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Portugal just ran on 100% renewables for six days in a row

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Re: Portugal just ran on 100% renewables for six days in a row

#311

Post by troupo »

Scarblac wrote: post #134
troupo wrote: post #125

Earlier quoted context omitted.

> This is a work in progress, their transition isn't done yet. When will it be done? What really is the answer to the challenge? Germany has ~140 GW of installed renewables when it needs about ~70GW of electricity.

Did you include the electricity needed for when all heating, transport, industry etc is electrified?

Good question as it makes the problem even worse.

When I was writing this (before I forgot to send it on a cloudy morning) 140 GW of installed renewables in Germany are producing a grand total of 14GW of electricity.

Germany needs 61GW.

Right now it looks like all of Europe [1] is busy burning gas and coal because it's cloudy, and there's very little wind.

So what happens when everything becomes electrical? Say, Germany needs 150GW of electricity, builds 500 GW of renewables, but those only produce 50GW (10% of installed capacity, like today)?

[1] Except three countries with stable electricity generation: France (nuclear), Sweden (nuclear + hydro), Norway (hydro)

Re: Portugal just ran on 100% renewables for six days in a row

#312

Post by troupo »

natmaka wrote: post #239
adev_ wrote: post #139

Earlier quoted context omitted.

I am half surprised. People are often shocked when they discover the real number about the Carbon intensity of the German electricity production. There is years of green washing to digest before accepting the truth.

This is not because renewables cannot tackle the challenge, but because this is a work in progress (not quick enough) => not enough electricity produced => it offers a path for coal which is important for social and financial reasons. Add the Ukraine crisis (less imported methane). From 2010 to 2020 (crisis) Germany burnt less and less fossil fuels for its electricity, and methane (gas) isn't booming (from 90 to 96),…

> This is not because renewables cannot tackle the challenge, but because this is a work in progress (not quick enough) => not enough electricity produced

What is the end of this work in progress? 1000% overprovisioning of renewables?

Re: Portugal just ran on 100% renewables for six days in a row

#313

Post by troupo »

KingOfCoders wrote: post #140
troupo wrote: post #128

Earlier quoted context omitted.

In a different discussion a few days ago someone told me I was lying when I pointed out that Germany is burning 20GW of coal to compensate for their 140GW of renewables working at only 15% capacity.

The main challenge is not production but storage - e.g. several people I know have solar panels on their roof, sometimes with 5x their electricity peak usage without a way to store that electricity for later/night usage. The slow uptick of EVs in Germany is partialy part of the problem, it would be the easiest way to increase storage. As a tought experiment, if all cars in Germany would be EVs, those could store 2 da…

> As a tought experiment, if all cars in Germany would be EVs, those could store 2 days of electricity usage.

If you didn't need to, you know, use those cars.

Storage is a huge unsolved problem.

Re: Portugal just ran on 100% renewables for six days in a row

#314

Post by troupo »

hef19898 wrote: post #142
troupo wrote: post #128

Earlier quoted context omitted.

In a different discussion a few days ago someone told me I was lying when I pointed out that Germany is burning 20GW of coal to compensate for their 140GW of renewables working at only 15% capacity.

I wouldn't say lying, but misrepresenting decribes that claim rather well.

Which of the following was misrepresented do you think:

- that Germany has 135 GW combined installed capacity of wind and solar?

- that wind and solar, combined, were only producing 15% of their installed capacity aka 20GW?

- that Germany needed 61 GW of electricity?

- wind and solar, combined, were producing only 30% of Germany's needs?

- that Germany needed to burn 20 GW of coal to cover this?

- that Germany needed to also burn gas, biomass, and import electricity to cover the remaining 20 GW?

Re: Portugal just ran on 100% renewables for six days in a row

#315

Post by troupo »

VaxWithSex wrote: post #148
troupo wrote: post #133

Earlier quoted context omitted.

> Nuclear is emphatically not an instant-on hot backup. Plants take time to spool up, and very importantly time to cool down All modern nuclear plants work in load following mode with ability to change ant the rate of 3-5% of their rated capacity per minute. Graph and text on page 8: https://www.oecd-nea.org/upload/docs/application/pdf/2021-12... > Fukushima happened because you can't just turn a reactor off, Fukushi…

Nobody seems to get that these operational parameters were set and approved and told to be save and then they were still exceeded, lol.

