1) Heating engineer to show surprise with power cut? A lot getting cut off (6) G?S?A? All I can think of is GASMAN, which I suppose could be a heating engineer, but I can't make any sense of the rest of the clue.
2) Electric current introduced to harbour crane? (5) H?I?T The definition would seem to be crane (HOIST), and I = electric current inside "harbour". But how/why does harbour = host?