I don’t refute your claim, but I think on average people are unable to match a dishwasher.
12 litres for 150 items is ridiculously good. The university of Bonn indicates that the equivalent handwash uses 100L, and in some cases 300-400L. Pre-rinsing uses 100L alone. These are averages. Some people are extremely good, others are terrible. In some countries it’s customary to let the tap run while washing dishes, etc, so that’s why the extremes vary so wildly.
I also think that sink setup has a massive impact. In my current flat (which came with a dishwasher) I only have a single sink. It’s complicated to be efficient with water, unless I use a secondary container where I can store soapy dishes together until I can rinse everything. Years ago when I lived in a flat without a dishwasher, it had “three sinks” (two large and deep ones, and a smaller area in the middle). It was trivial to have a little soapy water on one side, wash everything, move it to the other side, and literally rinse and repeat. Water usage was greatly reduced compared to my current setup.
The only thing I don’t run in the dishwasher are wooden items and the couple of non-stick items I still have left.
12 litres for 150 items is ridiculously good. The university of Bonn indicates that the equivalent handwash uses 100L, and in some cases 300-400L. Pre-rinsing uses 100L alone. These are averages. Some people are extremely good, others are terrible. In some countries it’s customary to let the tap run while washing dishes, etc, so that’s why the extremes vary so wildly.
I also think that sink setup has a massive impact. In my current flat (which came with a dishwasher) I only have a single sink. It’s complicated to be efficient with water, unless I use a secondary container where I can store soapy dishes together until I can rinse everything. Years ago when I lived in a flat without a dishwasher, it had “three sinks” (two large and deep ones, and a smaller area in the middle). It was trivial to have a little soapy water on one side, wash everything, move it to the other side, and literally rinse and repeat. Water usage was greatly reduced compared to my current setup.
The only thing I don’t run in the dishwasher are wooden items and the couple of non-stick items I still have left.