Here, you can find the answers to the most frequently asked questions about HD pellets and HD pellet technology. These FAQs are regularly updated and expanded (version as of 08/06/2016).



Are HD pellets also standardised in accordance with DINplus, EN14961 and/or ENplus?

Yes, because all HD pellet manufacturers are also certified in accordance with ENplus and/or DINplus. The HD pellet technology improves the pellet properties within the quality specifications in these standards.

Are there additional key quality criteria for HD pellets??

The HD quality system builds on the existing certification programmes. Every HD pellet manufacturer must always be certified in accordance with the requirements of DINplus or ENplus-A1. In addition, stricter target values apply in the HD quality system, with abrasion values of <1.0%.
EN14968 defines a limit value of max. 2.5%. Pellets with abrasion values of significantly more than 1.5%, and particularly for around 2.0%, can cumulatively lead to problems in small-scale furnaces in practice.

Do HD pellets burn more cleanly and efficiently than conventional pellets?

Wood pellets with a high target length ratio and the fewest possible short pellets and fragments burn most cleanly. HD pellets have a significantly higher proportion of pellets in the optimal length range. In bench tests by well-known scientific institutions, HD pellets have been shown to burn more leanly and efficiently in comparison with conventional pellets, with reduced CO emissions.

What does the abbreviation “HD” actually stand for?

The abbreviation “HD” stands for Helix Design. The explanation for this is that the HD system is based on the benefits of a helix-shaped cutting and guidance system when cutting the pellets to length and channelling them out.

Are HD pellets also suitable for vacuum systems?

Yes, without limitation. Because the HD system can guarantee that there are no over-length pellets. Thanks to the HD pellet technology, blockages resulting from over-length pellets in vacuum systems are a thing of the past.

Are HD pellets also suitable for screw systems?

Yes, because HD pellets have significantly fewer short pellets, fragments and dust. As a result, good flow properties are guaranteed.

What is the thermal value for HD pellets?

The thermal value is approx. 17.5 MJ or 5.0 kWh per kilogram of wood pellets.

Does the HD technology change the weight by volume of the pellets?

No, the weight by volume is not affected by the HD pellet technology.

From whom can I as a consumer find out where I can get HD pellets?

On this website, under the menu item "Find HD suppliers" you can see the HD pellet manufacturers and retailers in a map and list view. If there are no suitable suppliers for you, simply ask your current supplier or retailer for HD quality wood pellets. Every certified retailer is supplied with HD pellets by the HD manufacturers.

Are there also additives used with HD-Pellets?

No – the superior HD-Quality exclusively based on the technical lead of the HD Pelletstechnology. The use of additives is not intended and not necessary.

How do I convert from heating oil to pellets?

If you want to convert oil heating to pellets, simply multiply the previous oil consumption in litres by 2. This will give you your rough future pellet requirement in kg. Example: Previous heating oil consumption: 2,000 litres = expected pellet requirement: 4,000 kg.

Where can I find a price comparison with gas and oil??

You can find such a price comparison here: hier.

What kind of pellet heating systems are there??

There is a broad selection of different performance classes, types, models and burner systems for both pellet boilers and pellet furnaces. You can find an up-to-date list here. hier.

How large does my storage space need to be?

An average storage space height of around 2 metres results in a storage density of roughly 1 tonne per square metre. Ideally, you should be able to store 1.5 times your annual requirement. For an annual requirement of 4 t, you would therefore need around 6 square metres of storage space.

How much space is required for a tonne of pellets??

For an average weight by volume of 650 to 700 kg, the storage space requirement is roughly 1.5 cubic metres per tonne.

Where can I find more details and suppliers for pellet storage?

You can find everything you need to know at the German Pellet Institute.Deutschen Pelletinstitut.


Does the manufacturer’s HD certificate replace DINplus, EN14961 and/or ENplus?

No, because certification in accordance with one of the established standards is mandatory for all HD pellet manufacturers. The HD quality guidelines build on the existing standards and augment them for the specific product.

Where are the differences and what are the additional quality requirements for HD pellets??

There are clear requirements for the length distribution of the pellets which can only be achieved with the HD pellet technology. The applicable European standard and the ENplus and DINplus standards only define the maximal permissible pellet length.

The mechanical strength of the pellets must be greater than 98.7% in regular operation in accordance with the HD quality guideline. Since it is a natural material, intermittent deviations up to a maximum value of 98.5% are permissible. For normal ENplus A1 pellets, a limit value of 98.0% applies.

What are the benefits of the HD technology for the manufacturer?

With the HD technology, the proportion of pellets in the ideal length range is significantly increased. The system guarantees that there are no over-length pellets. Alongside the marketing and combustion-related benefits, there are also benefits for the producers:

  • Increase in the efficiency of the pressing technology thanks to a careful process for cutting to length and therefore lower proportion of material from the screening technology and aspiration for multiple processing
  • Lower proportion of end surfaces and reduced generation of fine particles upon each manipulation of the pellets
  • Less damage to the surfaces of the HD pellets and fewer pellets per tonne
  • Guarantee of no over-length pellets with no additional shredding technology
  • Millimetre-precise adjustment of the pellet length
  • Very consistent pellet bulk weight

Alongside the product-specific benefits, HD quality pellets are also more optically appealing then conventional pellets.

Is the HD pellet technology available for purchase?

No, but license agreements for use of the HD technology and the “HD” registered trademark can be agreed.

What pellet presses is the HD technology suitable for?

In principle, the HD system can be used for any type of round die. The following press types are being/have been successfully converted:

  • CPM 7930-4
  • CPM 7932-5
  • Salmatec Maxima 840
  • Salmatec Maxima 700
  • Andritz PM30
  • Andritz BioMax
  • Bühler RWPR 900
  • Münch RPM 520/80

Is the conversion to HD technology a significant change within the meaning of the Machinery Directive 2006/42 EC?

No, it is a tool change and therefore not a significant change within the meaning of the Machinery Directive 2006/42 EC. This has also been confirmed by a DEKRA report.

How long does it take to convert a press to the HD technology?

It differs depending on the type of press and varies from approx. one hour to one working day per press.