i don't mean to be argumentative but i haven't seen many pennies become corroded. also copper pipes in houses I've worked on have held up really well. I'm pretty sure a copper water line is more likely to oxidize via galvanic corrosion instead of moisture.
buttons on a controller seem to be at much lower risk of corrosion with respect to pennies, water lines, etc.
don't fuck with substations. you'll kill yourself and cause a power outage. this doesn't help us. it might also put lives in danger like those who are in hospitals.
but then it's re-enabled every time you have to sign in :p