Energy or detergent savings is very low on my list to think about. I wash small loads and in hot or warm water. I do not like having a big load of laundry to deal with. I wash two to three small loads a day. One for towels, linens, etc. One of the clothing DH and I wore the day before and one of have to be white items if any. I never have laundry piled up needing to be washed doing three small loads a day. It works for me.