The debate over charcoal versus gas can get heated, and adding newer electric grills in to the mix only fuels the fire. The one simple thing you need to know is that choosing the best fuel type—charcoal, gas, or electric—for you is primarily a matter of taste and convenience. Beyond that, a few other factors can help you make the right decision.
As a general rule, the more convenient a grill is the less smoke flavor it produces. An electric grill is the easiest to use but doesn't have that real fire flavor, while hardwood charcoal fires give you the best flavor but can be the hardest to deal with. The question to ask yourself is, do you want a fast and easy meal, or are you looking for something more? Hardcore grillers and barbecue cooks treat this style of cooking much more like a hobby than just a way to cook a meal. Of course, charcoal really isn't that complicated and with practice can be just a reliable as using a gas grill.
The authentic smoky, off-the-fire taste of grilled foods is strongest with the original heat source: wood. And charcoal, of course, is made from wood. As you move to electric units, there is very little of this flavor left. In fact, many electric grills add virtually nothing to the taste of foods. However, the simplicity of flipping a switch and grilling can't be beaten.
On the subject of taste, in a study conducted a while back participants were presented with hamburgers and steak cooked on gas and charcoal units. No one could tell the difference between the charcoal or gas when it came to the hamburgers, but they could tell the difference with the steak. The charcoal grilled steak had a distinct smoke flavor. If you are going to be cooking larger items, particularly items that benefit from slow roasting and you want a deep smoke flavor, charcoal is the only way to go.
Space and Safety
To decide what kind of grill is right for you, consider where the grill is going to sit. A small patio or covered area is not the place for a large charcoal grill, due to the heavy smoke during startup and the likelihood flare-ups during cooking. Electric grills produce no flare-ups and are safer in smaller areas. Gas grills do produce flare-ups and need to be away from any structure to avoid those pesky house fires.
Another thing to consider is how you plan to grill. If you want to come home from work and throw a couple of steaks or chicken breasts on the grill with virtually no hassle, then an electric or gas unit might be what you are looking for. These heat much faster and have the convenience of a general cooking appliance. On the other hand, if you like to relax on a weekend and have some drinks or socialize while you fine-tune your fire or slow-roast a chicken, charcoal gives you a lot more to work with.
Finally, there is the issue of cost. Gas grills are generally more expensive than electric or charcoal; charcoal being the cheapest. If you don't want to spend a lot of money up front, then charcoal might be the answer. However, charcoal is a more expensive fuel and may cost more in the long run. Electric grills typically are the cheapest to operate, and you never have run out to the store for more fuel.
Gas grills can be fueled by natural gas or propane. Because natural gas comes from your home hookup and requires no additional tank, it's much cheaper and more convenient than using standard portable propane tanks.