3 ms·

> it's easy to see that even we assume 50% curtailment rate, It is now 07h00 in Portugal. - Solar production is reduced to 0% because it is night time. Like

by adev_ 3y ago

> it's easy to see that even we assume 50% curtailment rate, It is now 07h00 in Portugal. - Solar production is reduced to 0% because it is night time. Like it is 30% of the time. - Wind is not blowing much. Wind production is at 3.14% of its total capacity. To compensate that, 29% of the production is guarantee by Gas powerplant. The rest from Hydro. To compensate its high Hydro consumption, Portugal is also doing Hydro storage for around 500 MW by Night using electricity imported from Spain. Spanish Electricity is produced around 25% from Gas, which makes the entire operation looks pretty much like Greenwashing. The situation is not exceptional. It can in fact happen for weeks when an heavy depression exist in northern Atlantic. So please, tell me again: How easy will it be to achieve 100% renewable we assume 50% curtailment rate ? Shall Portugal increase its Wind capacity again by 20x ? Can Hydro storage powered by Gas powerplants ever be considered "Green" ? Or Shall we maybe rely on future magical Hydrogen electrolyser that do not exist yet to solve 22 GW of coal power consumption like Germany ?

adrianN 3y ago
You build something like 3x peak demand and produce hydrogen or ammonia while you have a surplus so that you can burn it while the sun doesn't shine and the wind doesn't blow or use it as feedstock for your industrial processes. Industrial scale hydrogen electrolyzers exist, we just need to build more of them once we have a steady electricity surplus that allows us to run them economically.
- KingOfCoders 3y ago
  In 20y we'll have much more solar energy produced than we could use.
- troupo 3y ago
  "Just"
- adev_ 3y ago
  And that is what you qualify "easy" ? Replacing 30% of a country grid capacity by an unproven technology never tested at scale. Associated with an hydrogen storage capacity (which we already struggle to do in labs and in the rocket industry) large enough to substain weeks of productions never also not tested at scale is easy ? All of that should also be cost efficient right ? And if I follow your initial post, it should be solved in the incoming years right ? You see, that summarize quite a lot of my problems with the "all renewable evangelism".
  - epups 3y ago
    Every single energy thread in HN ends like this. Renewable fanatics get backed into a corner when they realize that it is impossible to run a grid on solar and wind alone. Then they start talking about things that currently cannot account for even 0.001% of our global energy storage needs, like hydrogen or batteries.
    - hef19898 3y ago
      Backed into a corner? This thread basically started with "Portugal ran on 100% renewables"... Sobat least for one point in time, it is possible. There are two options now: Take it from there and figure out options to make that one point in time sustainable all the time (requires real engineering and creativity, and time and money). Or throw our hands up, blame environmentalists for shuting down nuclear plants (which wasn't always environmentalists, nor did we ever have enough nuclear plants to begin with). Guess which approach gives us a way forward?
      - epups 3y ago
        > Backed into a corner? This thread basically started with "Portugal ran on 100% renewables"... Sobat least for one point in time, it is possible. Sure, but that's not sustainable, as the numbers on the parent comment clearly indicate. From that perspective, what gives us a way forward is acknowledging that headlines such as these are meaningless in the grand scheme of things, and trying to design an energy strategy that is compatible with the facts at hand.
        hef19898 3y ago
        This strategy already exists so: more renewables, heat pumps for heating, EVs, green hydrogen, flatten peak demand by making industrial demand more flexible. That strategy actually does work, it requires a ton of investment, and time, to scale so. Throw in existing nuclear as stop gap solution. Besides being contrarian, which I get because I have the same tendencies, what would be your alternative? Not doing anything is obviously bad, new nuclear power plants take too long to build and are too expensive (all numbers prove that). So? Any other ideas?
anovikov 3y ago
Very simply - vastly increase hydro generation capacity by adding extra turbines to existing hydro powerplants. You can't increase overall amounts of electricity produced this way because water in dams is finite, but you can increase max power output when needed. This costs a tiny amount compared to digging up dams themselves, displacing businesses and people on the lands to be flooded, buying up land etc. because the footprint of the hydro powerplant doesn't change. In some countries that's a problem because they don't have enough water. Portugal is lucky with that. Water in dams provides seasonal storage of a sort (even if it's never literally pumped up - just used only when necessary, on a high throughput if need be). It will also mean that at daytime and overnight when wind is strong, hydro plants will completely stop. ...In fact, that seems already done. Portugal has 7.6GW of hydro capacity, up from 5GW in 2008. This allows for peak hydro production to cover 1.37 of average and almost entirety of peak electricity consumption in the country. So the answer is very trivial: "when situations like today happen, just use hydro, and don't use hydro in other situations when either wind or solar are available".

