Fuel Switches: When Countries' Biggest Power Source Changed
51 of 109 countries generating at least 10 TWh have changed their largest source of electricity at least once since the Ember series began (1985 to 2025), and 58 have not. The most common switch was other fossil to gas, 20 times, followed by coal to gas (12). In each country's latest year (2025 for 82 of the 109) gas was the largest source in 41 of them. Wind or solar took the lead in 3 switches, in Denmark, Germany and Uruguay.
Key Facts, Ember data 1985 to 2025
- 109 countries were scored: each generated at least 10 TWh in its latest Ember year and has at least 10 years of data (series from 1985, newest year 2025).
- 106 confirmed switches of the largest source happened in 51 countries; 58 countries kept the same largest source throughout their series.
- A new leader counts only after leading for 2 consecutive years, so a single year in front is ignored; 27 of the 106 switches were close (under 2 percentage points of generation ahead in a confirming year).
- The most frequent switch was other fossil to gas: 20 switches in 15 countries (1988 to 2023, median year 2006).
- Switches to a low carbon leader numbered 29, switches away from one 23, between fossil categories 46 and between low carbon categories 8.
- Confirmed switches by decade: 1980s 4 (22 countries with data), 1990s 19 (45 countries with data), 2000s 34 (109 countries with data), 2010s 33 (109 countries with data), 2020s (to 2025) 16 (109 countries with data); earlier decades see fewer countries because many series start in 2000.
- gas 41, hydro 35, coal 17, nuclear 9, other fossil 3, wind 3, other renewables 1: the number of scored countries led by each source in each country's latest year (2025 for 82 of 109).
- Since 2016, 29 switches were confirmed; 14 to gas, 5 to coal, 5 to hydro.
- 38 switches reversed the one before (for example gas back to coal), which shows how close some grids sit between two sources.
- 3 countries had a new leader in its latest year that has not yet led for 2 years, so no switch is counted: Chile (solar, 2025), Pakistan (hydro, 2025) and Spain (solar, 2025).
- 106 of the 215 countries in the export were not scored: 106 generate under 10 TWh, 0 have fewer than 10 years of data.
Which Switches Happened Most Often
106 switches, 51 countries| Switch | Times | First | Median | Last | Countries |
|---|---|---|---|---|---|
| Other fossil to gas | 20 | 1988 | 2006 | 2023 | Azerbaijan, Dominican Republic, Egypt, Iran, Iraq, Italy, Jordan, Kuwait and 7 more |
| Coal to gas | 12 | 1999 | 2012 | 2024 | Greece, Hong Kong, Ireland, Israel, Japan, Philippines, Portugal, Spain and 3 more |
| Hydro to gas | 8 | 1988 | 2004 | 2022 | Argentina, Bolivia, Ghana, Myanmar, Portugal, Turkey, Vietnam |
| Coal to hydro | 7 | 1989 | 2003 | 2023 | Chile, Portugal, Romania, Sri Lanka, Vietnam, Zimbabwe |
| Coal to nuclear | 7 | 1986 | 2000 | 2023 | Bulgaria, Czechia, Slovenia, South Korea, Ukraine |
| Gas to coal | 7 | 1990 | 2012 | 2022 | Dominican Republic, Germany, Malaysia, Philippines, Romania, Turkey, United Kingdom |
| Gas to other fossil | 6 | 1992 | 2009 | 2018 | Iraq, Jordan, Pakistan, Saudi Arabia, Syria |
| Hydro to coal | 6 | 1999 | 2014 | 2023 | Cambodia, Chile, Portugal, Romania, Sri Lanka, Vietnam |
| Nuclear to coal | 6 | 1992 | 1999 | 2007 | Bulgaria, Japan, Slovenia, South Korea, Taiwan |
| Gas to hydro | 5 | 1993 | 2011 | 2024 | Argentina, Myanmar, Portugal, Vietnam |
| Other fossil to hydro | 5 | 2001 | 2010 | 2013 | Cambodia, Guatemala, Kenya, Sri Lanka, Sudan |
| Hydro to nuclear | 3 | 1994 | 2002 | 2013 | Sweden |
The 12 most frequent of 21 kinds of switch. Other fossil is Ember's category for oil and the other fossil fuels outside coal and gas, so other fossil to gas is mostly oil to gas. By direction: 29 switches went to a low carbon source (nuclear, hydro, wind, solar, bioenergy, other renewables), 23 went away from one, 46 were between fossil categories and 8 between low carbon ones. 38 switches reversed the one before in the same country.
