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Heap_Good_Firewater t1_j3wsnz9 wrote

What about cost?

I have heard that CSP is being abandoned because of the massive drop in cost of solar panels.

The energy storage angle is interesting, however.

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Surur t1_j3x9dmx wrote

I wonder how the efficiency compares with using heating the transfer fluid with electricity from PV.

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Zoloir t1_j3xk1ck wrote

if we assume that both water tanks lose heat at the same rate, so our only objective is to turn light into heat, then because solar panels are pretty far from 100% efficient at turning light into electricity, then it is more likely that absorbing all the light on the right surface into heat is probably closer to 100% than absorbing some of it into electricity, and then converting that electricity into heat

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Surur t1_j3xmhiy wrote

The idea is to use excess solar energy heat and store the transfer fluid to generate electricity at night.

Apparently, trough CSP is about 20-40% efficient, and solar cells are about 20% efficient, and turning electricity to heat is 100% efficient, so if the solar cells are 1/2 the price of the troughs, they would be cheaper than the troughs in generating heated fluid for storage.

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Galactus54 t1_j3zgl5h wrote

But since the troughs probably have a much longer usable life their lifetime efficiency surpasses PV.

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-The_Blazer- t1_j3xuayq wrote

It's more expensive than solar PV, but those only look so good because all the infrastructure and storage to actually use them as a primary energy source is not included in the price.

It's the same with offshore wind, nuclear and gas (which if you hear Reddit should have gone extinct 5 years ago): all these sources look worse than solar PV, until you include the cost of having zero power output for half the day or more. I read a study some time ago showing that if you add just 4-6 hours of storage to solar PV the LCOE shoots up to 100$ per megawatt/h. And to endure the winter you'd need more like 16 hours.

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Heap_Good_Firewater t1_j3xvwox wrote

Yeah, solar only really makes sense in really sunny areas.

Germany is learning that the hard way.

The US hasn’t learned it yet. I have seen solar arrays in western Oregon, central Michigan, and Connecticut.

What we really need are more efficient long-distance transmission lines and s smarter grid.

We could then put large solar arrays in the southwest and huge wind farms in the Great Plains and distribute the power where it’s needed.

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netz_pirat t1_j3y1zkk wrote

German here... No we're not? We're installing as many panels as we can.

Rooftop solar comes in at 6ct/kwh here, which is substantially cheaper than coal, gas or nuclear power.

For what it's worth, it's been cheaper to have solar panels create enery for green hydrogen than to buy natural gas for most of the year.

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Heap_Good_Firewater t1_j3y2mmj wrote

German consumption of lignite (dirty coal) has increased sharply since nuclear was largely abandoned.

The price you quoted ignores the cost of backstopping solar at night or on cloudy days.

https://www.bloomberg.com/news/articles/2022-12-22/germany-returns-to-coal-as-energy-security-trumps-climate-goals

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netz_pirat t1_j41a6a5 wrote

The fuck you are talking about? https://en.m.wikipedia.org/wiki/Energy_in_Germany#/media/File%3AEnergy_mix_in_Germany.svg

Coal use has gone down a lot over the years, if anything we burned more coal because we needed to export more energy to France as they had lots of reactor maintenance

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Heap_Good_Firewater t1_j429lhx wrote

The West’s Nuclear Mistake (The Atlantic)

Germany in 2020 was ninth in the world in coal burning. The UK burned barely any coal. The difference was the idiotic decision by Germany to drop nuclear power.

Despite Germany’s PR, their pre-Ukraine emissions reductions have far more to do with demographic decline than alternative energy. German emissions reductions have actually slowed since they started their solar buildout.

Also, Germany counts electricity generation from lignite as “renewable” as long as it is backstopping solar. This vastly overstates their green capacity, as lots of energy is used in the evening.

https://youtu.be/AYu9rliT3F4

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netz_pirat t1_j42kfzb wrote

Demographic decline? Population has been growing.

And no, we don't count coal energy as renewable.

