Abundant and cheap but only generates when the sun shines — needs storage or backup to cover nights and cloudy days.

Wind is the fastest growing source of clean electricity globally — offshore wind in particular has seen dramatic cost reductions.

Electricity from rivers and dams. Largely determined by geography — Norway and Brazil generate most of their power this way.

Heat from the earth converted to electricity. Very limited in most countries but a major source in Kenya and Iceland.

Electricity from ocean tides and waves. Still early stage globally — potential varies significantly by coastline and geography.

Energy from organic material like wood pellets. Provides reliable power but its green credentials are debated — it still releases CO2 when burned.

Low carbon and reliable 24/7, but expensive to build and slow to deliver. France generates around 70% of its electricity from nuclear.