I've been playing ogame for almost 10 years now. On and off, always as a miner.
I had never used fusion before but decided to give it a go.
Currently, I'm using zero solar plants. zero satellites. Energy tech level 17 and fusion reactor lvl 18. It powers a 32/29/27 mine setup (I know, they're still low. I just got back)
Anyway, I've been doing some rough math and repairing satellites like 10 times or more is probably cheaper than running fusion on all planets, considering the fusion reactor cost and the energy tech cost.
BUT, isn't it worth it in the long run, just to not be worried in case a bored fleeter decides to bash you out of spite or in case of a war?
I mean, if your satellites are crashed, it will turn down your production until you repair them, and on top of that, you're not adding tons of crystal to a debris field, making it a less profitable target.
Let me know your thoughts.