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Of course, I agree that "total energy balance isn’t a particularly useful metric", given the impact of solar energy ; but picking the right subset is important.
by phtrivier 3y ago
Of course, I agree that "total energy balance isn’t a particularly useful metric", given the impact of solar energy ; but picking the right subset is important.
I would argue that:
* excluding "the energy coming from the sun" is fair game, given that we as a society have very little impact on it
* excluding "the energy not transferred as electricity" is not fair, and misleading, given that it represent a minority of the energy for which the society has a choice.
If [1] gives roughly the correct numbers, Urugay is using ~200TJ/y, and ~40TJ comes from electricity. Not insignificant, and it's the right strategy to replace as much of the remaining 80% by renewables through electricity.
But as long as 20% !== 100%, and as long as people will mis-title articles for no good reason, people will have to correct headlines.
[1] https://www.iea.org/countries/uruguay https://www.iea.org/countries/uruguay
- Retric 3y agoWhere are you getting 200Tj total and 40Tj for electricity? The chart lists 2020 as Hydro 14,738 TJ, biofuels and waste 93,709 TJ, Oil 87,756, Solar/Wind/etc 21,375 TJ, Natural gas 2,504 TJ. So renewables are (14,738 + 93,709 + 21,375 )/ (14,738 + 93,709 + 87,756 + 21,375 + 2,504) = 59% of total energy. However that rather overstates energy from oil. ICE engines are only like 25% efficient but hydro is only counting the fraction of potential energy actually converted to electricity. And even before that refineries waste a lot of energy that’s in oil when producing gasoline. PS: Sanity check electricity consumption is listed as 11.83 TWh * 60m/h * 60s/m * 1j/s = 42,588 TJ/year
- phtrivier 3y agoCorrect, I messed up my units, and miss-interpreted "biofuels and waste". Sorry. Graph is for: Topic: "Energy supply" Indiator: "Total Energy supply (TES) by source". Looking at the stacked chart, for 2020, the sum is above 200 000 TJ (not 200 TJ as I wrote mistakenly). It's propably about 210 000 TJ. Then, for electricity, I summed "Wind, Solar, etc..." (21 375 TJ) and "Hydro" (14 738 TJ). I assumed that "Biofuels and Waste" (93 709 TJ) was used mostly for heating as opposed to electricity generation, and neglected it. It's not entirely the case, though ; in the "Electricity Generation by source", you can see that 2 752 GWh where produced using "biofuels and waste" out of the 811 + 2752 + 4094 + 5476 + 462 = 13595 GWh of electriciy (~20%.) So I guess that we should add ~20% of those 93 709 TJ, and say that roughly (again, I'm doing ballpark computations here) 60 000TJ out of more than 210 000 TJ. Still, 28% !== 100%, isn't it ;) ? --- PS: Out of curiosity, from https://www.iea.org/countries/france https://www.iea.org/countries/france, my home country would be at around 4% renewables, and 40% "non fossil" (given the share of nuclear in electricity), but as usual, we're outliers...
- Retric 3y agoOk, but again don’t forget about efficiency for biofuels. If their Waste power plants are 30% efficient and produce 2.752 TWh that took / 0.3 * 60 * 60 ~= 33,000 Tj of fuel + 42,000 Tj of electricity from other sources. So, (33 PJ + 42 PJ) / 210 PJ = 36% of total primary energy supply used for electricity. Which again shows why comparing pre conversion efficiency numbers to post conversion efficiency numbers gives rather silly results.