FAQs - Frequently Asked Questions about pellets and pellet heating

Questions about fuel- We have the answers!

1. What are pellets?
   

   Wood pellets are cylindrical pellets made of dry, natural wood waste (sawdust and shavings) with a diameter of 5-6 mm and a length of 10-25 mm. They are compressed under high pressure (without chemical binders) and have an extremely low water content. Wood pellets are supplied in kilograms. 1m³ of pellets weighs 650 kg.

   As a comparison:

   2 kg pellets ...................approx. 1 litre of oil

   1 m³ pellets ...............approx. 320 litres of oil

   for more information see here. 
    

2. What is the calorific value of pellets?  
   The calorific value is standardized at 4.9 kWh/kg. Quality is important! For optimal functioning of your pellet heating system use only pellets which comply with Ö-norm or DIN-plus standards. 
   
3. How does the calorific value of pellets compare with oil and gas?  
   The calorific value of one litre of extra light oil amounts to 10 kWh, as does the calorific value of 1m³ of gas. It is therefore true that: 2kg pellets ~ 1 litre extra light oil ~ 1m³ gas. In terms of price pellets do significantly better than oil and gas.
    
4. How long can pellets be stored? 
   In dry conditions pellets can be stored indefinitely. Attention: if pellets come into contact with water or damp they will expand and be destroyed. 
   
5. Where do I get the pellets and where are they stored? 
   Wood and therefore wood pellets are an indigenous resource and therefore a regionally available energy source, available from conventional solid fuel suppliers. A small network of producers and dealers can supply a large area. The pellets are delivered by tanker truck, from which they are blown into the pellet store or tank. Unlike oil, pellets do not smell unpleasant! Pellets can be stored in dry storage rooms or in FlexiTanks or otherwise in silo bags. The best storage system will depend on the building type, but an especially cost-efficient option is our FlexiTank. The FlexiTank can be installed in the boiler room, in an adjacent building, or outdoors (if placed outdoors, the FlexiTank must be protected against rain and UV-light).
    
6. How much energy is consumed in the production and transport of pellets? 
   The energy consumption for the production of pellets is approximately 2.7% of the calorific value of the pellets, compared to LPG at 14.5%, oil at 12%, and natural gas at 10% (Source: Jensch u. Bergmaier, TU Graz University 1997).  
    
7. How is the quality of pellets identified?
   There are industry standards which set quality criteria for wood pellets. They include not only the calorific value but also the density, water content, amount of ash, length and diameter, abrasion resistance and the defined capacity (i.e. the number of pellets in a given volume of space). When buying pellets please ensure that you obtain them from certified producers who mark the product as complying with Ö-norm or DIN-plus standards. 
   
8. Can fuel supply be guaranteed?
   In Austria, Germany and Switzerland the supply of pellets is guaranteed by an extensive network of distributors. In the UK and Ireland systems will only be installed in areas where fuel is available, and here fuel supply is assured by the regional distributor who will also assist customers in sourcing fuel of the correct quality. The fact that wood is an indigenous resource, and the domestic nature of pellet manufacturing means that pellets are independent of fluctuations in the oil market and foreign energy imports. Already the installed production capacity of wood pellet plants is sized to suit the growing future market, and a deficit in wood supply cannot be expected in the foreseeable future thanks to the millions of tons of residual wood waste produced by the timber processing industry. Wood is a renewable resource and therefore represents and energy source which will continue to be available into the future. Despite rising oil and gas prices, the price of wood pellets has been very stable for years and have even fallen slightly.