When the Switches Happened
By decade, through 2025| Decade | Switches | Countries with data |
|---|---|---|
| 1980s | 4 | 22 |
| 1990s | 19 | 45 |
| 2000s | 34 | 109 |
| 2010s | 33 | 109 |
| 2020s (to 2025) | 16 | 109 |
Many series start in 2000, so earlier decades see fewer countries and fewer switches simply because fewer can be observed.
Ember annual statistics, 2000 to 2024, 108 countries
| Year | Gas | Hydro | Coal | Nuclear | Other fossil | Wind | Other renewables |
|---|---|---|---|---|---|---|---|
| 2000 | 24 | 34 | 24 | 8 | 18 | 0 | 0 |
| 2001 | 26 | 34 | 24 | 8 | 16 | 0 | 0 |
| 2002 | 28 | 33 | 24 | 9 | 14 | 0 | 0 |
| 2003 | 30 | 34 | 25 | 7 | 12 | 0 | 0 |
| 2004 | 32 | 33 | 25 | 7 | 11 | 0 | 0 |
| 2005 | 32 | 34 | 23 | 8 | 11 | 0 | 0 |
| 2006 | 33 | 34 | 22 | 8 | 11 | 0 | 0 |
| 2007 | 35 | 34 | 22 | 6 | 11 | 0 | 0 |
| 2008 | 34 | 35 | 22 | 5 | 12 | 0 | 0 |
| 2009 | 34 | 35 | 21 | 6 | 12 | 0 | 0 |
| 2010 | 33 | 36 | 22 | 6 | 11 | 0 | 0 |
| 2011 | 32 | 37 | 22 | 6 | 11 | 0 | 0 |
| 2012 | 31 | 36 | 24 | 6 | 11 | 0 | 0 |
| 2013 | 30 | 38 | 24 | 7 | 9 | 0 | 0 |
| 2014 | 31 | 38 | 22 | 8 | 8 | 1 | 0 |
| 2015 | 32 | 36 | 22 | 8 | 8 | 1 | 1 |
| 2016 | 35 | 36 | 22 | 8 | 5 | 1 | 1 |
| 2017 | 37 | 35 | 22 | 7 | 5 | 1 | 1 |
| 2018 | 36 | 36 | 22 | 7 | 5 | 1 | 1 |
| 2019 | 37 | 35 | 22 | 7 | 5 | 1 | 1 |
| 2020 | 40 | 35 | 21 | 6 | 4 | 1 | 1 |
| 2021 | 40 | 36 | 20 | 6 | 4 | 1 | 1 |
| 2022 | 40 | 35 | 21 | 6 | 4 | 1 | 1 |
| 2023 | 41 | 34 | 18 | 8 | 3 | 3 | 1 |
| 2024 | 41 | 35 | 17 | 8 | 3 | 3 | 1 |
The most recent switches
- 2024: Portugal went from gas to hydro.
- 2024: Taiwan went from coal to gas.
- 2023: Bulgaria went from coal to nuclear.
- 2023: Cambodia went from hydro to coal.
- 2023: Chile went from coal to hydro.
- 2023: Czechia went from coal to nuclear, a close call.
- 2023: Germany went from coal to wind.
- 2023: Syria went from other fossil to gas.
- 2023: Uruguay went from hydro to wind.
- 2022: Dominican Republic went from gas to coal, a close call.
- 2022: Myanmar went from hydro to gas.
- 2021: Sri Lanka went from coal to hydro.
Not counted yet: Chile (solar led in 2025), Pakistan (hydro led in 2025), Spain (solar led in 2025). A new leader needs 2 consecutive years in front, and the latest year is only the first.
