How to make Charcoal - The Trewan way
Making Charcoal at Trewan is another one of those things we have been doing for years, it's a well-practised process and this year a chance for Joseph and myself to learn the ropes!
Generally once a year and around this time (March/April) we will have a charcoal burn. This time around I annoyingly insisted on capturing the process, I thought it might be an interesting look behind the scenes at a piece of Trewan that is rarely seen. It's quite unique to be able to offer campers charcoal for their BBQ's that started life as a tree on the very same site.
Selecting trees is not a simple task but luckily we have Mike around who is a trained Aborist, not every team has one of them! Every year we survey and track the health of our trees making sure anything close to the camping fields or buildings is safe and strong. With a site of our size, it's a safe bet that over the winter a tree will need to come down, or more rarely, a storm might force one over. Importantly we never fell a tree for charcoal, it only comes from wood that has fallen naturally, or from a tree that was approaching its end and we have removed limbs for safety.
Firstly to make your charcoal, you will need;
- 5 tonnes of wood, this year we have selected a heady blend of Ash and Oak, classic stuff.
- 1 huge charcoal burner
- 2 cardboard boxes
- Some paper from the recycling
- A lighter
Firstly the burner needs clearing and the lighting bed constructed. To make the bed we arrange logs creating 4 channels to the centre which we then stuff with paper. This means once lit at the edges the fire should spread over the base of the burner before working its way through the rest of the wood for a nice even finish.
Click the side arrows for more pictures through this page.
Once the bed is constructed we stack the burner full of wood, this is is one of those jobs where you balance doing the best possible (perfectly tesselating the logs together) with time. This means you should end up with a tightly packed burner of wood with some space for air to flow and the fire to spread. Once that's complete it's time for the lid to go on and get out the lighter!
Lighting the thing is a critical point of the process, you want to make sure the whole lot is burning so you can get the most yield, a cold patch certainly won't help. To do this we start on the side sheltered from the wind as it will burn slower, then make our way around to light all 4 channels. We then closely monitor the fires making sure they are all spreading and helping them on with a waft if they are lagging behind.
Next, we start to process of controlling the airflow. This is really what makes it charcoal and not having a bonfire. Quick pause for some science.
The basic idea of making charcoal is to burn off all the impurities and water in the wood to leave the real 'fuel' behind, this is done by burning the wood at a high temperature then starving it of oxygen.
To control the airflow we build up soil around the base of the burner. The timing and choice of which sides to block first allow us to also control which parts of the burner get more airflow, letting them catch up with faster burning sections. Once we have covered the base the chimney's go on for even better control of the airflow, and we let the whole thing burn for about 28 hours. During this time white smoke is produced, this is mainly steam with sap and bark also burning off, leaving us with the good stuff.
Every 6 hours the chimneys need changing position to keep an even burn, luckily Matt volunteered for the 12am and 6am shift and Joe and I escaped with our sleep undisturbed.
The next day we checked the burner and seeing that the smoke had gone clear we knew it was time to shut off the airflow, starve the fire of oxygen and let it cool. Something that would take over three days! The last thing we wanted to do was take the lid off for there still to be a flame, this would have lead to a very large BBQ...
Next up was getting it out and bagging it up. For this, we used elbow grease and a 'Riddler' constructed by my Grandad. The Riddler's job is to jostle the charcoal down a gradual funnel to a bag. Halfway down the funnel, the charcoal moves over chicken wire and the smaller bits are separated out. It's also a chance to provide some quality control and make sure any unburnt wood doesn't make it through.
Happily, this was a great burn and we got just over 150 bags of charcoal ready for the shop this summer. Nice to know if you need it we have it. No nasty stuff in there, just Ash and Oak reduced down so it burns clean and hot, perfect for the barbie!
Here is a before and after of the grubby gents involved, now we know how we look with eyeliner on...