Use of heat pumps for energy efficient clothes laundry
Innovation pathway relevant to
Heat pump manufacturers
Clothes drying machinery makers
Washing machine makers
Background & introduction
Washing and drying of clothes and textile accessories can take up significant amounts of energy. A normal 7 kg washing machine requires a maximum power of 2000 watt – 2500 watt if used at full power with a hot water mix to wash clothes.
One of the ways to save energy is the use of heat pumps in washing machines and dryers. While heat pumps are recently explored and suggested for clothing dryers, only few companies have started incorporating heat pumps into washing machines.
What are the key sustainability benefits?
Heat pumps significantly reduce the need for electricity by about 25-30% and also associated costs.
How does this work?
A heat pump works as a closed loop system by heating the air or water using it to wash or remove moisture from the clothes and then reusing it once the process has been carried out.
For washing machines, the evaporator (cold side) of the heat pump is placed inside the air discharge duct. In the evaporator humid air is cooled down below the dew point. The temperature level of this waste heat is increased by the heat pump. In the condenser this heat is used to heat the central heating circuit of the washing machine.
For clothing dryers, rather than releasing warm, humid air through a dryer vent to the exterior of the home as a conventional dryer does, a heat pump dryer sends it through an evaporator to remove the moisture without losing too much heat. Making use of a refrigerant as part of this process means less electricity is used to generate heat.