Every Country
109 countries, biggest grid first| Country | Largest source | In the lead since | Switches | Latest switch | Lead now | All switches |
|---|---|---|---|---|---|---|
| ๐จ๐ณ China | Coal | 1985 or earlier | 0 | None | 41.5 points | None since 1985 |
| ๐บ๐ธ United States | Gas | 2016 | 1 | 2016: coal to gas | 22.6 points | 2016 coal to gas |
| ๐ฎ๐ณ India | Coal | 1985 or earlier | 0 | None | 61.5 points | None since 1985 |
| ๐ท๐บ Russia | Gas | 1985 or earlier | 0 | None | 27.3 points | None since 1985 |
| ๐ฏ๐ต Japan | Gas | 2009 | 3 | 2009: coal to gas(close) | 0.9 points | 1995 other fossil to nuclear; 2003 nuclear to coal (close); 2009 coal to gas (close) |
| ๐ง๐ท Brazil | Hydro | 1985 or earlier | 0 | None | 36.9 points | None since 1985 |
| ๐จ๐ฆ Canada | Hydro | 1985 or earlier | 0 | None | 33.1 points | None since 1985 |
| ๐ฐ๐ท South Korea | Coal | 1994 | 2 | 1994: nuclear to coal | 1.7 points | 1986 coal to nuclear; 1994 nuclear to coal |
| ๐ซ๐ท France | Nuclear | 1990 or earlier | 0 | None | 57.9 points | None since 1990 |
| ๐ฎ๐ฉ Indonesia | Coal | 2000 or earlier | 0 | None | 57.8 points | None since 2000 |
| ๐ฉ๐ช Germany | Wind | 2023 | 2 | 2023: coal to wind | 5.6 points | 1990 gas to coal; 2023 coal to wind |
| ๐ธ๐ฆ Saudi Arabia | Gas | 2016 | 4 | 2016: other fossil to gas | 31.6 points | 1992 gas to other fossil; 2001 other fossil to gas; 2008 gas to other fossil (close); 2016 other fossil to gas |
| ๐ฎ๐ท Iran | Gas | 1988 | 1 | 1988: other fossil to gas | 52.0 points | 1988 other fossil to gas |
| ๐ฒ๐ฝ Mexico | Gas | 2003 | 1 | 2003: other fossil to gas(close) | 62.5 points | 2003 other fossil to gas (close) |
| ๐น๐ท Turkey | Coal | 2018 | 2 | 2018: gas to coal | 12.2 points | 2000 hydro to gas; 2018 gas to coal |
| ๐ป๐ณ Vietnam | Coal | 2015 | 4 | 2015: hydro to coal(close) | 16.8 points | 1989 coal to hydro; 2004 hydro to gas; 2011 gas to hydro (close); 2015 hydro to coal (close) |
| ๐ฌ๐ง United Kingdom | Gas | 2014 | 3 | 2014: coal to gas(close) | 1.9 points | 1999 coal to gas; 2012 gas to coal; 2014 coal to gas (close) |
| ๐น๐ผ Taiwan | Gas | 2024 | 2 | 2024: coal to gas | 12.7 points | 1992 nuclear to coal; 2024 coal to gas |
| ๐ช๐ธ Spain | Gas(solar led in 2025) | 2017 | 3 | 2017: nuclear to gas(close) | -0.3 points | 2006 coal to gas; 2014 gas to nuclear (close); 2017 nuclear to gas (close) |
| ๐ฆ๐บ Australia | Coal | 1985 or earlier | 0 | None | 22.5 points | None since 1985 |
| ๐ฎ๐น Italy | Gas | 2000 | 1 | 2000: other fossil to gas | 30.5 points | 2000 other fossil to gas |
| ๐ฟ๐ฆ South Africa | Coal | 2000 or earlier | 0 | None | 73.3 points | None since 2000 |
| ๐ช๐ฌ Egypt | Gas | 1990 | 1 | 1990: other fossil to gas | 66.2 points | 1990 other fossil to gas |
| ๐ฒ๐พ Malaysia | Coal | 2016 | 2 | 2016: gas to coal | 11.4 points | 1992 other fossil to gas; 2016 gas to coal |
| ๐น๐ญ Thailand | Gas | 1985 or earlier | 0 | None | 44.8 points | None since 1985 |
| ๐ฆ๐ช United Arab Emirates | Gas | 1985 or earlier | 0 | None | 46.9 points | None since 1985 |
