What are the merits and demerits of 50 Hz and 60 Hz AC system? Which one is better?
Transformers need to be a little bigger for 50Hz because it is less efficient in lower frequency.
"In short, 50 Hz vs 60 Hz is more likely similar to Coca Cola vs Pepsi Cola."
Probably the relative merits of one vs the other are not enough to justify the cost of anyone changing, so they will stay different.
They will probably stay unchanged until a multi-voltage DC distribution system can be made to work efficiently.
That may not be too far in the future. There are not a vast number of loads that couldn't be run on DC - at least there wouldn't be if the appropriate technology was already available for the distribution system. Just think - multiphase induction motors with the speed controlled by the frequency of the supply. (That's not BS, is it?)
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