The appliance is either Energy Star Certified, or has an EU energy efficiency rating of A++ or A+++. This means it consumes around 20-30% less energy than is required by the minimum local standards for energy efficiency.
Aqua stop machines have a special mechanical system which cuts off the water flow into the tub if a fault occurs with the inlet pipe.
Whirlpool AWE 8840
Siemens iQ300 WM14N140
Front loading machines are good as you can use the space above and sometimes stack a dryer on top. In general front loading machines use less energy, using less water by only partly filling the drum and obtaining higher spin speeds which clean without requiring as much heat.
The device is designed a specific way so that it can be built into a cupboard.
With a transparent door you can look inside the machine and see what laundry is inside.
The slightly sculptured surface structure of the honeycomb drum creates a thin film of water or air which gently cushions and protects your laundry.
Dot matrix displays can show important text or graphics using a matrix of lights or mechanical indicators like the display on a calculator.
You can adjust the height of the machine which means that if the floor is uneven you can level it out.
A faster spin speed means you can get things cleaner with a lower temperature of the water. Using a fast spin also extracts water, meaning that the clothes come out nearly dry. Generally, anything over 1,000 rpm is very good.
With a lower noise level for washing you can worry less about disruption and may be able to do a wash at night or while reading.
With a delay start option you can schedule the machine to begin at a later time. You can also set the machine to wash at night if your electricity is cheaper outside of peak times.
More weight capacity helps if you want to wash something heavy like curtains. A traditional household machine can hold around 6kg, so with a machine much bigger you may waste energy using it when only half full.
Lower moisture levels after a spin mean that the laundry won't be as damp when you take it out. It will be lighter to hang up or take less time to dry in the dryer.
A really quick cycle can be a great option if you are in a hurry.
The detergent drawer is washed automatically to prevent a build up of old detergent.
The machine will let you know when it is finished with an alarm or even by playing a tune.