| ๐ต๐ฑ Poland | Coal | 1990 or earlier | 0 | None | 36.2 points | None since 1990 |
| ๐ต๐ฐ Pakistan | Gas(hydro led in 2025) | 2016 | 3 | 2016: other fossil to gas(close) | -0.1 points | 2002 other fossil to gas; 2008 gas to other fossil; 2016 other fossil to gas (close) |
| ๐ธ๐ช Sweden | Hydro | 2020 | 6 | 2020: nuclear to hydro | 12.7 points | 1994 hydro to nuclear (close); 2000 nuclear to hydro; 2002 hydro to nuclear (close); 2008 nuclear to hydro; 2013 hydro to nuclear (close); 2020 nuclear to hydro |
| ๐ณ๐ด Norway | Hydro | 1990 or earlier | 0 | None | 81.6 points | None since 1990 |
| ๐ฆ๐ท Argentina | Gas | 1996 | 3 | 1996: hydro to gas | 39.7 points | 1988 hydro to gas; 1993 gas to hydro; 1996 hydro to gas |
| ๐ฎ๐ถ Iraq | Gas | 2018 | 3 | 2018: other fossil to gas | 7.5 points | 2008 other fossil to gas; 2010 gas to other fossil; 2018 other fossil to gas |
| ๐ณ๐ฑ Netherlands | Gas | 1990 or earlier | 0 | None | 9.9 points | None since 1990 |
| ๐ฐ๐ฟ Kazakhstan | Coal | 1985 or earlier | 0 | None | 31.2 points | None since 1985 |
| ๐ต๐ญ Philippines | Coal | 2010 | 2 | 2010: gas to coal | 41.4 points | 2005 coal to gas (close); 2010 gas to coal |
| ๐บ๐ฆ Ukraine | Nuclear | 1996 | 1 | 1996: coal to nuclear | 34.8 points | 1996 coal to nuclear |
| ๐ง๐ฉ Bangladesh | Gas | 2000 or earlier | 0 | None | 42.8 points | None since 2000 |
| ๐ฉ๐ฟ Algeria | Gas | 2000 or earlier | 0 | None | 97.6 points | None since 2000 |
| ๐จ๐ด Colombia | Hydro | 2000 or earlier | 0 | None | 56.0 points | None since 2000 |
| ๐ฐ๐ผ Kuwait | Gas | 2014 | 1 | 2014: other fossil to gas | 26.9 points | 2014 other fossil to gas |
| ๐จ๐ฑ Chile | Hydro(solar led in 2025) | 2023 | 2 | 2023: coal to hydro | -2.8 points | 2012 hydro to coal; 2023 coal to hydro |
| ๐บ๐ฟ Uzbekistan | Gas | 2000 or earlier | 0 | None | 64.8 points | None since 2000 |
| ๐ซ๐ฎ Finland | Nuclear | 1990 or earlier | 0 | None | 12.3 points | None since 1990 |
| ๐ฎ๐ฑ Israel | Gas | 2015 | 1 | 2015: coal to gas | 63.5 points | 2015 coal to gas |
| ๐ป๐ช Venezuela | Hydro | 2000 or earlier | 0 | None | 86.6 points | None since 2000 |
| ๐จ๐ฟ Czechia | Nuclear | 2023 | 1 | 2023: coal to nuclear(close) | 7.1 points | 2023 coal to nuclear (close) |
| ๐ฆ๐น Austria | Hydro | 1990 or earlier | 0 | None | 37.8 points | None since 1990 |
| ๐ง๐ช Belgium | Nuclear | 1990 or earlier | 0 | None | 12.7 points | None since 1990 |
| ๐จ๐ญ Switzerland | Hydro | 2000 or earlier | 0 | None | 22.4 points | None since 2000 |
| ๐ต๐ช Peru | Hydro | 2000 or earlier | 0 | None | 19.9 points | None since 2000 |
| ๐ธ๐ฌ Singapore | Gas | 2002 | 1 | 2002: other fossil to gas | 88.4 points | 2002 other fossil to gas |
| ๐ฌ๐ท Greece | Gas | 2019 | 1 | 2019: coal to gas | 19.4 points | 2019 coal to gas |
| ๐ถ๐ฆ Qatar | Gas | 2000 or earlier | 0 | None | 92.3 points | None since 2000 |
| ๐ด๐ฒ Oman | Gas | 2000 or earlier | 0 | None | 86.5 points | None since 2000 |
| ๐ฑ๐ฆ Laos | Hydro | 2000 or earlier | 0 | None | 53.2 points | None since 2000 |
