HIGH-QUALITY PELLETS AND SOLID FUELS FOR SMART HEATING

Wood is a renewable energy source. When pellets are burned, they release exactly the amount of CO2 that the tree absorbed during its lifetime. Unlike fossil fuels such as coal, oil and gas, whose carbon is stored and sealed away, wood has a living carbon cycle. This is why heating with wood is considered CO2-neutral, because whether wood rots in the forest or is used for energy does not change the CO2 balance. Among wood fuels, pellets are the most efficient and highest quality fuel. They have a high calorific value, can be used fully automatically and burn with very low emissions.

Our wood pellets are made from compressed natural wood fibres, mainly in the form of sawdust, wood shavings and wood chips. These are produced in sawmills and the wood industry. Residual and waste wood such as crown wood and small-diameter wood, as well as storm-damaged, defective or crooked wood that is no longer suitable for processing in sawmills, can also be processed. Softwoods and conifers such as pine, spruce, fir, larch and Douglas fir are used. All raw materials come from 100 percent sustainable forestry and are sourced regionally in the vicinity of our plants. During pelletisation, the wood fibres are compressed under high pressure without the addition of chemical binders, with the lignin contained in the wood acting as a natural binder.

Calorific value and heating value are often used interchangeably in everyday language. From a physical point of view, however, they are calculated differently and therefore always differ from each other. The lower heating value (Hu) is the decisive factor for the energy content of wood pellets and pellet heating. The heating value of pellets is around 5 kWh/kg. The energy content of 1 kilogram of wood pellets is roughly equivalent to that of 0.5 litres of heating oil. The calorific value of pellets is crucial for calculating fuel requirements and, together with the bulk density of the pellets, is important for calculating the optimal size of the pellet storage facility.

The bulk density of pellets is approximately 600 to 750 kg/m³, and the raw density is over 1.12 tonnes per cubic metre. Three cubic metres of pellets correspond to approximately two tonnes of pellets. The bulk density of wood pellets must be at least 600 kg/m³ in order to meet the requirements of the ISO 17225-2 standard. The bulk density describes the weight of the loosely poured pellets per unit of volume, including the cavities between the pellets. Compared to wood chips, the bulk density of wood pellets is significantly higher. Wood chips have a bulk density of around 200 to 450 kg/m³, depending on the type of wood, moisture content and size of the chips. When stored, wood chips require significantly more volume than pellets for the same amount of energy. Pellets can also be transported more efficiently due to their higher bulk density and energy content. 

REKORD is our brand for high-quality premium pellets. The ENplus seal of approval guarantees that the pellets meet strict quality standards. Unlike a simple manufacturer's declaration, the strict ENplus certification system ensures that the values of the ISO 17225-2 standard are actually met or exceeded. High-quality pellets leave little ash, usually less than 0.6%. This minimises cleaning effort and extends the service life of the heating system. With an energy content of around 5 kWh/kg, our pellets have a high calorific value. Another quality feature is the smooth surface without cracks and an optimal distribution of longer and shorter pellets (5 to 44 mm). This ensures good conveyability in the heating system and even combustion. Low dust and abrasion levels allow for efficient use and low maintenance. The brightness of pellets is not an indicator of their purity, but rather a reflection of the natural colouring of different types of wood. Pine wood, for example, is darker in colour than spruce wood.

In general, you should use the fuel quality recommended by the manufacturer of the combustion system or boiler for normal operation. For domestic pellet stoves and pellet boilers, this is quality A1. ENplus A1-certified pellets guarantee consistently high quality, high calorific value and low ash content. They protect the heating system from damage, improve energy efficiency and ensure clean, environmentally friendly combustion. They also offer transparency about the origin and prevent the use of harmful additives or foreign objects. Inferior pellets may contain impurities and/or have a high moisture content, which can damage the heating system. Poor-quality pellets produce more ash, slag or residues that can affect the combustion chamber, heat exchanger or chimney.

Both wood briquettes and pellets are pressed from wood residues such as wood chips, shavings and sawdust. The difference between the two types lies mainly in their shape, size, production and intended use. Pellets are small, cylindrical pellets with a diameter of around 6 millimetres and a length of up to 4 centimetres. They are ideal for automatic pellet heating systems and stoves with automatic combustion control, efficient combustion and high ease of use. Wood briquettes are significantly larger, with a length of between 15 and 30 cm. They are available in cylindrical, octagonal or rectangular shapes (e.g. Nesto, Pinikay or RUF) and are generally used in manually fed wood-burning stoves as an alternative to firewood. Pellets are produced on ring die presses, while wood briquettes are produced on hydraulic or mechanical briquette presses, depending on the type. While a uniform standard has been established for wood pellets with ISO 17225-2, the quality of wood briquettes can vary greatly depending on the manufacturer and source. The wood briquette standard ISO 17225-3 is not necessarily adhered to by all manufacturers.