Most people who smoke on a charcoal grill will use either wood chips or wood chunks to smoke with. However, wood pellets are more affordable; If you own a pellet grill, you'll almost always have them on hand too.
Truth be told, it is possible to use wood pellets in a charcoal grill.
To preface: This article is about using hardwood smoking pellets for smoking purposes. Charcoal grills use charcoal as their primary fuel source, not pellets.
When smoking on a charcoal grill, people typically use wood chunks. If they don't have wood chunks, they'll typically resort to using wood chips.
Wood chips are small pieces of wood that are roughly 1/4" thick and 1" in length. Pictured below are three post-oak wood chips next to a ruler for size reference.
People also use wood chunks which can range in size from 1-4" thick and 2-4" in length. Pictured below is a cherry wood chunk next to a ruler for size reference.
Either of these options are ideal for charcoal grills - however, if you own a pellet grill you might wonder if you're able to use the wood pellets from your hopper.
Truth be told, you can easily use wood pellets in your charcoal grill. You also don't need a ton to impart smoky flavor.
There are three main ways to use pellets in a charcoal grill:
In my opinion, putting the wood pellets directly on the charcoal is the best option - it's also the easiest.
All you have to do is take 5-10 pellets and put them on the lit charcoal and then close the lid. The result will be thin blue smoke that lasts for 45-60 minutes.
Note: I also added some wood chips because some folks question if they can add wood chips directly to the charcoal too.
The reason people are worried about adding pellets and wood chips directly to the lit charcoal is because they may catch on fire/combust initially - which is totally normal.
Wood chunks will even catch on fire, especially if the lid is open. When the lid is closed, the wood then smolders.
A lot of people and even products will tell people to soak wood chips in water - which is a complete waste of time. Soaking pellets on the other hand will entirely ruin the structural integrity of the pellet.
To get smoke you need a hot fire, oxygen, flame, and dry wood.
Here's what happens if you soak pellets in water for 30 minutes:
As you can see, soaking pellets in water isn't very fruitful.
Even still, on a charcoal grill the smoker needs to vaporize the water and then smolder the wood; All the water does is delay the wood from smoldering. If you were to open the lid after soaking them, they'd still combust and light on fire.
This is the same reason you shouldn't soak wood chips - just throw them on your fire and close the lid.
If you're someone who doesn't like the idea of the wood pellets combusting (again it's inevitable if you open the lid) you could fashion a tin foil packet or simply crumple up tin foil and leave a small opening for smoke to escape.
While I've done both of these before, I don't really find them super necessary. They definitely prevent the wood pellets or wood chips from combusting though, even if you open the lid.
I made both below using wood chips and pellets.
To create a "foil packet," you lay out a sheet of foil. Place the wood pellets to the left (where the wood chips are below) and then fold the tinfoil into a rectangular shape.
Next, poke a few holes in the top so that smoke can escape.
Another option is to simply lay out a sheet of tinfoil and then place your pellets on top.
You then crumple the tinfoil into a ball so that there is a small opening at the top; This way smoke can escape.
Either tinfoil apparatus is then placed on top of the lit charcoal.
Here's the tinfoil packet on the charcoal too:
If you're someone who doesn't smoke meat often, the above would more than suffice. However, if you do plan to smoke meat regularly, you could invest in a smoker tube or a smoker box to house your pellets in.
I've owned a few different smoker tubes and boxes over the year - pictured below is a really old pellet tube smoker that I bought 6 years ago.
While I definitely still use this smoker tube, the only time I do use it is when I'm cold smoking cheese or nuts.
If you're looking to hot smoke with a charcoal grill, you can use a smoker tube in much the same way to add smoky flavor.
Rather than putting the smoker tube on the coals, you can simply place it above the grill grates, away from your fire; This way smoke rolls over your food.
To reiterate, charcoal grills use charcoal as their primary fuel source. You shouldn't use pellets as a heat source.
Heating pellets are also different from hardwood pellets used for smoking in pellet grills. Wood pellets for smoking are hardwoods that are compressed into a uniform size and consistency.
They're designed for heat and smoke flavor.
Wood pellets for smoking are hardwoods like oak, cherry, hickory, pecan, apple, etc.
The pellets used to heat homes are made from softwoods, hardwoods, forest scrap, etc. Whatever is plentiful and can supply sufficient BTU to heat a home.
As a general rule of thumb, it's best to avoid using softwoods (evergreen or coniferous trees) like pine, spruce, fir, hemlock, cypress, and redwood.
Softwoods contain sap and resin (contain terpenes, the source of turpentine). As you can imagine, nobody wants to eat paint solvent, which is toxic when ingested.
Softwoods also have more air in their cell structure, meaning it burns very fast - which is the opposite of low and slow required for barbecue.