Making charcoal

You really can make your own charcoal at home - even if you live in the suburbs! If you use the indirect method, which burns the gasses, and use a clean burning fuel (such as natural or LP gas) the emissions are mostly water vapor with very little smoke. It is not difficult to do and, even when burning waste wood to provide the carbonizing heat , the process requires less time and attention than barbecuing a rack of ribs in a wood burning smoker. 

Basic methods of making charcoal

Direct 

The direct method uses heat from the incomplete combustion of the organic matter which is to become charcoal. The rate of combustion is controlled by regulating the amount of oxygen allowed into the burn and is stopped by excluding oxygen before the charcoal itself begins to burn. This is the ages old method used by colliers to make charcoal in a pit, pile (clamp) or, more recently, in metal or masonry chambers (kilns). See the links below for more information. 

Indirect

The indirect method uses an external heat source to "cook" organic matter contained in a closed but vented airless chamber (retort). This is usually carried out in a metal or masonry chamber (furnace). The indirect method results in a higher yield of high quality charcoal with less smoke and pollutants and requires less skill and attention than the direct method.