This set from 1955 might be connected, but it's about twice the size of a current washer dryer combo.

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Washer Dryer Combo Efficiency

When choosing between a separate washer and dryer or an all-in-one combination, there are some advantages and drawbacks that should be considered. One of the most obvious advantages of an all-in-one unit is the space savings. Since many of these units are about the size of a standard dishwasher and can fit under a countertop, they offer those with limited space a laundry option [source: Lee]. Since you don't have to run a vent outside, the ventless versions offer even more flexibility of positioning.

Along with space savings, there is also an element of time savings. Since these units have settings to let you both wash and dry at the same time, you don't have to worry about remembering to switch over the laundry. This may also alleviate the need for a second wash if you forget to switch over those wet clothes and they start to smell moldy.

Finally, all-in-one units can be energy savers. First off, the washing portions of these machines work much like front-loading washing machines. Front-loading washing machines typically use less water than traditional top-loading units; for this reason, these units also use less energy to heat the reduced amount of water [source: Federal Trade Commission, California Energy Commission]. Front-loaders also can spin more quickly and usually produce drier clothes at the end of the cycle, meaning less time in the dryer [source: Federal Trade Commission, California Energy Commission].

All-in-one units do have their drawbacks, or at least qualities that you should consider before purchasing one. While washer dryer combos are space-saving, that can mean a reduced capacity when it comes to load size [source: Lee]. Maximum load sizes for a combined wash-and-dry cycle can range from 6-10 pounds depending on the unit [source: LG Electronics, Ariston]. A cycle for an all-in-one unit can also take a longer time than stand-alone machines, ranging from about 2-3 hours [source: Lee, LG Electronics].

With both advantages and disadvantages, a washer dryer combo must be evaluated as any other appliance before making your final decision on the laundry system that's right for your needs. For lots more information on home appliances, see the links on the next page.