Dr Smil. Photo by: Olibroman at English Wikipedia, CC BY-SA 3.0
Dr. Smil, who modestly refers to himself as “just an old-fashioned” scientist, is Distinguished Professor Emeritus in the University of Manitoba’s Department of Environment and Geography. We thank him for letting us draw from his paper: Examining Energy Transitions: A Dozen Insights Based on Performance (University of Manitoba. 2016.).
We’ll pick up at point 4 for this week’s blog post, doing our best to present Dr. Smil’s work in lay terms.
Why shift primary energy sources?
- According to Dr. Smil, the purpose behind the unfolding energy transition is to prevent an excessive rise in the earth’s average tropospheric temperature; only decarbonization of the global energy supply can achieve that.
- Carbon dioxide emitted from burning fossil fuels quickly spreads throughout the earth’s atmosphere. As a result, the earth’s temperature is affected by the combination of all global carbon dioxide emissions.
- Concentrations of carbon dioxide gas in the atmosphere have increased steadily since first measured in 1959.
- As such, the progress of energy transition must be measured on the global scale – even if individual countries draw most of their primary energy from non-carbon sources (such as hydro) or modern renewable sources (also known as new renewable sources, e.g., wind, photovoltaic or central solar power).
Reasons for the slow shift
- In recent decades, there is no evidence that the global transition of primary energy supply is accelerating. And, carbon intensity continues to be high for global commercial energy supply.
- In 1960, fossil fuels supplied 97 per cent of the world’s primary commercial energy; in 1990 their share was 90 per cent; and in 2015, it was about 85 per cent. When traditional biofuels are included, fossil fuels accounted for 80 per cent of total global primary energy in 2015.
- Carbon intensity of commercial energy supply (i.e., the number of grams of carbon dioxide emitted for every megajoule of energy produced) declined by an average of 28 per cent during the 20th century due to the rise in natural gas, hydro and nuclear electricity. However, with expanded coal extraction in Asia since the early 2000s, the carbon intensity rate had risen slightly by 2015.
- A shift in fuel for use in electricity generation has been the most significant aspect of the global energy transition so far. However, that shift only had a small effect on decarbonizing the overall primary energy supply.
- As was common in the early stages of past energy trends, there was rapid growth in new sources. Following this trend, global wind and solar electricity generation grew rapidly, averaging about 22 per cent and 37 per cent between 2000 and 2015, respectively.
- Despite that rapid growth, they contributed only about 1.3 per cent of the world’s primary commercial energy supply after 25 years of development (1990 to 2015). When modern biofuels are added, all modern renewables claimed about 2.5 per cent of energy supply in 2015.
- Global growth of modern renewables has not been especially rapid.
- Renewable global energy supply roughly doubled in 25 years, with an average annual growth rate of about three per cent, which is not unusually rapid for the early stages of energy transitions.
- In historical contrast, coal supply grew at a rate of more than five per cent per year between 1850 and 1870; oil gains averaged more than eight per cent per year during 1880 to 1900; and natural gas grew at six per cent per year between 1920 and 1940.
- Between 1990 and 2015, the world added 25 times as much energy supply from fossil fuels as it did in modern renewables.
- Progress has been gradual, even in the case of the most determined, deliberate and costly shift – Germany’s Energiewende.
- When Energiewende began in 2000, Germany drew 83.7 per cent of its primary energy from fossil fuels; in 2015 that share declined to 79.4 per cent. The average decline was merely 0.3 per cent per year, which, if that trend continues, would leave fossil fuels dominant in Germany even up to 2050.
In part 3 we’ll look at the final points of Dr. Smil’s paper, including:
- The reasons behind continued persistence of carbon in energy supply.
- The challenge of displacing liquid fossil fuels for transportation.
- Fossil fuels in the production of iron, cement, and plastics.