UBC economist William Rees argues that we are -- in George Bush Sr.'s memorable phrase -- "in deep do do:"
We can probably agree that techno-industrial societies are utterly dependent on abundant cheap energy just to maintain themselves — and even more energy to grow. The simple fact is that 84 per cent of the world’s primary energy today is derived from fossil fuels.
It should be no surprise, then, that carbon dioxide from burning fossil fuels is the greatest metabolic waste by weight produced by industrial economies. Climate change is a waste management problem!
Cheap fossil energy enabled the world to urbanize, and this process is continuing. The UN expects the urban population to rise to 6.7 billion — 68 per cent of humanity — by 2050. There will be 43 mega-cities with more than 10 million inhabitants each as early as 2030, mostly in China and other Asian countries.
By 2018, the combustion of fossil fuel alone was pumping 37.1 billion tonnes of carbon dioxide into the atmosphere. Add to this the net carbon emissions from land clearing (soil oxidation) and more vigorous forest fires, and we can see why atmospheric carbon dioxide concentrations reached an all-time high of 415 parts per million in early 2019.* This is 48 per cent above pre-industrial levels and concentrations are rising exponentially.
We'd like to think that green energy will save the day. But Rees claims that's a pipe dream:
There is plenty of superficial support for the notion that green tech is our saviour. We are told repeatedly that the costs of providing renewable energy have fallen so low that it will soon be practically free. Australian professors Andrew Blakers and Matthew Stocks say “Solar photovoltaic and wind power are rapidly getting cheaper and more abundant — so much so that they are on track to entirely supplant fossil fuels worldwide within two decades.” Luckily, the transition won’t even take up much space: UC Berkeley professor Mehran Moalem argues that “an area of the Earth 335 kilometres by 335 kilometres with solar panels... will provide more than 17.4 TW power.... That means 1.2 per cent of the Sahara desert is sufficient to cover all of the energy needs of the world in solar energy.” (Someone should remind Prof. Moalem that, even if such an engineering feat were possible, a single sandstorm would bury the world’s entire energy supply.)
The growth in demand exceeds additions to supply from renewables, the latter cannot displace fossil fuels even in electricity generation — and remember, electricity is still less than 20 per cent of total energy consumption, with the rest being supplied mostly by fossil fuels.
Nor is any green transition likely to be cheap. The cost of land is substantial and, while the price of solar panels and wind turbines have declined dramatically, this is independent of the high costs associated with transmission, grid stabilization and systems maintenance. Consistently reliable wind and solar electricity requires integrating these sources into the grid using battery or pumped hydro storage, back-up generation sources (e.g., gas turbines, cruise-ship scale internal combustion engines, etc.) and meeting other challenges that make it more expensive.
Also problematic is the fact that wind/solar energy is not really renewable. In practice, the life expectancy of a wind turbine may be less than 15 years. Solar panels may last a few years longer but with declining efficiency, so both turbines and panels have to be replaced regularly at great financial, energy and environmental cost. Consider that building a typical wind turbine requires 817 energy-intensive tonnes of steel, 2,270 tonnes of concrete and 41 tonnes of non-recyclable plastic. Solar power also requires large quantities of cement, steel and glass as well as various rare earth metals.
We are, Rees argues, like Sisyphus -- rolling that stone up the hill, only to see it roll down again.
These are not pleasant thoughts for a Sunday morning. But I offer them for your consideration.
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