Means a meter that records input as well as output and no, Germany so far does not have anything in place where regular folk get paid for what they input.

But as I said, everything I generate goes directly into my own consumption, so I don't mind much.

Basically that. As long as he's using 100% himself it doesn't really matter, but a friend of mine has one of those old Ferraris meters and getting full price for every kWh fed to the grid means, the whole thing pays for itself within two years.