South Korea
KORNuclear overtook gas on South Korea's grid in 2022.
Today nuclear supplies 30% and gas 28%.
What this grid depends on
Three measures that say more about a country than how much power it makes. Open “what this means” on any of them if the term is new.
Cleaner than 5 in 10 grids worldwide.
What this means
How much planet-warming gas is released to make one unit of electricity. Two countries can generate exactly the same amount and one of them be ten times dirtier doing it. Lower is better.
South Korea generates almost exactly what it uses, with next to nothing crossing its borders.
What this means
Electricity can be sold across a border like anything else, through high-voltage lines connecting one country's grid to the next. Buying it in means leaning on a neighbour to keep the lights on. Selling it means generating more than the country needs.
Most of the fuel behind this grid is bought from abroad.
What this means
How much of what this grid runs on the country can supply itself. Sun, wind and water count fully, because nobody can cut them off; coal, gas and oil only as far as the country digs them up. A high score is not the same as a good grid: mining your own coal scores well, importing uranium scores badly.
Also true of South Korea
South Korea gets next to none of its electricity from hydro, in a region built on it.
41% of grids in Asia draw more than a tenth of their power from hydro.
South Korea's electricity is about as carbon-heavy as the world's.
417 grams of CO2e a kilowatt-hour, against a world figure of 458.
South Korea has no dominant fuel at all.
Its largest single source supplies just 31% of the grid.
South Korea’s neighbours
Figures are for 2025, the most recent year reported for South Korea. Generation shares are a percentage of electricity generated, not of energy used. How this is calculated.