It’s plausible that handwashing uses less electricity, specially if you let the machine heat-dry the dishes. But water? If you do the comparison against a fully-loaded machine, no way. Modern machines use half the water from machines of 15 years ago, and those were already competitive against handwashing. Best case scenario for handwashing (single water bath) still uses about twice as much water. Dishwasher detergent is stronger and the machine takes longer so it has more contact time, the chemistry heavily favours using less water for the same amount of gunk to dissolve.
In your case, as you already mentioned you only cook once a day and you don’t want to degrade your high end stuff in the machine, it’s reasonable that you won’t generate dishes enough to fill the machine. If you would be using a half-loaded dishwasher then it is plausible that you would use less water handwashing, but it’s still a close call - which is why I sometimes use the machine filled 1/3 without worry.