Electrical supply

Early in the history or electricity, Nikola Tesla devised a system of three-phase AC electricity combining voltage from those phases. He had calculated that 60Hz was the most effective frequency for that combination. With the backing of the Westinghouse Company, Tesla's AC system became the
standard in the United States.

The German company AEG started generating electricity and became a virtual monopoly in Europe. They decided to use 50Hz instead of 60Hz to better fit their metric standards.

Today, in Asia, the frequency of electricity depends to some extent on history. India was ruled by the British, so the frequency is 50Hz , while the Philippines was ruled by the United States, so the frequency of electrical devices is 60Hz.

Transformer losses, generator inefficiencies, motor inefficiencies, and distribution losses are higher at 50Hz. However once a country has an infrastructure and its inhabitants have their appliances no one is going to change frequencies.