| ๐ต๐น Portugal | Hydro | 2024 | 7 | 2024: gas to hydro | 2.9 points | 1993 other fossil to coal; 1996 coal to hydro (close); 1999 hydro to coal; 2007 coal to gas (close); 2013 gas to hydro; 2017 hydro to gas; 2024 gas to hydro |
| ๐ท๐ด Romania | Hydro | 2018 | 4 | 2018: coal to hydro | 3.8 points | 1993 gas to coal (close); 1997 coal to hydro (close); 2000 hydro to coal; 2018 coal to hydro |
| ๐ง๐พ Belarus | Gas | 2000 or earlier | 0 | None | 18.8 points | None since 2000 |
| ๐ต๐พ Paraguay | Hydro | 2000 or earlier | 0 | None | 98.9 points | None since 2000 |
| ๐ฒ๐ฆ Morocco | Coal | 2000 or earlier | 0 | None | 47.2 points | None since 2000 |
| ๐ณ๐ฟ New Zealand | Hydro | 2000 or earlier | 0 | None | 31.8 points | None since 2000 |
| ๐ณ๐ฌ Nigeria | Gas | 2000 or earlier | 0 | None | 36.5 points | None since 2000 |
| ๐ญ๐บ Hungary | Nuclear | 2009 | 2 | 2009: gas to nuclear | 13.0 points | 2007 nuclear to gas (close); 2009 gas to nuclear |
| ๐ง๐ฌ Bulgaria | Nuclear | 2023 | 5 | 2023: coal to nuclear | 16.5 points | 2000 coal to nuclear (close); 2003 nuclear to coal; 2005 coal to nuclear (close); 2007 nuclear to coal; 2023 coal to nuclear |
| ๐ง๐ญ Bahrain | Gas | 2000 or earlier | 0 | None | 99.5 points | None since 2000 |
| ๐ญ๐ฐ Hong Kong | Gas | 2020 | 1 | 2020: coal to gas | 30.4 points | 2020 coal to gas |
| ๐ช๐จ Ecuador | Hydro | 2000 or earlier | 0 | None | 60.0 points | None since 2000 |
| ๐ท๐ธ Serbia | Coal | 1990 or earlier | 0 | None | 43.2 points | None since 1990 |
| ๐ฉ๐ฐ Denmark | Wind | 2014 | 1 | 2014: coal to wind | 35.5 points | 2014 coal to wind |
| ๐ฑ๐พ Libya | Gas | 2011 | 1 | 2011: other fossil to gas | 49.1 points | 2011 other fossil to gas |
| ๐ช๐น Ethiopia | Hydro | 2000 or earlier | 0 | None | 93.2 points | None since 2000 |
| ๐น๐ฒ Turkmenistan | Gas | 2000 or earlier | 0 | None | 99.9 points | None since 2000 |
| ๐ฎ๐ช Ireland | Gas | 2000 | 1 | 2000: coal to gas | 10.2 points | 2000 coal to gas |
| ๐ธ๐ฐ Slovakia | Nuclear | 1990 or earlier | 0 | None | 55.1 points | None since 1990 |
| ๐ฆ๐ฟ Azerbaijan | Gas | 2001 | 1 | 2001: other fossil to gas | 78.5 points | 2001 other fossil to gas |
| ๐ฐ๐ต North Korea | Hydro | 2000 or earlier | 0 | None | 28.7 points | None since 2000 |
| ๐ธ๐พ Syria | Gas | 2023 | 3 | 2023: other fossil to gas | 8.0 points | 2010 other fossil to gas; 2018 gas to other fossil; 2023 other fossil to gas |
| ๐ฌ๐ญ Ghana | Gas | 2020 | 1 | 2020: hydro to gas | 26.0 points | 2020 hydro to gas |
| ๐น๐ฏ Tajikistan | Hydro | 2000 or earlier | 0 | None | 89.8 points | None since 2000 |
| ๐ฏ๐ด Jordan | Gas | 2016 | 3 | 2016: other fossil to gas | 45.4 points | 2004 other fossil to gas (close); 2011 gas to other fossil; 2016 other fossil to gas |
| ๐ฉ๐ด Dominican Republic | Coal | 2022 | 2 | 2022: gas to coal(close) | 2.3 points | 2020 other fossil to gas; 2022 gas to coal (close) |
| ๐น๐ณ Tunisia | Gas | 2000 or earlier | 0 | None | 92.2 points | None since 2000 |
| ๐ฒ๐ฒ Myanmar | Gas | 2022 | 2 | 2022: hydro to gas | 0.0 points | 2005 gas to hydro; 2022 hydro to gas |
