I have not come across any numbers predictiv this year's voter turnout, but I would guess it will be within the average of the last two decades (roughly 75-80 %). Fear of extremists (in Germany, understandably, first of all fear of rightist extremists), has been largely absent - no matter if high or low voter turnout. Which is, by the way, a success that has to be ascribed to the Left Party. (A topic I really want to elaborate on; maybe tomorrow)

is there something  like the GOTV in Germany?

Not like in, say, the US. Simply because there is not the necessity. In the US, you have weak party organisations and low voter turnout, so distinct GOTV actions and organisations become necessary. In Germany with its strong party organisations, GOTV happens along the line of party membership (party members bringing the family to the ballot box, making shuttle services for old people's homes etc). But it is not being called "get out the vote", and there is not a special word for it, at least as far as I know.