It is sometimes easy for us to underestimate the value of surfactants.
They not only clean our clothes but help reduce energy output. Surfactants (Surface Active Agents) reduce water surface tension, so it wets things more uniformly, seeping into dirty clothes fibres. Surfactants do another vital job too. One end of their molecule is strongly attracted to water (hydrophilic), while the other end (hydrophobic, is attracted to dirt and grease (also hydrophobic). So, the surfactant molecules (through the formation of Micelles) help the water to get a hold of grease and dirt, break it up, and wash it away. Water alone cannot clean clothes because it will not attach to molecules of grease and dirt.
Surfactant’s role in the conservation of energy
Washing clothes is part chemical, part mechanical, and part thermal – each weighs against the other. Less detergent means hotter water is required (thermal energy), or we need to wash for longer (more mechanical energy). Laundry detergents
specifically designed for low temperatures are either more concentrated or have a completely different “formulation” of ingredients that clean using less thermal energy. Cooler washing temperatures stop clothes shrinking or stretching out of shape and help colours last longer. All leading to a reduced environmental impact.