Energy Sources

Nine primary sources, side by side: nuclear, fossil and renewable. Covers: Nuclear Energy, Non-renewable Sources and Renewable Sources.

Nine ways to boil water, or to avoid boiling it at all

Almost all electricity on the planet is produced one of two ways: spinning a turbine with steam, water or air, or turning light directly into current. Behind that simple mechanical gesture sit mines, wells, dams, platforms, factories and reactors that are very different from one another, and each one distributes the environmental cost in a different way: some concentrate it in the air we breathe today, others in land that takes generations to recover, others in waste that has to be watched for centuries.

This route compares nine primary sources — nuclear fission, its waste and its safety, coal, oil and its derivatives, natural gas, biomass, wind, geothermal, hydropower and solar — always asking the same questions: what has to be extracted or built, what happens during operation, what is left afterward, and what happens to the person or ecosystem closest to the process?

Why the figures vary so much

The same number — grams of CO₂ per kilowatt-hour, deaths per terawatt-hour, liters of water per unit of energy — can triple between one study and another depending on which stage of the life cycle it includes, which electricity mix powers the factory or the mine, and which historical accident is counted or excluded. That is why every leaf in this section presents figures as sourced ranges, not a single final number, and the data tab explains where each range comes from and what it leaves out.

A question worth asking for every source

No primary source is free in material terms. The honest comparison is not "which one is clean?" but "which combination of these nine sources causes the least total damage — climate, land, health — for the electricity service we actually need, and for how long?". The answer changes with the country, the climate, the available grid and the historical moment; there is no fixed winning source, only a balance that has to be redone with up-to-date data.