University of Manitoba professor Vaclav Smil is regarded as an international authority on the history of energy transitions. Science Magazine calls him “the man who has quietly shaped how the world thinks about energy.” In the words of Bill Gates “there is no author whose books I look forward to more than Vaclav Smil.”
Energy transitions have been among the key defining processes of human evolution. The first millennia-long transition was from the reliance on traditional biofuels such as wood, charcoal, crop residues and animate sources of energy derived from human and animal muscles, to increasingly common reliance on inanimate energy converters. They included water wheels, wind mills and better harnessed draft animals for fieldwork and transportation.
Transition to fossil fuels to produce heat, thermal electricity and kinetic energy began in England during the 16th century. It took hold in Europe and North America only after 1800, and in most of Asia only after 1950.
This transition has been accompanied by increasing reliance on primary electricity, dominated by hydroelectricity since the 1880s, with nuclear generation contributing since the late 1950s. The transition from traditional biofuels to fossil fuels has resulted in gradual relative decarbonization, but also in enormous growth in absolute emissions of CO2.
This decarbonization that has resulted due to the move away from traditional biofuels to hydroelectricity and fossil fuels that dominate today is best traced by the increasing hydrogen-to-carbon ratios of major fuels.
They rise from no more than 0.5 for wood and 1.0 for coal, to 1.8 for the lightest refined fuels and to 4.0 for methane, the dominant constituent of natural gas. The reverse order applies to CO2 emissions per unit of energy.
For the rest of this policy paper: https://www.schoolofpublicpolicy.sk.ca/research/publications/policy-brief/what-we-need-to-know-about-the-pace-of-decarbonization.php