Washing machines consume large amounts of water and energy, so the key to selecting the right one is to purchase the most energy efficient model that suits your lifestyle and space. In terms of lifestyle, think about how often you use the washer and what you wash.

Now, when you want to use your washer and dryer often, it's best if you buy one with a stainless-steel tub. High-grade plastic tubs or porcelain-coated ones will work fine for those who wash less frequently. For those with limited space, there are stacking washer-dryer units in either full-size or apartment-size capacities. Another important thing is that you must get a dryer that matches your washer's capacity.

Think about what you will use them for. If your wash includes a variety of fabrics and levels of dirtiness, choose a machine that offers specialty cycles such as delicate and extra soak, as well as one for a second rinse. You need multiple water-level settings to get efficient washing for different load sizes. Some machines can boost water temperature to sanitize a load. Automatic temperature regulators are a must in cold climates, so that water comes into the machine at a constant temperature, depending on the setting.

The two common types of washing machines are top-load models and front-load washers. Top-load washers allow you to access the wash tub without bending. These models must be set side-by-side with the dryer. While these machines cost less initially, they are also less energy-efficient in the long run.

Front-load washers are recommended for its energy efficiency, and indeed it has been steadily growing in popularity because of this feature. These models use only up to one-half of the water that is usually needed for a top-load machine. This also means less time and energy used for heating. Clothes also come out needing less time in the dryer because the agitators spin a lot faster. They are usually more expensive than top-load washing machines, however, and you may need to buy special detergent for some models.

When selecting a dryer, the capacity you choose should complement your washing machine's capacity. A washer with a 3.5-cubic-foot capacity, for example, requires a 7-cubic-foot dryer capacity. You can always buy a stacking model that can fit in a closet if space is a problem.

Dryers are powered by either gas or electricity. Gas models are typically more costly to purchase, but it will prove to be more energy efficient and economical in the long run. By law, dryers must have at least one automatic-drying cycle, but the best dryers include moisture sensors, which automatically shut down the machine whenever the moisture level in the drum drops below a certain point. Other nice features include a cool-down cycle, which keeps the clothes wrinkle-free, and a damp-dry cycle that allows garments to be prepared for ironing.