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Archive for Abril, 2019

One of the great misconceptions of our time is the belief that we can move away from fossil fuels if we make suitable choices on fuels. In one view, we can make the transition to a low-energy economy powered by wind, water, and solar. In other versions, we might include some other energy sources, such as biofuels or nuclear, but the story is not very different.

The problem is the same regardless of what lower bound a person chooses: our economy is way too dependent on consuming an amount of energy that grows with each added human participant in the economy. This added energy is necessary because each person needs food, transportation, housing, and clothing, all of which are dependent upon energy consumption. The economy operates under the laws of physics, and history shows disturbing outcomes if energy consumption per capita declines.

There are a number of issues:

  • The impact of alternative energy sources is smaller than commonly believed.
  • When countries have reduced their energy consumption per capita by significant amounts, the results have been very unsatisfactory.
  • Energy consumption plays a bigger role in our lives than most of us imagine.
  • It seems likely that fossil fuels will leave us before we can leave them.
  • The timing of when fossil fuels will leave us seems to depend on when central banks lose their ability to stimulate the economy through lower interest rates.
  • If fossil fuels leave us, the result could be the collapse of financial systems and governments.

[1] Wind, water and solar provide only a small share of energy consumption today; any transition to the use of renewables alone would have huge repercussions.

 

According to BP 2018 Statistical Review of World Energy data, wind, water and solar only accounted for 9.4% 0f total energy consumption in 2017.

Figure 1. Wind, Water and Solar as a percentage of total energy consumption, based on BP 2018 Statistical Review of World Energy.

Even if we make the assumption that these types of energy consumption will continue to achieve the same percentage increases as they have achieved in the last 10 years, it will still take 20 more years for wind, water, and solar to reach 20% of total energy consumption.

Thus, even in 20 years, the world would need to reduce energy consumption by 80% in order to operate the economy on wind, water and solar alone. To get down to today’s level of energy production provided by wind, water and solar, we would need to reduce energy consumption by 90%.

[2] Venezuela’s example (Figure 1, above) illustrates that even if a country has an above average contribution of renewables, plus significant oil reserves, it can still have major problems.

One point people miss is that having a large share of renewables doesn’t necessarily mean that the lights will stay on. A major issue is the need for long distance transmission lines to transport the renewable electricity from where it is generated to where it is to be used. These lines must constantly be maintained. Maintenance of electrical transmission lines has been an issue in both Venezuela’s electrical outages and in California’s recent fires attributed to the utility PG&E.

There is also the issue of variability of wind, water and solar energy. (Note the year-to-year variability indicated in the Venezuela line in Figure 1.) A country cannot really depend on its full amount of wind, water, and solar unless it has a truly huge amount of electrical storage: enough to last from season-to-season and year-to-year. Alternatively, an extraordinarily large quantity of long-distance transmission lines, plus the ability to maintain these lines for the long term, would seem to be required.

(mais…)

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Jay Hanson ( ? – 2019)

Dieoff

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