| ๐ฒ๐ฟ Mozambique | Hydro | 2000 or earlier | 0 | None | 66.5 points | None since 2000 |
| ๐ฟ๐ฒ Zambia | Hydro | 2000 or earlier | 0 | None | 75.4 points | None since 2000 |
| ๐ต๐ท Puerto Rico | Other fossil | 2000 or earlier | 0 | None | 19.5 points | None since 2000 |
| ๐จ๐บ Cuba | Other fossil | 2000 or earlier | 0 | None | 68.7 points | None since 2000 |
| ๐ฑ๐ฐ Sri Lanka | Hydro | 2021 | 3 | 2021: coal to hydro | 12.6 points | 2013 other fossil to hydro (close); 2019 hydro to coal; 2021 coal to hydro |
| ๐ฎ๐ธ Iceland | Hydro | 2000 or earlier | 0 | None | 42.5 points | None since 2000 |
| ๐ฐ๐ญ Cambodia | Coal | 2023 | 2 | 2023: hydro to coal | 26.7 points | 2013 other fossil to hydro; 2023 hydro to coal |
| ๐จ๐ฉ Democratic Republic of the Congo | Hydro | 2000 or earlier | 0 | None | 68.4 points | None since 2000 |
| ๐ฌ๐น Guatemala | Hydro | 2003 | 1 | 2003: other fossil to hydro(close) | 17.7 points | 2003 other fossil to hydro (close) |
| ๐ฆ๐ด Angola | Hydro | 2000 or earlier | 0 | None | 53.2 points | None since 2000 |
| ๐ธ๐ฎ Slovenia | Nuclear | 1995 | 2 | 1995: coal to nuclear(close) | 11.9 points | 1992 nuclear to coal; 1995 coal to nuclear (close) |
| ๐ธ๐ฉ Sudan | Hydro | 2010 | 1 | 2010: other fossil to hydro | 57.5 points | 2010 other fossil to hydro |
| ๐ญ๐ท Croatia | Hydro | 1990 or earlier | 0 | None | 18.1 points | None since 1990 |
| ๐ง๐ฆ Bosnia and Herzegovina | Coal | 2000 or earlier | 0 | None | 19.4 points | None since 2000 |
| ๐ฐ๐ช Kenya | Other renewables | 2015 | 2 | 2015: hydro to other renewables | 25.0 points | 2001 other fossil to hydro; 2015 hydro to other renewables |
| ๐ง๐ด Bolivia | Gas | 2003 | 1 | 2003: hydro to gas | 34.5 points | 2003 hydro to gas |
| ๐ฌ๐ช Georgia | Hydro | 2000 or earlier | 0 | None | 58.4 points | None since 2000 |
| ๐ต๐ฆ Panama | Hydro | 2000 or earlier | 0 | None | 32.2 points | None since 2000 |
| ๐จ๐ท Costa Rica | Hydro | 2000 or earlier | 0 | None | 62.9 points | None since 2000 |
| ๐ฐ๐ฌ Kyrgyzstan | Hydro | 2000 or earlier | 0 | None | 87.8 points | None since 2000 |
| ๐ญ๐ณ Honduras | Other fossil | 2001 | 1 | 2001: hydro to other fossil | 13.6 points | 2001 hydro to other fossil |
| ๐บ๐พ Uruguay | Wind | 2023 | 1 | 2023: hydro to wind | 13.2 points | 2023 hydro to wind |
| ๐ณ๐ต Nepal | Hydro | 2000 or earlier | 0 | None | 97.8 points | None since 2000 |
| ๐ง๐น Bhutan | Hydro | 2000 or earlier | 0 | None | 100.0 points | None since 2000 |
| ๐จ๐ฎ Cote d'Ivoire | Gas | 2000 or earlier | 0 | None | 43.1 points | None since 2000 |
| ๐ฟ๐ผ Zimbabwe | Hydro | 2003 | 1 | 2003: coal to hydro | 12.7 points | 2003 coal to hydro |
Largest source and lead are for each country's latest year (the table's newest is 2025); lead now is the gap, in percentage points of generation, between the largest and the second largest category. "Or earlier" means the source has led since the country's series began. Countries generating under 10 TWh are not listed (106 of them), and neither are 0 with fewer than 10 years of data. Column headings sort the table.
