Which countries run their grids at 50 Hz and which at 60 Hz, and what that means for a turbine, a generator or a whole plant that has to move between them.
Most of the Americas run at 60 Hz, along with a handful of countries elsewhere. The rest of the world runs at 50 Hz.
| Region | 60 Hz | 50 Hz |
|---|---|---|
| North America | United States, Canada, Mexico, Bermuda | Greenland |
| Central America | Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama | None |
| Caribbean | Antigua and Barbuda, Bahamas, Cuba, Dominican Republic, Haiti, Saint Kitts and Nevis, Trinidad and Tobago; and the territories of Anguilla, Aruba, the British Virgin Islands, the Cayman Islands, Montserrat, Puerto Rico, Sint Maarten and the US Virgin Islands | Barbados, Dominica, Grenada, Jamaica, Saint Lucia, Saint Vincent and the Grenadines; and Bonaire, Curaçao, Guadeloupe and Martinique |
| South America | Brazil, Colombia, Ecuador, Guyana, Peru, Suriname, Venezuela | Argentina, Bolivia, Chile, Paraguay, Uruguay, French Guiana |
| Europe | None | Every country |
| Africa | See the note on Liberia | Every other country |
| Middle East | Saudi Arabia | Every other country |
| Asia | South Korea, Taiwan, the Philippines, and western Japan | Every other country, including China, India and eastern Japan |
| Oceania and the Pacific | American Samoa, French Polynesia, Guam, Palau | Australia, New Zealand and most other island states |
Mains frequency as published in public tables of national standards, checked in October 2026. Liberia appears at 60 Hz in some tables and 50 Hz in others. An island or an industrial site can differ from its country, so confirm the frequency at the point of connection before specifying a machine.
A grid’s frequency is the speed of every generator on it. That is why it is the first line of a requirement and the first line of a data sheet.
A two-pole generator makes 50 Hz at 3,000 rpm and 60 Hz at 3,600 rpm. A turbine coupled straight to it is designed around that speed.
The GE 7EA and 7FA and the Siemens 501D5 and 501F are 60 Hz machines. The GE 9E and 9FA and the Siemens V94.2 are 50 Hz machines. None can be economically converted.
The GE Frame 5 and Frame 6B drive their generators through a gearbox, and the Alstom GT11N2 does for 50 Hz. The GE LM2500, TM2500 and LM6000 are offered for both grids. A unit is still built for one frequency, so the package has to match.
Generators, transformers and motors are built for one frequency as well. Moving a plant between grids means checking each of them, not only the turbine.
The gas turbine frames Genloop is asked about most, sorted by the grid they serve.
| Grid | Frames | Markets |
|---|---|---|
| 60 Hz only | GE 7EA, Siemens 501D5, Siemens 501F, GE 7FA | North and Central America, Brazil and the north and west of South America, Saudi Arabia, South Korea, Taiwan, the Philippines, western Japan |
| 50 Hz only | GE 9E, Siemens V94.2, GE 9FA | Europe, Africa, most of Asia and the Middle East, Australia, and Argentina, Bolivia, Chile, Paraguay and Uruguay |
| Either grid | GE Frame 5, GE Frame 6B, Alstom GT11N2, GE LM2500 and TM2500, GE LM6000 | Anywhere, once the package matches the grid |
Each frame’s output and speed are in the frame comparison. Genloop’s 50 Hz holdings are on one page, and the register gives the frequency of every unit.
Short answers, for a first conversation about a unit that has to cross a border.
The United States, Canada, Mexico, all of Central America and much of the Caribbean. In South America: Brazil, Colombia, Ecuador, Guyana, Peru, Suriname and Venezuela. Outside the Americas: Saudi Arabia, South Korea, Taiwan, the Philippines and western Japan.
Almost everywhere else: all of Europe, nearly all of Africa, the Middle East apart from Saudi Arabia, most of Asia including China and India, Australia and New Zealand, and in South America Argentina, Bolivia, Chile, Paraguay and Uruguay.
Both. Eastern Japan, including Tokyo, Yokohama, Sendai and Sapporo, runs at 50 Hz. Western Japan, including Osaka, Kyoto, Nagoya and Hiroshima, runs at 60 Hz. Frequency converter stations join the two halves.
Not a direct-drive heavy frame. Its compressor and turbine are designed for 3,600 rpm, and a 50 Hz generator needs 3,000 rpm. A geared frame such as the GE 6B can be converted, because the change is made at the gearbox, and aeroderivative packages are built for either grid. For a 50 Hz project the practical answer is a machine built for 50 Hz.
It decides where a machine can go. A direct-drive 60 Hz frame can only be placed in a 60 Hz country, and the same holds at 50 Hz. Frequency is the first thing a buyer checks, and one of the first things that sets the market for a used unit.