5 ms·

Source? None of those are meant to be sufficient ( https://en.wikipedia.org/wiki/Nirvana_fallacy https://en.wikipedia.org/wiki/Nirvana_fallacy ), as for any sy

Source? None of those are meant to be sufficient ( https://en.wikipedia.org/wiki/Nirvana_fallacy https://en.wikipedia.org/wiki/Nirvana_fallacy ), as for any system this is for the complete set of ways to reach the 'good enough' stage: a continental ( https://www.imperial.ac.uk/news/180592/european-cooperation-could-provide-more-stable/ https://www.imperial.ac.uk/news/180592/european-cooperation-... ) mix (wind, solar, geothermal, biomass...) backed up by storage, clean backup (green hydrogen)...

realusername 2y ago
The source is your own link, the biggest US battery can sustain a few minutes of the country's consumption. We aren't in the "good enough" stage but more "we need a breakthrough" stage. We are multiple orders of magnitude away to use those at a large scale. For green hydrogen that's pretty much the same issue, the efficiency is beyond terrible and we would need another breakthrough there. That's why no country on earth is managing with those.
- natmaka 2y ago
  Which source states that more than a few minutes will be necessary, once the adequate continental system (storage: including V2G and similar ways such as Powerwalls) will be in place? > the efficiency is beyond terrible ... when used in transportation. Green hydrogen produced then stored nearby a turbine or fuel cell acting as backup for the grid efficiency is similar to fossil fuels' or nuclear (about .3 to .4). > That's why no country on earth is managing with those. No, that's because all this (especially industrial renewable sources, really soaring in the 2000's) is too new, this is a work in progress starting with production: https://ourworldindata.org/grapher/electricity-fossil-renewables-nuclear-line https://ourworldindata.org/grapher/electricity-fossil-renewa...
  - realusername 2y ago
    > Which source states that more than a few minutes will be necessary, once the adequate continental system (storage: including V2G and similar ways such as Powerwalls) will be in place? Ever looked at an electricity demand graph? The electricity demand isn't linear, it's not linear in a day, not linear in a week and especially not linear in months either in the northen hemisphere. And the more you decarbonize the economy, the worse it's going to get for renewables here since fossil fuels are used for highly non linear usage. > Green hydrogen produced then stored nearby a turbine or fuel cell acting as backup for the grid efficiency is similar to fossil fuels' or nuclear (about .3 to .4). You are mixing up two things. Nuclear, since it's a baseload technology, only needs to adapt itself to the demand, the production can mostly be planned. Renewables on the other hand need to adapt both the demand and the production. Those efficiencies figures aren't needed for nuclear because you don't need P2G or any of that, you can just adjust the production. So you get the usual production. Nuclear doesn't drop abruptly to 5% capacity and those bandaid solutions aren't really needed. What you are quoting is the efficiency of the production, which is a totally different subject. The efficiency of the production is more of an indication of how far you can actually go in the future.
    - natmaka 2y ago
      > the more you decarbonize the economy, the worse it's going to get for renewables here since fossil fuels are used for highly non linear usage. A continental spread-out mix (wind, solar, hydro, geothermal, biomass...) reduces production variability ( this is tru even considering a single type of source: https://www.imperial.ac.uk/news/180592/european-cooperation-could-provide-more-stable/ https://www.imperial.ac.uk/news/180592/european-cooperation-... ) Overproduced electricity can be stored. V2G will play a major role. > You are mixing up two things I doubt so. I was stating that hydrogen may become a clean backup, replacing fossil-fuel existing plants, some of them (burning methane) may be retrofitted. Water electrolysis done in centralized plants gathering electricity overproduced at continental level in order to obtain and locally temporarily store hydrogen, maybe even benefiting from co-generation, will locally burn it (gas turbine or fuel cell) in order to produce electricity when the grid needs it while renewable sources cannot provide enough. > aren't needed for nuclear because you don't need P2G or any of that, you can just adjust the production Nuclear can 'modulate' its output up to a certain level and frequency, which in practice are insufficient. Even over-nuclearized France never enjoyed a zero-carbon grid: each year between 6% and 12% of electricity is produced by burning fossil fuel ( https://ourworldindata.org/explorers/energy?Metric=Share+of+total+generation&Total+or+Breakdown=Select+a+source&Energy+or+Electricity=Electricity+only&Select+a+source=Fossil+fuels&tab=chart&country=~FRA https://ourworldindata.org/explorers/energy?Metric=Share+of+... ) because exploiting enough reactors to cope with the mandatory load-following and also with the peak load would be way too expensive. There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...) to nuclear load-following capacity, and the very combustible status is a major parameter. Pertinent document (French ahead!): https://www.sfen.org/rgn/expertise-nucleaire-francaise-suivi-charge-seduit-europe/ https://www.sfen.org/rgn/expertise-nucleaire-francaise-suivi... Proposed translation: "a reactor power output can vary from 100% to 20% in 30 minutes, then after 2 hours can go back to 100% at the same speed, and can cycle this way 2 times per day". This is quite a good performance when it comes to load-following (French engineers are very good at this), however it is insufficient in the real world (save any ridiculously expensive over-provision of nuclear reactor, most idling) and very weak compared to gas turbines performances. Those "bandaid" solution are needed with each and every low-carbon type of source, even nuclear. We have to consider the amount of emissions caused, in each type of system, by those solutions. On a grid when it comes to the "production = consumption" rule there are 2 big types of challenge: 1/ short-term adjustment (under a few seconds). Nuclear, per se, just cannot cope. It is done by the sheer inertia of the turbo-alternator drive shaft. On a renewable system it can also be done this way, thanks to flywheels. It is already done. 2/ long-term adjustments. It is either done by reducing the output of production units, or storing or wasting it or (if production isn't sufficient), by a reserve of "production" units (batteries, green hydrogen turbines...).

