions for pellet boilers, manufacturer's declaration from 29 Apr 2025 (Polish).
• farmer.pl — "Czy kotły na ekogroszek są objęte dotacją z programu Czyste Powietrze?" — coal boilers a non-eligible cost since 1 Jan 2022 (Polish).

Pellet prices in the table come from our own measurements and are dated; the method and its limits (including the absence of delivery costs on both sides of the comparison) are described on /metoda (Polish).