Charcoal Reuse

Kjunbob

Having completed several cooks and overcoming a few mistakes that I made at first by not putting enough charcoal in up front and running out of fuel, I have been putting much more in at startup.  

And therefore at the end of the cook, I always have some left over for the next cook. I am wondering, when starting the next cook should I always put in some fresh charcoal, given that most of what is in the egg is from prior cooks.  Or will the "old and partially burnt" charcoal be sufficient if the quantity is sufficient for the next cook. 

Any advice here?  Thanks!

Shiff

I always fill up my egg to near the top of the fire ring every time I cook.  I first stir the old coals to get any ash to fall into the bottom, then dump in new on top.  I empty the bottom part every 4 or so cooks to keep a good airflow.  I don't so any sorting or removal of the old or new lump.  Takes about 5 minutes to get everything ready for a new cook.

Jeepster47

The used lump will not have as many BTUs as fresh lump ... it's less dense 'cuz it's already given up some energy.  There's no magic formula, just remember that a fill to the top of the firebox with used lump will yield less time than the same volume of new lump.

Based on the next cook, sometimes you'll have enough and sometimes you'll have to add.  Just like your bottom vent setting, experience is the best teacher.

I hate to run out of fuel during a cook, so will always overfill ...

jtcBoynton

No need to add "fresh" if there is enough left from the last cook.  "Partially burnt" is not the best description.  The charcoal is either burnt (and gone) or not burnt.  What is left is unburnt charcoal. It is good to go carbon (with all the VOCs already removed from the previous cook).  Only issue to watch is if the size of the lump is so small that it gets packed in the fire bowl so that airflow issues may arise.  

XC242

Either way works fine. In general one can say re-using the old charcoal will mean less time will be spent waiting for VOC's to burn off. Also old charcoal might start up a little quicker. Bottom line is you'll likely be cooking quicker than if you add new lump. One thing to watch for is if your previous cook was direct and you had a lot of fat and juices getting into the burning lump you should take a little extra time on the next cook to let that stuff burn off.

pab

From my experience if I am cooking something quick and simple like sausages, chicken breasts and the like, if there is enough charcoal from the last cook I don't always add more. If I am cooking a pizza and I am heating a pizza stone I ALWAYS add more. If I am doing a low and slow I remove the partially used coals, add a load of fresh lump and put some of the removed charcoal back on top of the new. YMMV

chuckytheegghead

I usually top off with new new lump and stir and it in. 

FATC1TY

just keep adding.. stir it up well if you use the stock crappy fire grate. air flow is the key.. the old lump starts up faster, but depending on heat and length of cook, I alway add back something unless its stull full from previous cook.

3andsomedust

I grill direct much more often than I smoke so I fill up the fire box with as much new charcoal as possible (probably 15 lbs)  I have an XL and can normally get at least 5-6 grill cooks out of 1 load of lump.  I intentionally NEVER add any new charcoal to my existing charcoal unless its obvious I'm going to run out because I don't want to have to wait 20 extra minutes to burn off the VOC's with every cook.  I also try to not even stir / mess with the existing charcoal before a new cook since the airflow channels are already set from previous cook.  My goal after burning off VOC's from the initial load of lump, is to get up to cooking temp as fast as possible for the next several cooks which is usually 8-10 minutes after hitting it with a weed burner to light the existing lump.....adding new lump every cook would completely defeat my purpose.  If I had to wait and burn off VOC's before every cook I probably wouldn't use my egg honestly.