It's not that easy to think imo, that means this solo miner has lots of resources or maybe with huge probability with free electricity he got in his sleeve to operate which not all miners have, imagine this his first time getting the reward, so what's his means to pay in electricity before? If not he have some asic joined in some pool but I don't think can cover his electricity cost, but to think he can solo mine, either he has free electricity as said or super cheap cost electricity.
the winner had a USB hub with like a dozen USB miner dongles on it.
not what i would call a farm. more so just a hobby miner.
this is his so called "farm"
the electric usage would have been way under 500w so would cost him about $1 in electric a day for the chance of a over $200k reward. he was very lucky to get that reward. but it was not due to him having a massive farm..
with all blocks of all pools there is always one asic that solves the block. always.. his chance of solving another one is probably more then 400 years away. so it was pure luck he had the solution. and also luck that he chose to use a pool with suck a large reward which was specified to the solution giver instead of sharing it out amongst everyone