One change I’ve made recently as I attempt to “lean” my everyday life is to run the dishwasher more often. This seems stupid at first glance, since it costs money to run the dishwasher so more running = more money. In addition, running the dishwasher more frequently (in my case, every night) increases the odds of running it without a full load.
So why am I doing it? Here are some reasons for more-frequent dishwasher runs from a lean perspective:
1. Reducing defects, which are one of the seven muda (types of waste) identified by lean production methods. When we let the washer get over-full, some of the dishes inevitably don’t get fully cleaned and we end up having to wash them again in the next run. Cutting down on the load size by upping the frequency largely fixes this.
2. Reducing inventory, another of the seven muda. When we run the dishwasher less often than once a day, we often run out of space and end up having to stack dishes in the sink or on the counter as they wait for space in the washer to open up.
3. Reducing waiting (yes, another of the seven muda). If we can only run the washer when it’s full, we inevitably end up waiting around, especially if we are eating out a lot, to finally get it filled up. In the meantime, there are dishes, cutlery, etc., that we cannot use because they aren’t clean.
These wastes are common in processes where you haven’t been able to level the demand. Whenever you are dealing with a process where demand unpredictably rises and falls, you will inevitably have some times when resources are sitting idle and other times when you don’t have the capacity to meet expectations. These swings, and our attempts to deal with them, inevitably lead to more defects, inventory, and waiting.
One of the goals of lean production methods is to create a more-level demand for the process so these wastes can be reduced. There are various ways of doing this (such as the heijunka box, which I will discuss in a later post), and all of them try to level demand while still being extremely sensitive to the marketplace and the needs of the customers. It’s no small feat.
In the case of my dishwashing, leveling demand is tricky because our use of dishes varies widely from day to day depending on the complexity of meals we are making, the day of the week it is, how often we are eating out, etc. In general, we use somewhat less than a full load of dishes every day.
So I’ve simply chosen to streamline things as much as I can (such as hand-washing a small number of sippy cups instead of washing them in the dishwasher), and run the dishwasher once a day whether it’s full or not. This creates a simple routine where the washer gets loaded before bedtime and unloaded before breakfast, and dirty dishes go right in the washer all day instead of piling up other places.
Leveling out the demand for the dishwasher in this way has eliminated some waste, but not all of it. Although our dishwasher can run a “light” cycle, this only changes the amount of time it is being run. (We’re leveling use more than we are truly leveling demand.) Perhaps a better solution for us would be one of the drawer-style washers, since they are configured to run for true half-loads. Unfortunately, we are not ready for a new washer just yet.
So far, a load a day works pretty well, and I’m hardly the first to have the idea. It’s yet another situation where lean production leads to counter-intuitive results (running the dishwasher more can be more efficient rather than less), which is one reason I find it so fascinating.