Many automated indoor composters can accommodate up to 120 pounds (55 kilograms) of waste per month [source: Nature Mill]. However, along with the benefits of these units also come a few drawbacks. There are the usual maintenance issues, such as strong odors, additional energy usage and costs, and loud noises during operation. Plus, you need a compact way to house all the necessary parts, in addition to an accessible yet out-of-the-way place to store it.
Most automatic indoor composting systems are encased in some sort of stainless steel and aluminum combination, though many also feature plastic elements (often made from recycled materials). Newer models are quite sleek in their overall design, resembling a large, modern coffee pot, espresso machine, or slow cooker. Units tend to weigh between 10 to 20 pounds (4.5 to before composting. They generally take up about as much space as a kitchen garbage can (or about 20 inches in height and depth and 12 inches wide), though some models can actually be installed in cabinets, similar to trash compactors that slide in and out to blend in with your cabinetry.
Automated composters are primarily intended for indoor placement within a kitchen, laundry or utility room, or garage, but if you don't have room for one, many can actually be used outdoors if you choose. If you do plan on using one indoors, you might consider one that offers thermal insulation along with airtight sealing to prevent one of the main drawbacks: foul odors escaping into your home.
Wherever you use your composting system, combating and controlling the smell they produce can be tricky. If an overpowering odor is present, it's usually a sign that the system needs more turning and aeration. The automated system should maintain aeration on an ongoing basis, but you may need to check the unit to be sure it is working properly. You might also consider using carbon filters within indoor units to keep the smell in check.
Another potential drawback to consider is the noise the systems make during operation. Whirring and snapping sounds at the onset of the composting cycle are typical, along with humming from the air pumps. Most units produce minimal noise once materials have been heated and the actual process is underway. Before you buy one, you might want to read product reviews to see what other people have to say about the noise particular units make.
Lastly, as with any other home appliance you own, you also should be mindful of general upkeep and maintenance. Many machines start out with a minimum one to three year manufacturer's warranty, though there are options for extending or additional coverage. You'll also need to know how often to change the air filters and carbon filters, as well as when to empty and clean the system.
If you think an automatic composter might be something you'd like to add to your home, read on to find out what it could cost you.