Charcoal problems

[SitkaSpruce]

We made charcoal for the first time this year on a small scale. We used mainly seasoned holly and a bit of larch to fill the container. We produced lovely charcoal but find it gets v hot and once fully ignited doesn't last very long. We've had similar problems with commercial uk produced charcoal. Is there any way of making a slower burn, cooler charcoal? Is it down to species used or method? Any useful experience gratefully received!

[Wendelspanswick]

The trick with charcoal fired stoves is to restrict the airflow. I have made a number of charcoal fired stoves to go in vans and boats, modelled on the Pansy charcoal heaters and they have a 1" flue with a 1" air intake that can be closed off completely, it will still stay going by drawing air down the flue and will burn for upto 16 hrs on a single filling.