I've talked to a lot of people who throw away their used charcoal after making sure it is completely out. I had to know if they are wasting their money and adding to the landfill unnecessarily and devised a test to find out if using your old charcoal is worth it.
Did you miss our previous article...
https://greatcookingtips.com/grilling-tips/we-made-the-entire-innout-secret-menu-and-this-happened-sam-the-cooking-guy