How does a washing machine use water and energy, and what do the settings mean?

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1. 1

   Promoting energy conservation through attention control and construct activation: A field test at a campus laundry.

   PloS one (Buzinski et al.)Published Apr 8, 2026Checked Oct 17, 2026

   “Increasing the frequency of laundering in cold water has been demonstrated to reduce energy consumption, but heated water laundering rates remain high. This is particularly true in wealthy, western nations. This paper describes an individual-level, situated intervention utilizing attentional control and construct activation to motivate cold water laundering. In Study 1, we report the first direct observational study of laundering in a field setting, finding that (a) only 21% of laundry loads were washed with cold water, and (b) behavioral, normative, and control beliefs were associated with laundering in cold water. In Study 2, we report an experimental field test of an intervention designed to increase rates of cold-water laundering. The intervention significantly increased cold water laundering (57%) compared to a control condition (25%). We also tested mediators of the intervention and laundering behavior association and observed that control beliefs fully mediated the relationship. We discuss the theoretical and practical contribution of these studies to the environmental psychology and motivational science literatures.”

2. 2

   Household Laundry Appliance Resource Consumption and Operation Dataset.

   Scientific data (Jasiūnas et al.)Published May 16, 2026Checked Oct 17, 2026

   “The user behaviour is often overlooked in existing datasets. To address this gap, the household Laundry Appliance Resource Consumption and Operation dataset (LARCO) is presented: a comprehensive, open-access dataset capturing detailed operational and environmental data from washing machines and dryers under laboratory and household conditions. The dataset includes multivariate time-series recordings at 1 Hz (and higher for vibrations and audio), covering a range of load sizes, programme settings, and ambient conditions. Laboratory data provide ground-truth measurements under controlled conditions, while household data capture real-world usage variability. Each sample includes energy, water, temperature, and humidity measurements, associated with the corresponding metadata. LARCO enables studies on appliance efficiency, user behaviour modelling, and personalised energy feedback. It supports the development of more effective strategies to bridge the gap between labelled and actual appliance performance, promoting more sustainable energy use.”

3. 3

   Washing machine (Wikipedia)

   WikipediaPublished Oct 15, 2026Checked Oct 17, 2026

   “A washing machine (laundry machine, clothes washer, or washer) is a machine designed to launder clothing. The term is mostly applied to machines that use water. Other ways of doing laundry include dry cleaning (which uses alternative cleaning fluids and is performed by specialist businesses) and ultrasonic cleaning. Modern-day home appliances use electric power to automatically clean clothes. The user adds laundry detergent, which is sold in liquid, powder, or dehydrated sheet form, to the wash water. The machines are also found in commercial laundromats where customers pay-per-use. Before the invention of washing machines and indoor plumbing, clothes had to be washed by hand in a multi-step process that often occupied an entire day of work, plus drying and ironing. The first English patent under the category of washing machines was issued in 1691. Electric washing machines were advertised and discussed in newspapers as early as 1904, and the first automatic washing machine was introduced in 1937.”

4. 4

   Efficacy of personalized feedback in encouraging sustainable washing behavior: evidence from a pilot study in Germany.

   Frontiers in psychology (Höpfl et al.)Published Jan 28, 2025Checked Oct 17, 2026

   “Asynchronous structured interviews were conducted at the end to explore participants' perceptions and washing behaviors.ResultsWhile we found effects for the feedback manipulation, we found no differences between user clusters in individual washing behaviors. Furthermore, participants qualitatively reported habitual changes, feeling more knowledgeable about the monetary impacts of specific washing programs and temperatures, and wished for a more accessible preset time function. Most participants expressed willingness to switch to a dynamic energy price if it translated to significant cost savings.DiscussionOur findings may support the notion that individualized behavior change strategies are promising. In general, these strategies should be easily applicable, cost-effective, and promote habits to be exerted regularly. Arising methodological limitations suggest further research in this domain. From an applied perspective, our research provides valuable insights for designing products, services, and regulations by governments and companies, empowering them to develop more effective strategies for reducing energy consumption.”

5. 5

   Microbial Colonization, Biofilm Formation, and Malodour of Washing Machine Surfaces and Fabrics and the Evolution of Detergents in Response to Consumer Demands and Environmental Concerns.

   Antibiotics (Basel, Switzerland) (Osta-Ustarroz et al.)Published Dec 18, 2024Checked Oct 17, 2026

   “Microorganisms also adhere to different types of clothing fibres during the laundering process as well as a range of sweat, skin particles, and other components. This can result in fouling of both washing machine surfaces and clothes and the production of malodours. This review gives an introduction into washing machine use and surfaces and discusses how biofilm production confers survival properties to the microorganisms. Microbial growth on washing machines and textiles is also discussed, as is their potential to produce volatiles. Changes in consumer attitudes with an emphasis on laundering and an overview regarding changes that have occurred in laundry habits are reviewed. Since it has been suggested that such changes have increased the risk of microorganisms surviving the laundering process, an understanding of the interactions of the microorganisms with the surface components alongside the production of sustainable detergents to meet consumer demands are needed to enhance the efficacy of new antimicrobial cleaning agents in these complex and dynamic environments.”