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Right. But remember, not all forms of green energy generation are equal. Wind and solar need some dispatchable source as a backup. Hydro works, if you have it.

Right. But remember, not all forms of green energy generation are equal. Wind and solar need some dispatchable source as a backup. Hydro works, if you have it. But it's geographically limited. Gas is the typical backup source, but that emits carbon. Nuclear, as it stands, is the only solution to decarbonizing the energy grid for much of the world. Until some breakthrough in energy storage transpires, or fusion becomes feasible, fission plants remain necessary for decarbonization.

ncmncm 5y ago
Storage is a solved problem, and only needs to be built out. No such "breakthrough" is needed. Storage cost is falling much faster, even, than solar and wind generation. The only question today is whether to put a euro into solar or wind now, or into storage that will be much cheaper next year. Thus far, in most places, the former is still favored. More carbon tax can help move the choice the other way. As solar and wind costs continue down, synthesizing methane and kerosene from captured CO2 and synthetic hydrogen will shortly be cheaper than mining, refining, and transporting them, even without the carbon taxes. Synthesis of those, and of ammonia and hydrogen itself will absorb unlimited "overbuilt" peak generating capacity, and stocks of all of those serve also as storage. That their round-trip efficiency is less than, say, hydro or batteries matters little where they rarely need to be used for that.
- Manuel_D 5y ago
  And which solution is that? Lithium ion batteries? To put this in perspective, global lithium ion battery output [1] annually doesn't amount to 1 hour's worth of US electricity usage (500 GWh). Hydroelectric storage? You essentially need to repurpose an alpine lake as a dam. That's geographically dependent, and it's dubious it'd scale well as viable hydro sites become more and more remote. The remaining things like electricity-to-gas, or thermal storage only exist in prototypes, and might not even be feasible let alone viable. In response to your edit: > As solar and wind costs continue down, synthesizing methane and kerosene from captured CO2 and synthetic hydrogen will shortly be cheaper than mining, refining, and transporting them, even without the carbon taxes. Synthesis of those, and of ammonia and hydrogen itself will absorb unlimited "overbuilt" peak generating capacity, and stocks of all of those serve as storage. Nobody has successfully built a grid-scale energy-to-gas plant, ever. It remains the stuff of prototypes. This approach is very much in the "hypothetical" phase. There are serious unsolved problems in energy-to-gas: * It needs a source of carbon to convert H2 to methane. This could come from biofuels, but those aren't available in sufficient supply. * Producing large quantities of hydrogen without CO2 emissions remains difficult. Almost all methane comes from steam reformation (CH4 + 2O2 -> CO2 + 2H2), which emits carbon dioxide. Electrolysis can't be done effectively. Currently, power to gas storage is way more expensive than either lithium ion or hydroelectric storage and it's unclear whether it'll ever be cheaper than existing options. 1. https://www.spglobal.com/marketintelligence/en/news-insights/blog/top-electric-vehicle-markets-dominate-lithium-ion-battery-capacity-growth https://www.spglobal.com/marketintelligence/en/news-insights...
  - ncmncm 5y ago
    Obviously not lithium batteries. Even suggesting it demonstrates you are not serious. And, obviously hydrogen will not continue to be made from hydrocarbons. It will instead be feedstock for synthesizing hydrocarbons. Carbon would need to be extracted from air, or at least from exhaust, to get carbon credits.
