The World Energy Scene – Some Basic Math


I believe everyone should have a decent level of familiarity with this Wikipedia listing on the world energy scene, which provides a bit of top-level math. As a civilization, we consume energy at the rate of 15 terawatts (15,000,000,000,000,000)– an estimated 80% – 90% of which comes from fossil fuels. Thus, when we talk about a gigawatt solution — certainly nothing to sneeze at — we’re talking about something that provides 1/15,000th of the world’s energy.

Or, as I was explaining to my daughter just now, the total energy being consumed in the world is about 150 billion times the lighting in my office (about 100 watts). She was utterly fascinated. Yeah right — a bit of holiday humor for you there.

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  1. To continue your numbers further: that 15 terawatts could be produced by a 5% efficient PV solar cell the size of Oregon. It doesn’t have to be a single big panel, it could be spread out all over the planet, even over the ocean. So is making something the size of Oregon impossible? Consider that we cultivate crop land 60 times the area of Oregon today on earth. BTW, solar PV isn’t the only way to get clean energy – wind, hydro, geothermal, tidal, also work.

    • Clean energy that has to rely on the continued use of fossil fuels to back them up when sun is down or wind ain’t blowing is not ‘clean’ and those calling them ‘clean’ are mistaken and misled by political ideology that is false in terms of realities of ecology and climate. The initial production and disposal at end of life of these technologies are also no cleaner than any other energy source. And why scar our lands with these inefficient energy sources when you can have nuclear power plants using a fraction of the footprint, that run for long periods of time without needing to be refueled and which we can count on to produce energy at very high efficiency, growing ever greater as the technology progresses? Reliable energy means life is preserved, not put at risk as, I am afraid, is the case with solar and wind if you attempt to use those as baseload power. If solar is used to power remote villagers’ cellphones and lighting so that they have a better standard of living, that is obviously very useful indeed. But don’t try to keep on selling the myth that large cities can run on these power sources without they also having to use vast amounts of fossil fuels as back-up. Only fossil fuels and nuclear can do that job.

      • I did not mean to suggest that a current full solution to our energy needs is now available, ready to go. I did want to point out that there is absolutely more than enough input energy (the sun) to power whatever processes we finally adopt to put in place our next stage of energy infrastructure post fossil-fuel era. Indeed, our renewable power sources are inconveniently distant from and out of time synch from the primary urban centers of demand. For sure we still need to develop meaningful ways to store large amounts of energy near where it is created (synthesized liquid hydrocarbons, pumped uphill water reservoirs, reversed flow cells, etc?) and effective ways to transport them. Invention is still required. But lack of a source of incoming Joules (that’s an energy unit) is not going to be a problem, not now, not ever. Lack of imagination, however …