I have been making small quantities in my wood stove on these cold nights. I usually get the stove going really good, and then at bedtime I shut the air off completely. The next afternoon it has lump in it ready to go.
I must warn though, be careful of smoldering embers in the lump that can statrt back up when the air returns to it. Make sure it is completely out.
Gustatus Similis Pullus
Large Big Green Egg
Charbroil Gas Grill