    - Manuel_D 5y ago
      What you're describing is a combination of electrolysis and the Sabatier process [1]. And as I explain before there are major obstacles to actually converting electricity to methane at scale. It needs a source of carbon, and extraction of carbon from the air or exhaust is not feasible. Furthermore, massive electrolysis of hydrogen is also not something we have been able to do. Almost all hydrogen is produced through carbon-emitting steam reformation [2]. In short, converting electricity to methane and then back to electricity again is not a presently available option and it's unclear whether it'll ever be viable at stale. Grid-scale energy storage remains an unsolved problem 1. https://en.wikipedia.org/wiki/Sabatier_reaction https://en.wikipedia.org/wiki/Sabatier_reaction 2. https://en.wikipedia.org/wiki/Hydrogen_production https://en.wikipedia.org/wiki/Hydrogen_production
      - ncmncm 5y ago
        It is fortunate that you are not making decisions, then, for the people who are directing the use of billions of dollars invested in exactly the activities you insist do not work.
        Manuel_D 5y ago
        Are they? Who is building grid-scale power to gas storage?
        ncmncm 5y ago
        The Brits are switching to store wind-generated hydrogen in undersea cavities where they now stockpile natural gas. A similar project is going on in Utah, and another in Texas. All three are utility-scale production systems, not pilot projects. Other storage media being built out for full-scale production use include iron-air batteries, where (IIRC) $1.5B is going into factories, a liquified-air storage system in Chile ($0.5B), and synthetic ammonia in Norway. Nobody can track even a fraction of the utility-scale pumped-hydro projects under construction world-wide. We will need hundreds times as much of these, and of others, in the end, which will all take decades to build out.
- kleene_op 5y ago
  I'll consider storage a solved problem when we actually have it. In the mean time, nuclear is a nice thing to invest in.
  - ncmncm 5y ago
    Each dollar put into building out nuclear instead of renewables + storage brings climate disaster closer. Money is fungible. You cannot spend the same dollar on both. A dollar spent on nukes yields enormously less than the same dollar spent on renewables, and the difference is only growing.
natmaka 5y ago
Even nuclear needs fossil-fuel backup, as building enough reactors to cope with peak demand would be way, way too expensive. Even a massively-nuclearized France produces 7% to 12% of its gridpower thanks to fossil-fuel plants. French official historical data: https://www.statistiques.developpement-durable.gouv.fr/edition-numerique/chiffres-cles-energie-2021/15-electricite https://www.statistiques.developpement-durable.gouv.fr/editi...
- Manuel_D 5y ago
  Nuclear plants can modulate power by more aggressively cooling the reactor. They don't do this because it's effectively wasting nuclear energy, but it can be done.
  - ncmncm 5y ago
    It can be done, but amounts to decreased utilization, and even greater relative incremental cost, because actual operating cost is the same either way. With nukes already the highest-cost choice, intermittent demand makes them even more impractical.
  - natmaka 5y ago
    There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...), and the very combustible status is a major parameter. Pertinent document (French ahead!): https://new.sfen.org/rgn/expertise-nucleaire-francaise-suivi-charge-seduit-europe/ https://new.sfen.org/rgn/expertise-nucleaire-francaise-suivi... « un réacteur peut varier de 100 % à 20 % de puissance en une demi-heure, et remonter aussi vite après un palier d’au moins deux heures, et ce deux fois par jour » 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.