How This Is Measured, and Caveats
- Source means one of Ember's fuel categories as this site stores them: coal, gas, other fossil, nuclear, hydro, wind, solar, bioenergy and other renewables. They are not merged. A country that splits its power between, say, onshore and offshore wind still has wind counted once, but one that splits it across hydro, wind and solar has three small categories that a single fossil fuel can beat.
- A year's leader is the category with the most TWh. Two categories with exactly the same TWh are a tie: nobody leads that year and the previous leader keeps its place.
- A new leader counts only after it has led for 2 consecutive years, and the switch is dated to the first of them. A single year in front, followed by the old leader returning, is treated as a blip, which is how a wet year does not make hydro "switch" with coal and then switch back. If the newest year is the first year a new category leads, the switch is listed as not counted yet.
- A switch is marked close when the new leader's lead over the old one was under 2 percentage points of generation in either of its two confirming years. 27 of 106 switches are close, so treat their exact year as approximate.
- The first year of a country's series gives its starting leader, which is not a switch. Series start between 1985 and 2000 (109 of 109 scored countries start in 2000 or earlier), so a switch before a series began cannot be seen.
- Who is scored: countries generating at least 10 TWh in their latest year (the floor the records pages use) with at least 10 years of data. 106 of the 215 countries in the export are left out, because a single plant can change the leader of a small grid.
- Shares and leaders are by electricity generated, not capacity, and not by imports: a country that imports a lot can have a "largest source" that is a minority of what its homes use. Annual data cannot show why a switch happened (new plants, closures, a dry year, a fuel price change or a revision to Ember's series).
- Each country is read through its own latest year, which is 2025 for 82 of 109.
Fuel Switches FAQ
Which countries have switched their main source of electricity?
51 of 109 countries generating at least 10 TWh changed their largest source at least once between 1985 and 2025. Portugal (2024, gas to hydro), Taiwan (2024, coal to gas), Bulgaria (2023, coal to nuclear), Cambodia (2023, hydro to coal) and Chile (2023, coal to hydro) are among the most recent.
What was the most common fuel switch?
Other fossil to gas, 20 times in 15 countries. Coal to gas came next with 12. Other fossil is Ember's category for oil and other fossil fuels outside coal and gas, so a switch from it to gas is mostly oil to gas.
How is the largest source decided?
By generation in TWh in each calendar year, using Ember's fuel categories as the site stores them. A new source must lead for 2 consecutive years before a switch is recorded, and an exact tie changes nothing. The switch is dated to the first year of the new lead.
Why are some countries missing?
106 countries generate under 10 TWh a year, where one plant can change the leader, and 0 have fewer than 10 years of data. They appear on their own country pages but not in this ranking.
Does a switch mean the old source disappeared?
No. It means the new source generated more TWh than any other in the year. The old source can remain very large, and in a close grid the lead can change back, which is why close switches are marked.
Source: Ember (ember-energy.org), licensed under CC BY 4.0. Data as of 2025. Annual statistics from Ember; each country read through its own latest year.
Related
Cite this page
APA 7
World Power Monitor. (2025). Fuel Switches: When Countries' Biggest Power Source Changed. https://worldpowermonitor.com/fuel-switches/
Plain text
World Power Monitor. Fuel Switches: When Countries' Biggest Power Source Changed. Data as of 2025. Data from Ember. https://worldpowermonitor.com/fuel-switches/
BibTeX
@misc{wpm_fuel_switches_2025,
title = {{Fuel Switches: When Countries' Biggest Power Source Changed}},
author = {{World Power Monitor}},
year = {2025},
note = {Data as of 2025. Data from Ember.},
url = {https://worldpowermonitor.com/fuel-switches/}
} Permalink: https://worldpowermonitor.com/fuel-switches/
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