Pointed Out.pdf

Energy transitions have been key to human evolution, with the first transition from traditional biofuels to inanimate energy converters, and later to fossil fuels, which began in England in the 16th century and took hold in Europe and North America after 1800. The transition to fossil fuels has resulted in gradual relative decarbonization, but enormous growth in absolute CO2 emissions. The combustion of natural gas produces less CO2 per unit of energy than coal or wood, with rates of 60 kg CO2/GJ, 95 kg CO2/GJ, and 110 kg CO2/GJ, respectively. As the global energy transition progressed, coal consumption was overtaken by hydrocarbons, and primary electricity generated by hydro power further reduced the average carbon intensity of the world's primary energy supply. However, absolute CO2 emissions have continued to grow, with combustion of fossil fuels contributing 8 million tonnes of carbon in 1800, 534 million tonnes in 1900, 6.77 billion tonnes in 2000, and 9.14 billion tonnes in 2018. The rising concentrations of CO2 have led to a gradual increase in average tropospheric temperature, with a rise of about 0.8C so far. The goal of decarbonization is to limit global warming, but despite concerns and agreements since the 1990s, the world has continued to rely on fossil fuels, with global emissions of CO2 increasing by over 60% since 1992. Historians of energy transitions are not surprised by this development, as previous transitions have shown that dominant sources of primary energy cannot be displaced rapidly, and the unfolding energy transition towards decarbonization will inevitably be a gradual and prolonged affair.