The small town of Bern, Kansas (population approximately 200) was selected evaluate the energy and water savings of high-efficiency, horizontal-axis washers. During phase I of the study, 103 clothes washers in the town and surrounding Rural Water District were instrumented so that data on customer profiles, laundry habits, laundry throughput (loads and load weight), and energy and water consumption could be measured. Following a two-month data collection period, all of the washers were replaced by new, h-axis clothes washers, and the experiment continued for an additional three-month period. Overall, detailed data were collected and analyzed on more than 20,000 loads and nearly 70 tons of wash done by all of the participants over a wide range of real-world conditions.
Overall, it was found that the changeover to the h-axis washer reduced the average water consumption from 41.5 gallons/load to 25.8 gallons/load – a water savings of about 38%. The h-axis washer’s energy consumption including washer energy and hot water energy fell by 58% due to hot water savings and the impact of a highly efficient motor in the h-axis. The remaining moisture content of damp loads removed from the h-axis washers was, on average, 7% lower than for loads removed from participants’ phase I v-axis washers, and this would tend to improve the energy savings from the changeover still further.
The data and subsequent analyses also showed that across all loads, temperature settings, use of detergent and other additives, participants found the cleaning performance of the h-axis technology to be generally superior to their phase I v-axis washer irrespective of its age. Participants seemed to adapt easily to the h-axis design, and laundry habits (average load weights, detergent use, how loads were dried, when loads were washed during the week, wash/rinse temperatures and other factors) remained largely unchanged from phase I to phase II.
These findings demonstrate convincingly that the tumble-action technology (h-axis design) is much more energy and water-efficient than the technology present in clothes washers found in the field today. Taken together, these findings suggest that a changeover to h-axis technology
delivers large savings in energy and water to the customer with an improvement in cleaning performance and utility.
Oak Ridge National Laboratory
U.S. Department of Energy