This was literally the definition of a black swan event: "an event that comes as a surprise, has a major effect, and is often inappropriately rationalized after the fact with the benefit of hindsight"

Re: Portugal just ran on 100% renewables for six days in a row

#316

Post by ZeroGravitas »

adev_ wrote: post #75

Meaningwhile, today 17/11/2023 the same Portugal is back to the normal and emitting 170g CO2/kwh [1][2] - This is 6.8x the emissions of Sweden (25g) running on Nuclear and Hydro - This is 4.1x the emissions of France (41g) running on Nuclear, Hydro and Gas - This is 2.8x the emissions of Switzerland (59g) running on Nuclear and Hydro But still much better than "Green" Germany that reaches 647g CO2/kwh.... with 22GW o…

You seem to be making some kind of category error here as "Hydro" is also renewable.

Re: Portugal just ran on 100% renewables for six days in a row

#317

Post by hef19898 »

troupo wrote: post #314
hef19898 wrote: post #142

Earlier quoted context omitted.

I wouldn't say lying, but misrepresenting decribes that claim rather well.

Which of the following was misrepresented do you think: - that Germany has 135 GW combined installed capacity of wind and solar? - that wind and solar, combined, were only producing 15% of their installed capacity aka 20GW? - that Germany needed 61 GW of electricity? - wind and solar, combined, were producing only 30% of Germany's needs? - that Germany needed to burn 20 GW of coal to cover this? - that Germany needed…

The conclsion.

Re: Portugal just ran on 100% renewables for six days in a row

#318

Post by ZeroGravitas »

troupo wrote: post #312
natmaka wrote: post #239

Earlier quoted context omitted.

This is not because renewables cannot tackle the challenge, but because this is a work in progress (not quick enough) => not enough electricity produced => it offers a path for coal which is important for social and financial reasons. Add the Ukraine crisis (less imported methane). From 2010 to 2020 (crisis) Germany burnt less and less fossil fuels for its electricity, and methane (gas) isn't booming (from 90 to 96),…

> This is not because renewables cannot tackle the challenge, but because this is a work in progress (not quick enough) => not enough electricity produced What is the end of this work in progress? 1000% overprovisioning of renewables?

Generally models of fully renewable grids aim for about a 4x overprovisioning (based on peak demand), though of course since that's based on achieving the lowest cost way to provide energy, you could debate whether the phrase "overprovisioning" really applies.

Some have taken to calling it "superpower" (terrible name) because by overbuilding to meet the peak demand, you end up with masses of cheap energy at all non-peak times.

https://www.rethinkx.com/energy

Re: Portugal just ran on 100% renewables for six days in a row

#319

Post by ZeroGravitas »

troupo wrote: post #314
hef19898 wrote: post #142

Earlier quoted context omitted.

I wouldn't say lying, but misrepresenting decribes that claim rather well.

Which of the following was misrepresented do you think: - that Germany has 135 GW combined installed capacity of wind and solar? - that wind and solar, combined, were only producing 15% of their installed capacity aka 20GW? - that Germany needed 61 GW of electricity? - wind and solar, combined, were producing only 30% of Germany's needs? - that Germany needed to burn 20 GW of coal to cover this? - that Germany needed…

> - that wind and solar, combined, were only producing 15% of their installed capacity aka 20GW?

This is a misrepresentation.

Solar for example is only ever planned for to achieve about 30% of its "capacity" (due to the whole sun going down at night thing). And even that varies with seasons.

So if you're claiming the German grid planners were expecting the solar to magically 4x overdeliver, and were suddenly let down then that's nonsense.

Onshore wind has a similar number (again, varies by season).

Re: Portugal just ran on 100% renewables for six days in a row

#320

Post by adrianN »

katbyte wrote: post #187
hef19898 wrote: post #174

Earlier quoted context omitted.

Agree, CO2 emissions are big problem, a life threatening one for some people. Nuclear is a problem too, just not a global obe. You know, both things can be true at the same time. Again, what would be your alternative way forward? Coal and oil burning has to go, that much is sure. We still need electricity so, hence we need clean sources. And we need them fast, because as a species we were asleep at the wheel for way…

There is none except hydro and nuclear for base load. Unless you want to burn gas (co2) or coal (co2 and radioactive emissions that cause more cancers in the us then nuclear has world wide) Renewables outside hydro cannot, and will never, be able to provide a a stable base load for the grid, battery storage isn’t there and has all sorts of issues, pumped storage requires even more rare conditions then hydro, as does…

Hydrogen and gas turbines are proven ways to store large amounts of energy and turn it back into electricity.
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