The pellets used in KARMEK stoves are small, cylinder shaped material made from mechanically compressed wood. The pellets, which are free from glue and paint, generate combustion in full respect for nature, without damaging the stove components. This material is a result of a recycling process that develops waste from industrial wood shavings, in particular sawdust and the remains of deforestation, therefore an economic choice. Pellets are easy to use, elastic and produce a high heat output.

Wood was the first ever combustible used by man after the invention of fire, supported over time by coal, gas and oil. Today, it is experiencing great success thanks to its high output and combustion that does not increase the carbon dioxide content in the atmosphere. The wood, which is biologically combustible, is constantly reproduced thanks to the combined action of solar energy, carbon dioxide, water and dissolved mineral salts. It therefore contributes to maintaining a balanced ecosystem. The economic advantages of wood compared to other combustibles are obvious: it is the most convenient combustible on the market. If burned in fireplaces or high technology stoves, it has a heat output comparable with that of fossil fuels, however its level of pollution is less. The different features of wood influence its combustion output. It is therefore important to use some types of wood rather than others. Humidity also influences supply regularity and system loading, as well as the quality of the combustion: in fact, the energy content decreases considerably based on the increase of humidity content.