I cofounded the Hackerfleet[1] Community, a (rather too small, join! :) group of sailing hackers and nerds.
Since we operate our tech stacks with batteries and often only solar/wind power, we try to come up with very energy conservative solutions.
One thing we couldn't do without: ARM CPUs even for servers, because they're quite energy efficient.
If you have any questions, i'll be checking this comment thread for a few days.