realusername 2y ago

The source is your own link, the biggest US battery can sustain a few minutes of the country's consumption. We aren't in the "good enough" stage but more "we need a breakthrough" stage. We are multiple orders of magnitude away to use those at a large scale. For green hydrogen that's pretty much the same issue, the efficiency is beyond terrible and we would need another breakthrough there. That's why no country on earth is managing with those.

natmaka 2y ago
Which source states that more than a few minutes will be necessary, once the adequate continental system (storage: including V2G and similar ways such as Powerwalls) will be in place? > the efficiency is beyond terrible ... when used in transportation. Green hydrogen produced then stored nearby a turbine or fuel cell acting as backup for the grid efficiency is similar to fossil fuels' or nuclear (about .3 to .4). > That's why no country on earth is managing with those. No, that's because all this (especially industrial renewable sources, really soaring in the 2000's) is too new, this is a work in progress starting with production: https://ourworldindata.org/grapher/electricity-fossil-renewables-nuclear-line https://ourworldindata.org/grapher/electricity-fossil-renewa...
- realusername 2y ago
  > Which source states that more than a few minutes will be necessary, once the adequate continental system (storage: including V2G and similar ways such as Powerwalls) will be in place? Ever looked at an electricity demand graph? The electricity demand isn't linear, it's not linear in a day, not linear in a week and especially not linear in months either in the northen hemisphere. And the more you decarbonize the economy, the worse it's going to get for renewables here since fossil fuels are used for highly non linear usage. > Green hydrogen produced then stored nearby a turbine or fuel cell acting as backup for the grid efficiency is similar to fossil fuels' or nuclear (about .3 to .4). You are mixing up two things. Nuclear, since it's a baseload technology, only needs to adapt itself to the demand, the production can mostly be planned. Renewables on the other hand need to adapt both the demand and the production. Those efficiencies figures aren't needed for nuclear because you don't need P2G or any of that, you can just adjust the production. So you get the usual production. Nuclear doesn't drop abruptly to 5% capacity and those bandaid solutions aren't really needed. What you are quoting is the efficiency of the production, which is a totally different subject. The efficiency of the production is more of an indication of how far you can actually go in the future.
  - natmaka 2y ago
    > the more you decarbonize the economy, the worse it's going to get for renewables here since fossil fuels are used for highly non linear usage. A continental spread-out mix (wind, solar, hydro, geothermal, biomass...) reduces production variability ( this is tru even considering a single type of source: https://www.imperial.ac.uk/news/180592/european-cooperation-could-provide-more-stable/ https://www.imperial.ac.uk/news/180592/european-cooperation-... ) Overproduced electricity can be stored. V2G will play a major role. > You are mixing up two things I doubt so. I was stating that hydrogen may become a clean backup, replacing fossil-fuel existing plants, some of them (burning methane) may be retrofitted. Water electrolysis done in centralized plants gathering electricity overproduced at continental level in order to obtain and locally temporarily store hydrogen, maybe even benefiting from co-generation, will locally burn it (gas turbine or fuel cell) in order to produce electricity when the grid needs it while renewable sources cannot provide enough. > aren't needed for nuclear because you don't need P2G or any of that, you can just adjust the production Nuclear can 'modulate' its output up to a certain level and frequency, which in practice are insufficient. Even over-nuclearized France never enjoyed a zero-carbon grid: each year between 6% and 12% of electricity is produced by burning fossil fuel ( https://ourworldindata.org/explorers/energy?Metric=Share+of+total+generation&Total+or+Breakdown=Select+a+source&Energy+or+Electricity=Electricity+only&Select+a+source=Fossil+fuels&tab=chart&country=~FRA https://ourworldindata.org/explorers/energy?Metric=Share+of+... ) because exploiting enough reactors to cope with the mandatory load-following and also with the peak load would be way too expensive. There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...) to nuclear load-following capacity, and the very combustible status is a major parameter. Pertinent document (French ahead!): https://www.sfen.org/rgn/expertise-nucleaire-francaise-suivi-charge-seduit-europe/ https://www.sfen.org/rgn/expertise-nucleaire-francaise-suivi... Proposed translation: "a reactor power output can vary from 100% to 20% in 30 minutes, then after 2 hours can go back to 100% at the same speed, and can cycle this way 2 times per day". This is quite a good performance when it comes to load-following (French engineers are very good at this), however it is insufficient in the real world (save any ridiculously expensive over-provision of nuclear reactor, most idling) and very weak compared to gas turbines performances. Those "bandaid" solution are needed with each and every low-carbon type of source, even nuclear. We have to consider the amount of emissions caused, in each type of system, by those solutions. On a grid when it comes to the "production = consumption" rule there are 2 big types of challenge: 1/ short-term adjustment (under a few seconds). Nuclear, per se, just cannot cope. It is done by the sheer inertia of the turbo-alternator drive shaft. On a renewable system it can also be done this way, thanks to flywheels. It is already done. 2/ long-term adjustments. It is either done by reducing the output of production units, or storing or wasting it or (if production isn't sufficient), by a reserve of "production" units (batteries, green hydrogen turbines...).