Your own charcoal
✱ There's no question that the market offers some very good options when it comes to charcoal. There are also some very bad ones, but that's not the topic here. Or maybe it does, because that would be a reason to make your own charcoal. Otherwise, your own charcoal has a bit of the character of homemade sauerkraut: you can proudly say afterwards: "I made this by hand, it's really something special."
But is it even possible to make charcoal yourself?
Do I have to build a charcoal kiln in my garden to do this? And isn't that a lot of work? In fact, producing your own charcoal is much easier than you think, provided you have access to enough decent wood. But before you start promising kilos of fuel to all your friends and acquaintances, let's first learn a few basics.
What is charcoal actually? Charcoal is charred wood. That sounds very trite, but it's pretty accurate. While burnt wood eventually turns to ash, a dry piece of wood that is charred in the absence of air leaves black chunks behind - charcoal. The classic method of production is the charcoal kiln mentioned above, a mound of earth that is built over a large pile of stacked wood. The wood is lit and then smolders for a long time until everything is "charred". This also produces wood gas, wood tar and wood spirit, so the focus is not always just on producing charcoal.
This is how simple a wood gasifier looks. Ultimately, it is two barrels standing inside each other with a chimney in the middle
Charcoal is now produced on a large scale in so-called retorts. Put simply, logs in a closed container are heated from the outside until the carbonization process starts. How long this takes depends on the temperature and the desired quality. Hard, dense coals with a lot of carbon require high temperatures and more time; conversely, coals produced quickly are less dense, have more gas components and less carbon. This explains why high-quality coals burn hotter, smoke less and for longer than discount products. But good coal also costs more.
Charcoal kilns, retorts – none of this sounds like something you could do in your own garden. But there is another way: using a process in which charcoal is actually a by-product, namely the wood gasification process. As already mentioned, carbonization produces wood gas, a mixture that is flammable. It consists mainly of carbon monoxide, hydrogen and methane. There are modern high-tech wood gasifiers that can supply buildings with both heat and electricity in combined heat and power plants (CHP plants). There are corresponding devices for heating single-family homes. In times of scarce raw materials during the war and afterwards, cars also had wood gasifiers, and instead of petrol, the engines burned wood gas. There are also very simple variants of the wood gasifier. In principle, this is a barrel with a chimney in the middle from which the wood gas can be burned off. And it can be closed in such a way that the wood burns or chars with a significantly reduced air supply. You can build such a gasifier yourself. But if you don't want to go to the trouble, you can find it in this country by looking for Terra Preta. This is actually a charcoal-containing soil from the Amazon region, and some companies offer it for the domestic market: substrates and charcoal (vegetable charcoal) to enrich the compost. And also wood gasifiers to make the charcoal yourself. Our wood gasifier - a relatively small model - was provided to us by TriaTerra, for example, who are all about Terra Preta. Depending on the size of the gasifier, prices range from less than 100 euros to over 1,000 euros.
The fire is lit with oxygen and a few small pieces of wood
During pyrolysis, the wood chars; the wood gas burns at the holes in the chimney
Once all the gas has burned, the charcoal is extinguished with water. It must then dry
And the coal also provides enough heat; you can grill a few steaks in our Icon
The homemade charcoal burns evenly and, despite its small grain size, is quite persistent, and is also smoke- and odor-free
It is quite simple to use. First, a fire is lit in the inner barrel using small kindling and oxygen. If it burns well, the oxygen supply is reduced by the outer barrel; the primary air now essentially flows through the inner chimney and sucks in the wood gas, which in turn draws more air through the chimney and away from the wood as it burns. This causes the wood to char and not burn. Once the gas has burned, the garden hose must be used. The charcoal is extinguished. Then it is left to dry and can be used for the grill. Now, of course, the question remains whether the end product is even suitable for the grill. We used well-dried beech wood for our charcoal, which incidentally came from our own garden. For the wood gasifier, we cut two larger logs into eight smaller ones, which in the end - a disadvantage of the small gasifier - also resulted in rather small-grained charcoal.
Ideal for grills like the Lotus, but also usable in the Monolith Icon, for example, in which we tested it. And surprise: despite the really simple production, our charcoal is very high quality. At the beginning, some residual moisture evaporates, but then the charcoal really kicks into high gear; odorless, smoke-free, without flames. The wood is really very cleanly charred, much better than some products on the market. And despite the relatively small grain, we reach a temperature of 400 °C in the grill. And long enough that we can easily grill a couple of decent steaks and sausages for a family of four. In conclusion, if you don't have access to good charcoal, but do have access to good wood, making your own is a real option. The effort is limited, the result is good. And, as mentioned at the beginning, it has the aspect of being handmade.
By Markus Mizgalski