If you sometimes use an electric
kettle to heat water
for drinks, then you might be interested in buying
an instant hot water
It uses half the power of a kettle and will make an instant 220ml coffee using only 16 wh (0.7ah at 24v)
for comparison a 2100w kettle needs about 2ah at 24v.
The one I have is a Bosch Filtrino 2023
easy heat settings up to a real 100 degrees
easy cup size fill adjustment
2l water capacity with the option to fit a brita filter cartridge
takes up slightly more space than an electric
1600w and uses so little power, your batteries wont notice it.