how about a delayed start (in my country electricity is cheaper at night)? You could add "half full" function, cutting wash times when the dishwasher is not fully filled in or filled with relatively easy to clean stuff.
Also, do you have alternative hot water source, like solar panels? That would be a great saver if you would use "free" hot water instead of heating it.
My dishwasher analyses the transparency of disposed water to judge if it is clean enough.
Am I adding too much "feature creep? ]
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