I built a golden accumulator. in my assumption to buy power I got surprised that it sells power.
Does this mod have a feature to buy power too? If it has, how is it done?

use a transformer to pump power to or from the accumulator, it works so it never gets full or empty.
btw if you like this mod and don't want it to die, please support my request at https://forums.factorio.com/viewtopic.php?f=28&t=85372&p=497720#p497720

Hmm.
I don't see a transformer-item anywhere. Care to elaborate?

Hmm.
I noticed yesterday that it either buys or sells power automatically, depending on whether you lack power or have lots of power.
Or so I think.