How to choose wood briquettes?
Don’t worry – it’s easier than you think! Our wood briquette guide will help you become a wood fuel expert in no time.
Wood briquettes and heat logs are interchangeable terms. They both describe a product made of wood by-products. These can be sawdust, wood chips or wood flour, using extreme pressure to form a block or log shape.
Different briquettes have different combustion properties, making some more suitable for certain stages in your fire’s life.
Some are great for lighting a fire; others are ideal for a nice hot flame during the day and others are designed to burn slowly at night.
Each stove is different depending on airflow, flue configuration and especially weather conditions. We only learned that there is no such thing as one “best” briquette for everyone. The best option is to try a few and see what suits you. Our sample kits and ready mixed pallets are perfect for this.
Generally speaking, a single good quality compressed log is equivalent to three or four traditional logs.
What makes a good briquette?
Compression: is the briquette dusty or brittle?
Compression refers to the pressure with which the wood is briquetted. High compression is better – these briquettes are denser and less dusty.
Low-quality machines, operating with a low degree of compression, produce cheap and dusty briquettes. We avoid them because they often deter people from smoking briquettes.
High-quality briquettes are manufactured using large, expensive machines working with very high forces to achieve a density of over 1000 kg / m3. The result is briquettes with a high calorific value that keep their shape and burn for a long time.
Caloric value: how much heat can it generate?
We compare the calorific value in terms of kilowatt-hours per ton (kWh / ton) as this allows easy comparison with other heating fuels such as coal, gas and oil.
As a guide, traditional logs have a calorific value of around 4,100 kWh / ton (depending on the humidity and tree species), while good quality briquettes have a calorific value of 4,800 to 5,000 kWh / ton, depending on the density and species of trees. (Note: 5500 kWh / ton is the same as 5.5 kWh / kg.)
The calorific value measures the heat output.
Ash content: How much ash will it produce when burned?
This is how much ash remains in the ash pan when extinguishing the fire. Virgin wood briquettes that have the bark removed produce significantly less ash than traditional logs. Some of our briquettes contain as little as 0.28% ash. For comparison, Bracken briquettes contain 4-7% ash.
However, some of the bark in the mix can increase the caloric value, and a large amount of bark in the briquette can help keep the furnace warm for longer periods, and even overnight. Our pure RUF Bark bricks contain approximately 4% ash and can burn for up to 12 hours. The bark contains more silica than clean wood, which creates ash.
Pure wood-burning ash is an excellent source of potash in your garden, so it can be safely added to the compost bin. Just make sure it’s completely cold first!
Moisture: how much water is in the briquette?
Wood briquettes generally have a water content (moisture content) of less than 10%. Most high-quality briquettes are dried to less than 6%.
By comparison, traditional logs are considered smokable when less than 20% and most winter-bought logs have around 30% moisture content. That’s a lot of water to evaporate and a very expensive way to buy it.
In general, the drier the better. The purpose of combustion is to generate heat, not to remove moisture, before the fuel produces heat. However, dry but poorly compacted briquettes burn too quickly. While they are often cheap, they are of low value compared to densely compacted but necessarily more expensive briquettes.
Extras: what else is in it?
The answer to that should always be “nothing.”
None of our briquettes contains additives (facilitating combustion) or binders (facilitating compaction). All our briquettes are bonded by the natural lignin released from the wood under the influence of intense compaction pressure.
Remember: if the wood content is dry enough, you do not need combustion additives. And if the heat log is tightly compressed, there is no need to add a binder. So a good quality briquette will not have and will not need any additives.
Product Standards: Are there any industry standards I should be looking for?
The highest quality briquettes are produced in accordance with European standards. They inform that the manufacturer complies with European standards for the composition, traceability, environmental sustainability and quality of the product. The standards to look for are ÖNORM M7135 (Austria) or DIN51731 (Germany). The equivalents of the EU and British standards are BS EN 15210-1 2009 and BS EN 15210-2 2010.
However, there are many briquettes of excellent quality that are not certified as the certification process is cumbersome and costly. Responsible manufacturers will always be able to provide the information we describe above, regardless of their certification.
While weight is not a foolproof way to purchase traditional logs, the consistency of the briquettes means knowing the price per kilo is really helpful.
Most packages weigh around 10 kg, but some packages are 5 kg, 12 kg, 15 kg, and others 20 kg. Of course, this should be taken into account when comparing prices between products. That is why we always mention “price per kilo” to facilitate comparison.
It may seem obvious, but don’t assume that more is better (I often have to comment “Ah, but there are four in this package and five in this package”); four briquettes in a 10 kg pack or twelve briquettes in a 10 kg pack; it’s the same energy, just four 2.5 kg each should last more than ten 1 kg each.
Again, while most pallets weigh 1 ton, some weigh more and others less. Take this into account when comparing prices and look for information on our “price per kg”.