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Not disagreeing with your post here but curious about this point: > Steve Keen (amongst others) shows that economic productivity scales near-linearly with ener

Not disagreeing with your post here but curious about this point: > Steve Keen (amongst others) shows that economic productivity scales near-linearly with energy consumption, yet we are using fossil fuels at rates millions of times greater than they accumulated. The only way I can see (without spending more than just a few minutes thinking about this comment) this being true is with 100% efficiency and I wonder if that's the underlying assumption here. I'd hazard a guess that we're using fossil fuels at low single digit percentage efficiency if that and perhaps even putting more in than we're getting out. To your point though, since we're using fossil fuels way faster than they accumulated there's just no way to escape "running out" [1]. Just a matter of when. [1] I don't think we'll ever run out of course, it'll just be more and more expensive. When I think about running out I think about not having society able to adapt to the cost because of how we've built and designed our infrastructure. The US is particularly screwed here since we rely on them so much.

dredmorbius 3y ago
Steve Keen, Robert U. Ayres, Russell Standish, "A Note on the Role of Energy in Production" (March 2019): Energy plays no role in the standard Cobb-Douglas Production Function (CDPF), and a trivial role in a three-factor CDPF where it is treated as a third input, independent of labour and capital. Starting from an epistemological perspective, we treat energy as an input to both labour and capital, without which production is impossible. We then derive an energy-based CPDF (EBCDPF) in which energy plays a critical role. We argue for the redefinition and measurement of real GDP in terms of exergy. We conclude that the “Solow Residual” measures the contribution of exergy to growth, and that the exponents in the EBCDPF should be based on cross-country comparative data as suggested by Mankiw (1995) rather than the “cost-share theorem”. <https://www.sciencedirect.com/science/article/abs/pii/S0921800917311746?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S09218...> For an excellent discussion of efficiency of energy use over time, see Vaclav Smil's Energy and Civilization (2017), which shows the actual attained efficiencies of various fuels usage. <https://en.wikipedia.org/wiki/Energy_and_Civilization:_A_History https://en.wikipedia.org/wiki/Energy_and_Civilization:_A_His...> <https://mitpress.mit.edu/9780262536165/energy-and-civilization/ https://mitpress.mit.edu/9780262536165/energy-and-civilizati...> Note that due to conversion efficiency limits, most generally those of Carnot engines, achieved efficiency in converting thermal to mechanical energy trends around 30%. That can go higher in some applications (e.g., dual-cycle steam turbines combined with usage of residual thermal heat in cogeneration plants). But for the most part large-scale modeling relies on the 30% figure. See for example the Lawrence Livermore Labs energy-flow Sankey charts, in which ~30% efficiency simply assumed for the model, rather than explicitly measured, based on modeling: End-use efficiency is estimated at 65% for the residential sector, 65% for the commercial sector, 21% for the transportation sector, and 49% for the industrial sector, which was updated in 2017 to reflect DOE's analysis of manufacturing. <https://flowcharts.llnl.gov/sites/flowcharts/files/styles/orig/public/2022-04/Energy_2021_United-States.png?itok=kpDvB1lu https://flowcharts.llnl.gov/sites/flowcharts/files/styles/or...> <https://gs.llnl.gov/energy-homeland-security/energy-security/energy-flow-charts https://gs.llnl.gov/energy-homeland-security/energy-security...> TL;DR: results are based on overall inputs and outputs, don't get caught up in considering minutiae of conversion efficiencies.

dredmorbius 3y ago

Steve Keen, Robert U. Ayres, Russell Standish, "A Note on the Role of Energy in Production" (March 2019): Energy plays no role in the standard Cobb-Douglas Production Function (CDPF), and a trivial role in a three-factor CDPF where it is treated as a third input, independent of labour and capital. Starting from an epistemological perspective, we treat energy as an input to both labour and capital, without which production is impossible. We then derive an energy-based CPDF (EBCDPF) in which energy plays a critical role. We argue for the redefinition and measurement of real GDP in terms of exergy. We conclude that the “Solow Residual” measures the contribution of exergy to growth, and that the exponents in the EBCDPF should be based on cross-country comparative data as suggested by Mankiw (1995) rather than the “cost-share theorem”. <https://www.sciencedirect.com/science/article/abs/pii/S0921800917311746?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S09218...> For an excellent discussion of efficiency of energy use over time, see Vaclav Smil's Energy and Civilization (2017), which shows the actual attained efficiencies of various fuels usage. <https://en.wikipedia.org/wiki/Energy_and_Civilization:_A_History https://en.wikipedia.org/wiki/Energy_and_Civilization:_A_His...> <https://mitpress.mit.edu/9780262536165/energy-and-civilization/ https://mitpress.mit.edu/9780262536165/energy-and-civilizati...> Note that due to conversion efficiency limits, most generally those of Carnot engines, achieved efficiency in converting thermal to mechanical energy trends around 30%. That can go higher in some applications (e.g., dual-cycle steam turbines combined with usage of residual thermal heat in cogeneration plants). But for the most part large-scale modeling relies on the 30% figure. See for example the Lawrence Livermore Labs energy-flow Sankey charts, in which ~30% efficiency simply assumed for the model, rather than explicitly measured, based on modeling: End-use efficiency is estimated at 65% for the residential sector, 65% for the commercial sector, 21% for the transportation sector, and 49% for the industrial sector, which was updated in 2017 to reflect DOE's analysis of manufacturing. <https://flowcharts.llnl.gov/sites/flowcharts/files/styles/orig/public/2022-04/Energy_2021_United-States.png?itok=kpDvB1lu https://flowcharts.llnl.gov/sites/flowcharts/files/styles/or...> <https://gs.llnl.gov/energy-homeland-security/energy-security/energy-flow-charts https://gs.llnl.gov/energy-homeland-security/energy-security...> TL;DR: results are based on overall inputs and outputs, don't get caught up in considering minutiae of conversion efficiencies.