ncmncm 5y ago

Storage is a solved problem, and only needs to be built out. No such "breakthrough" is needed. Storage cost is falling much faster, even, than solar and wind generation. The only question today is whether to put a euro into solar or wind now, or into storage that will be much cheaper next year. Thus far, in most places, the former is still favored. More carbon tax can help move the choice the other way. As solar and wind costs continue down, synthesizing methane and kerosene from captured CO2 and synthetic hydrogen will shortly be cheaper than mining, refining, and transporting them, even without the carbon taxes. Synthesis of those, and of ammonia and hydrogen itself will absorb unlimited "overbuilt" peak generating capacity, and stocks of all of those serve also as storage. That their round-trip efficiency is less than, say, hydro or batteries matters little where they rarely need to be used for that.

Manuel_D 5y ago
And which solution is that? Lithium ion batteries? To put this in perspective, global lithium ion battery output [1] annually doesn't amount to 1 hour's worth of US electricity usage (500 GWh). Hydroelectric storage? You essentially need to repurpose an alpine lake as a dam. That's geographically dependent, and it's dubious it'd scale well as viable hydro sites become more and more remote. The remaining things like electricity-to-gas, or thermal storage only exist in prototypes, and might not even be feasible let alone viable. In response to your edit: > As solar and wind costs continue down, synthesizing methane and kerosene from captured CO2 and synthetic hydrogen will shortly be cheaper than mining, refining, and transporting them, even without the carbon taxes. Synthesis of those, and of ammonia and hydrogen itself will absorb unlimited "overbuilt" peak generating capacity, and stocks of all of those serve as storage. Nobody has successfully built a grid-scale energy-to-gas plant, ever. It remains the stuff of prototypes. This approach is very much in the "hypothetical" phase. There are serious unsolved problems in energy-to-gas: * It needs a source of carbon to convert H2 to methane. This could come from biofuels, but those aren't available in sufficient supply. * Producing large quantities of hydrogen without CO2 emissions remains difficult. Almost all methane comes from steam reformation (CH4 + 2O2 -> CO2 + 2H2), which emits carbon dioxide. Electrolysis can't be done effectively. Currently, power to gas storage is way more expensive than either lithium ion or hydroelectric storage and it's unclear whether it'll ever be cheaper than existing options. 1. https://www.spglobal.com/marketintelligence/en/news-insights/blog/top-electric-vehicle-markets-dominate-lithium-ion-battery-capacity-growth https://www.spglobal.com/marketintelligence/en/news-insights...
- ncmncm 5y ago
  Obviously not lithium batteries. Even suggesting it demonstrates you are not serious. And, obviously hydrogen will not continue to be made from hydrocarbons. It will instead be feedstock for synthesizing hydrocarbons. Carbon would need to be extracted from air, or at least from exhaust, to get carbon credits.
  - Manuel_D 5y ago
    What you're describing is a combination of electrolysis and the Sabatier process [1]. And as I explain before there are major obstacles to actually converting electricity to methane at scale. It needs a source of carbon, and extraction of carbon from the air or exhaust is not feasible. Furthermore, massive electrolysis of hydrogen is also not something we have been able to do. Almost all hydrogen is produced through carbon-emitting steam reformation [2]. In short, converting electricity to methane and then back to electricity again is not a presently available option and it's unclear whether it'll ever be viable at stale. Grid-scale energy storage remains an unsolved problem 1. https://en.wikipedia.org/wiki/Sabatier_reaction https://en.wikipedia.org/wiki/Sabatier_reaction 2. https://en.wikipedia.org/wiki/Hydrogen_production https://en.wikipedia.org/wiki/Hydrogen_production
    - ncmncm 5y ago
      It is fortunate that you are not making decisions, then, for the people who are directing the use of billions of dollars invested in exactly the activities you insist do not work.
      - Manuel_D 5y ago
        Are they? Who is building grid-scale power to gas storage?
        ncmncm 5y ago
        The Brits are switching to store wind-generated hydrogen in undersea cavities where they now stockpile natural gas. A similar project is going on in Utah, and another in Texas. All three are utility-scale production systems, not pilot projects. Other storage media being built out for full-scale production use include iron-air batteries, where (IIRC) $1.5B is going into factories, a liquified-air storage system in Chile ($0.5B), and synthetic ammonia in Norway. Nobody can track even a fraction of the utility-scale pumped-hydro projects under construction world-wide. We will need hundreds times as much of these, and of others, in the end, which will all take decades to build out.
kleene_op 5y ago
I'll consider storage a solved problem when we actually have it. In the mean time, nuclear is a nice thing to invest in.
- ncmncm 5y ago
  Each dollar put into building out nuclear instead of renewables + storage brings climate disaster closer. Money is fungible. You cannot spend the same dollar on both. A dollar spent on nukes yields enormously less than the same dollar spent on renewables, and the difference is only growing.

natmaka 5y ago

Even nuclear needs fossil-fuel backup, as building enough reactors to cope with peak demand would be way, way too expensive. Even a massively-nuclearized France produces 7% to 12% of its gridpower thanks to fossil-fuel plants. French official historical data: https://www.statistiques.developpement-durable.gouv.fr/edition-numerique/chiffres-cles-energie-2021/15-electricite https://www.statistiques.developpement-durable.gouv.fr/editi...

Manuel_D 5y ago
Nuclear plants can modulate power by more aggressively cooling the reactor. They don't do this because it's effectively wasting nuclear energy, but it can be done.
- ncmncm 5y ago
  It can be done, but amounts to decreased utilization, and even greater relative incremental cost, because actual operating cost is the same either way. With nukes already the highest-cost choice, intermittent demand makes them even more impractical.
- natmaka 5y ago
  There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...), and the very combustible status is a major parameter. Pertinent document (French ahead!): https://new.sfen.org/rgn/expertise-nucleaire-francaise-suivi-charge-seduit-europe/ https://new.sfen.org/rgn/expertise-nucleaire-francaise-suivi... « un réacteur peut varier de 100 % à 20 % de puissance en une demi-heure, et remonter aussi vite après un palier d’au moins deux heures, et ce deux fois par jour » 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.