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Things to consider when buying wood chips

What to consider when buying wood chips

If you want to buy wood chips, it is not only the price that decides, but also the quality. This is defined, among other things, by the water content, which actively determines the calorific value and the storability of wood chips. Furthermore, one should consider the bark content, which is also an important criterion for quality and combustibility.

In this report you will learn everything you need to know about buying wood chips.

Overview of our wood chip boilers

What does wood chips cost?

If you compare the prices of wood chips and oil in the last 10 years, you will see that during this period wood chips were about 57% cheaper than oil. So with a wood chip boiler you can heat much cheaper.

The price development of wood chips

Price fluctuations when buying wood chips are also due to seasonal and regional fluctuations. Therefore, the prices for wood chips are to be understood as guide prices.

TIP: Buy your wood chips rather in the summer months. Here the demand is lower. The larger the purchase quantity, the lower the price will be.

What to look for when buying wood chips?

As briefly mentioned above, the water content is an important criterion for the quality of wood chips. Directly after felling and crushing, the water content is approx. 50-60%. If you want to store and burn the fuel, it should usually be between 20-35%. The average calorific value of wood chips is 4 kWh per kilogram. Tree species and water content are also crucial here.

One can lower the water content by storing the wood chips in a dry place for a longer period of time or by using wood chip drying equipment.

The bark content is another quality criterion. The lower the bark content, the higher the quality of the wood chips. The quality of wood chips is precisely defined in DIN standard EN 14961 (ALT ÖNORM M 7133).

Stückholz und Hackschnitzel | Biomasse | Hargassner

How much space do wood chips require?

The required volume of wood chips is specified in cubic meters (rm), solid cubic meters (fm) or bulk cubic meters (srm). 1 cubic meter refers to the volume of a cube with a length of one meter. Height x width x length is equal to 1 meter. Intermediate spaces are not taken into account here. If these are taken into account, one speaks of solid cubic meters. We speak of bulk cubic meters when we refer to a loosely poured quantity of wood.

1 bulk cubic meter = 0.65 cubic meter = 0.5 solid cubic meter

Wood chips require about twice as much space as logs and four times as much space as pellets.

The typical areas of application for wood chip heating systems are agricultural or wood-processing businesses, commercial enterprises or public buildings as well as micro & local heating networks.

Rule of thumb for the storage room:
Per kW of heating load = approx. 2 m³ of storage space for an annual requirement.

If you have a smaller storage room, you simply have to refill it more often. A favorable location is right next to the boiler room. The structural fire protection requirements must be complied with. Electrical installations that are absolutely necessary should be explosion-proof.

Depending on the circumstances, different storage and delivery systems are possible for feeding wood chips into the store.