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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

#151

Post by debok »

KingOfCoders wrote: post #120
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…

Shouldn't that be g/person not g/kwh? E.g. when travelling to the US I was astonished to see escalators going at night with no one around. In Germany they stop at night. Or Germany uses lots of public transport while the US doesn't. Which reflects in the numbers, the US has much higher g/person compared to Germany (Didn't look into Portugal).

I think both metrics have their value. g/kwh gives you nice overview at how clean the energy is, and there is value in optimising that figure.

The problem with measuring CO2 per person is that it is heavily influenced by the wealth level of the country's population. Poor counties have very low CO2 emissions, but people in wealthy countries wouldn't want to trade their living standards for those of a poor country. That would arguably be worse than climate change in the first place.

So optimising for CO2 g/kwh allows us to reduce our emissions without reducing our quality of living. Which is great.

That being said, I agree that running escalators at night is a terrible waste of energy.

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

#152

Post by hef19898 »

KingOfCoders wrote: post #117
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…

`Nuclear "just works"` No it doesn't. Nuclear power plants are nowhere near insured to risk and nuclear waste is not paid for. So nuclear operators are freeloading on society for decades making billions of profits [0]. To make nuclear "work", one would need to adjust insurance and establish a trust to pay for nuclear waste facility operation for the next hundres of years. But then, no one would operate them nuclear p…

The pro-nuclear growd (funny how easy it is for otherwise smart people to be sold on mere talking points) has a point so: during generation a nuclear power plant doesn't emit CO2. What people willfully (?) ignore is the simple fact that a) we don't have enough nuclear capacity installed, and never did and b) you cannot just wish nuclear power plants into existence. The latter being the main blocking point.

Just how you can jump from that to opposing renewables build outs is beyond me. And honestly, nobody is lobbying for new coal plants, except the operators and owners of those plants. And boy, do they have a lobby...

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

#153

Post by vasco »

natmaka wrote: post #121
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…

This is a work in progress, their transition isn't done yet. Without nuclear no risks tied to a major accident, dependancy towards uranium providers, hot waste disposal, overcentralization, overcentralization, proliferation, daunting building and decommission projects... ( https://news.ycombinator.com/item?id=38288706 ) Not a bad deal.

We have all the risks and none of the benefits of nuclear since Spain has a couple surrounding us.

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

#154

Post by hef19898 »

KingOfCoders wrote: post #145
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.

And electricity usage is only a minor part of CO2 production. Primary energy usage in Germany is split 25% is electricity, 25% is traffic and 50% is heating and cooling. As proven by the article the whole discussion is a huge red herring. Amdahl's law applies [0], if I reduce CO2 from electricity production by 50%, my overall reduction is only 12.5% [0] https://en.wikipedia.org/wiki/Amdahl%27s_law

See, that is why the switch to heat pumps for heating makes sonmuch sense: you can store oversupply of renewable electricy in the form of hot water, cutting down significantly on the CO2 emissions currently produced by heating with oil and gas.

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

#155

Post by anovikov »

adev_ wrote: post #116
anovikov wrote: post #111

Earlier quoted context omitted.

Well, they still consume 60% of renewable electricity long term overall, that's not counting whatever renewable electricity may be a part of imports from Spain. It's good enough and that's a big progress. With solar power due to increase more than 7x by 2030 (now generating 8% of all power consumed), and wind by almost 3x with almost all additions being offshore (now generating 18% of all power), it's easy to see tha…

> 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 H…

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".

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

#156

Post by wewxjfq »

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…

> "Green" Germany...

Germany managed to have dirty electricity with nuclear energy, too. Why do people point at Germany and pretend it's a green energy failure, when Germany had a conservative government for 16 years that never cared about green energy? Green energy was never a policy*, what makes Germany the poster-child of a green energy failure? The conservatives said renewables drive electricity prices up and set out to stop them, and around the time they shut down nuclear power plants, they considered it an achievement to have prevented new photovoltaic installations.

* Germany had exactly one government that put their faith in renewables and that was a noble goal, considering that renewables were at the very bottom of the S-curve, which also means that one could only make babysteps towards green energy. Now we're in the middle of the S-curve and countries can add GWs of renewables to their grid, which makes Germany's early attempts look pathetic, but you simply can't move at that pace at the bottom of the curve.

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

#157

Post by hef19898 »

epups wrote: post #147
adev_ wrote: post #129

Earlier quoted context omitted.

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 sho…

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.

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?

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

#158

Post by himinlomax »

icy_deadposts wrote: post #143
adev_ wrote: post #80

Earlier quoted context omitted.

Would people that minus a post stating facts backed by sources deign to explain why ? I am aware that reality can be harsh to accept sometimes. And that a world where renewable are our only source of energy is more seducing to our collective imagination. But unfortunately, it is still the reality. And we have to deal with it, even if it is pretty unpleasant.

Here's a harsh reality: "zero co2" nuclear emits massive amounts of CO2 during mining, during enrichment, creation of fuels, the massive motorcades that transport the fuels to their final power plant destination where they finally produce power without emitting CO2. So maybe its better for local air quality, but really the emissions are quite high. The actual metric that reflects the total embodied energy, which is a…

> Here's a harsh reality: "zero co2" nuclear emits massive amounts of CO2 during mining, during enrichment, creation of fuels, the massive motorcades that transport the fuels to their final power plant destination where they finally produce power without emitting CO2. So maybe its better for local air quality, but really the emissions are quite high.

That's complete bollocks, because all those CO₂ emissions are proportional to the amount of fuel, and the power density of nuclear fuel is such that the total amount is indeed tiny.

Solar panels and wind turbines also require emitting CO₂ for their manufacture, and it turns out that they emit more than nuclear, fuel included.

Additionally, while enrichment requires a lot of energy, to spin turbines or fuel gas separation, it's electrical energy, and in France for instance it's nuclear energy fueling enrichment.

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

#159

Post by realusername »

hef19898 wrote: post #135
realusername wrote: post #131

Earlier quoted context omitted.

Yeah no risk of a major accident ... apart from climate change you know. If Germany could at least reach the 90s levels of France, that's why I would consider that some work in progress already

I love that, you know? You have some good news regarding electricity and renewables, and instead of being happy, people start to look for problems. But let's role with it for second. Renewables are, unfortunately, not at a point yet where they can cover 100% of demand. We cannot change the current mix neither. So, what would be your proposed way forward to "solve" climate change? I am really curious, because most of…

I'm the kind of "I'll believe it when I see it" type of person. The transition is clearly not going well and they even wanted to build more gas pipes, the russian war lessons have not been learned. Renewables in the EU overpromissed and underdelivered for a long time.

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

#160

Post by vasco »

pmoleri wrote: post #32
barney54 wrote: post #24

Earlier quoted context omitted.

We still neglect what? There is incredible pressure to build renewables.

Ask the countries that keep building coal and gas power plants, polluting the only planet we have.

If only they all listened to you! I don't have all the answers but a few of the ones I researched that are being built are needed to ensure people have heating through the winter in the next 3-7 years until reliable other solutions appear.
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