Fossil fuels are non-renewable, polluting energy sources that we burn daily to power the world. GHG emissions and toxic compounds are released into the environment as a result, contributing to both global warming and pollution. Cities are no strangers to such pollution, as there are over 1 billion cars on the road that burn fossil fuels every day and decrease urban air quality. Biodiversity is also affected by the air, water, and soil pollution caused by fossil fuel consumption. It’s extremely important that we prevent such contamination, since what harms the environment directly threatens humans.
Fossil fuels are dominating the global energy and electricity mixes – and it seems as though that will remain the case in the near future. Although a few local electricity mixes are practically fossil-fuel-free, they usually aren’t examples that the rest of the world can follow. Additionally, electricity only represents around a fifth of energy consumption worldwide, so we can’t just focus on electricity mixes if we intend on significantly reducing our emissions.
Different sources of energy are used by the different sectors of our societies. We’ll see that in detail in later sections.