85% of today’s global primary energy comes from fossil fuels.
Since all fossil fuels were formed from organic material – during a process that took millions of years – they count as non-renewable. This means that their availability is limited and that those resources, inevitably, will run out at one point in the future. This problematic is – and especially was in the past – often described with the “Peak Oil” thesis. Today, it is believed, though, that the era of fossil fuels will not end because we run out of them, but rather because they will be replaced by alternative sources. The three mostly named fossil fuels are the refined products of oil (especially petroleum and kerosene), natural gas (primarily methane – CH4), and coal.
Generally, over the last 20 year all primary energy sources (except nuclear energy) had an increase in demand. Comparing the world energy mix by percentage, though, shows that oil and coal (and nuclear) have lost some points against gas, wind & solar which had a quicker growth in the measured time period.
Now, what does this mean concretely in terms of consumed fossil fuel energy?
While the world’s oil consumption was 39,587 TWh in 1995, it increased to 47,113 TWh in 2005 and to 51,937 TWh in 2015. The latest numbers from 2018 are standing at 54,220 TWh, which is an increase of 37% within a the last quarter century.
The world’s coal consumption has risen even more sharply. In 1995, coal amounted for 25,856 TWh but in 2005 this number rose to 36,152 TWh. Ten years later, coal produced already 43,833 TWh and the latest figures (2018) indicate a total coal consumption of 43,870 TWh. For the last 25 years, coal accumulated consequently a 70%-growth over this period.
And gas, too, increased its volume over the last decades. From 21,109 TWh in 1995 to 27,445 TWh in 2005, and about 34,665 TWh in 2015. The latest numbers from 2018 find an annual gas consumption of 38,489 TWh. The gas industry, therefore, increased its available energy volume by 82% during the last quarter-century.