mm wrote:

There are wall switches with a weekly timer. You can have it turn on
an outlet for 10 minutes a week.

You can also use standard mechanical timers. Have it turn on for one
hour every 24 hours and when it is on have it power another such timer
that will turn on for one hour of every 24 hours of elapsed time, and
run the charger off of that.

So the first timer will run all the time, and the second timer will
take 24 days to cover 24 hours. So the charger will be on one hour
every 24 days.


That sounds like a sensible (and cheap) solution.