by adev_ 3y ago

adrianN 3y ago

You build something like 3x peak demand and produce hydrogen or ammonia while you have a surplus so that you can burn it while the sun doesn't shine and the wind doesn't blow or use it as feedstock for your industrial processes. Industrial scale hydrogen electrolyzers exist, we just need to build more of them once we have a steady electricity surplus that allows us to run them economically.

KingOfCoders 3y ago
In 20y we'll have much more solar energy produced than we could use.
troupo 3y ago
"Just"
adev_ 3y ago
And that is what you qualify "easy" ? Replacing 30% of a country grid capacity by an unproven technology never tested at scale. Associated with an hydrogen storage capacity (which we already struggle to do in labs and in the rocket industry) large enough to substain weeks of productions never also not tested at scale is easy ? All of that should also be cost efficient right ? And if I follow your initial post, it should be solved in the incoming years right ? You see, that summarize quite a lot of my problems with the "all renewable evangelism".
- epups 3y ago
  Every single energy thread in HN ends like this. Renewable fanatics get backed into a corner when they realize that it is impossible to run a grid on solar and wind alone. Then they start talking about things that currently cannot account for even 0.001% of our global energy storage needs, like hydrogen or batteries.
  - hef19898 3y ago
    Backed into a corner? This thread basically started with "Portugal ran on 100% renewables"... Sobat least for one point in time, it is possible. There are two options now: Take it from there and figure out options to make that one point in time sustainable all the time (requires real engineering and creativity, and time and money). Or throw our hands up, blame environmentalists for shuting down nuclear plants (which wasn't always environmentalists, nor did we ever have enough nuclear plants to begin with). Guess which approach gives us a way forward?
    - epups 3y ago
      > Backed into a corner? This thread basically started with "Portugal ran on 100% renewables"... Sobat least for one point in time, it is possible. Sure, but that's not sustainable, as the numbers on the parent comment clearly indicate. From that perspective, what gives us a way forward is acknowledging that headlines such as these are meaningless in the grand scheme of things, and trying to design an energy strategy that is compatible with the facts at hand.
      - hef19898 3y ago
        This strategy already exists so: more renewables, heat pumps for heating, EVs, green hydrogen, flatten peak demand by making industrial demand more flexible. That strategy actually does work, it requires a ton of investment, and time, to scale so. Throw in existing nuclear as stop gap solution. Besides being contrarian, which I get because I have the same tendencies, what would be your alternative? Not doing anything is obviously bad, new nuclear power plants take too long to build and are too expensive (all numbers prove that). So? Any other ideas?

anovikov 3y ago

Very simply - vastly increase hydro generation capacity by adding extra turbines to existing hydro powerplants. You can't increase overall amounts of electricity produced this way because water in dams is finite, but you can increase max power output when needed. This costs a tiny amount compared to digging up dams themselves, displacing businesses and people on the lands to be flooded, buying up land etc. because the footprint of the hydro powerplant doesn't change. In some countries that's a problem because they don't have enough water. Portugal is lucky with that. Water in dams provides seasonal storage of a sort (even if it's never literally pumped up - just used only when necessary, on a high throughput if need be). It will also mean that at daytime and overnight when wind is strong, hydro plants will completely stop. ...In fact, that seems already done. Portugal has 7.6GW of hydro capacity, up from 5GW in 2008. This allows for peak hydro production to cover 1.37 of average and almost entirety of peak electricity consumption in the country. So the answer is very trivial: "when situations like today happen, just use hydro, and don't use hydro in other situations when either wind or solar are available".