How can one look at YOY 50% renewable electric energy and conclude that this must mean we burn more coal? Wind and solar produce more electricity every year than nuclear ever did

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Sol3dweller t1_j42l276 wrote

Coverage of the Energiewende is almost uniformly negative in the United States. The Atlantic article is just another instance of that PR, as you call it. It's neither particularly well researched (Merkel didn't decide the nuclear phase-out that was put into law already a decade earlier), nor well reasoned (they claim that the decline of nuclear power has not been covered by renewables, based on the observation that coal still is around?). Germany is produced way less electricity from coal in 2021 when that article was published than in 2001 when their nuclear power peaked, and the power output from wind and solar increased more (+106 TWh) than by what nulcear declined (-102 TWh). Power from coal declined even more (-123 TWh).

> The difference was the idiotic decision by Germany to drop nuclear power.

No, the difference is that the UK replaced their coal burning by gas. Similar to the US, however it is further advanced in replacing that gas burning with wind power than the US. Nuclear power output in the UK is also declining. It peaked in 1998 at nearly 100 TWh. In 2021, they produced less than 47 TWh and last year EDF closed Hunterston B (before the Russian invasion) and Hinkley Point B (in August).

>Despite Germany’s PR, their pre-Ukraine emissions reductions have far more to do with demographic decline than alternative energy.

Source? German population isn't really declining, so that seems to be a pretty bad analysis.

>Also, Germany counts electricity generation from lignite as “renewable” as long as it is backstopping solar.

No, it doesn't?

>https://youtu.be/AYu9rliT3F4

That video doesn't seem to care much about facts. France more populous than Germany? Germany gets more than a third of its power from wind+solar alone, not "just 10%". The government states estimated overall costs of 500 billion for the energy transition until 2050. The highest estimate I know of talks about 500 billion until 2025. Where did he pull the 2 trillion from?

Lignite burning in Germany has gone up this year, that's true, it increased by about 5%, but it's not like it would be a new development that they lean heavily on coal burning. They generated 140 TWh from lignite in 2002 when they were close to their nuclear power output compared to 105 TWh in 2022.

It's total nonsense, that only solar power is on the grid, when the sun shines, there just is too little solar power installed yet for that in Germany.

Here is the power production in June 2022. Notice that there isn't just solar+wind on the grid at any point. The claim that the emissions from that coal burning isn't accounted for in the carbon emission figures seems just total fabrication.

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RedditorsArGrb t1_j40jhl9 wrote

This article explicitly attributes Germany burning more coal in 2022 than 2021 to the ongoing natural gas squeeze and French nuclear failures. Germany has been winding down nuclear production for like a decade and coal has trended net negative over that time. Any dumbass can look this up, kind of weird of you to lie about it.

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Heap_Good_Firewater t1_j40scgs wrote

Yes, that wasn’t the best article to use to illustrate my point. Apologies (I was in a hurry and grabbed the wrong link). The 2021-2022 change was from a much higher baseline than it would have been if Germany hadn’t abandoned nuclear power. This article actually addresses my point:

The West’s Nuclear Mistake (The Atlantic)

Germany in 2020 was ninth in the world in coal burning. The UK burned barely any coal. The difference was the disastrous decision by Germany to drop nuclear power.

But nuclear power is dangerous!

The proven death toll from Fukishima is in the single digits. Three Mile Island had zero. Chernobyl killed 60 people almost immediately and maybe several hundred overall, but let's assume 20,000 lives shortened, to accept the absolute worst-case estimates.

All of those deaths together represent fewer deaths than two years of Chinese coal mining. If you factor in the health impacts of coal soot, coal is hundreds of thousands of times more deadly. Full replacement of coal with nuclear might have saved 7 million lives.

https://blogs.scientificamerican.com/the-curious-wavefunction/nuclear-power-may-have-saved-1-8-million-lives-otherwise-lost-to-fossil-fuels-may-save-up-to-7-million-more/

Newer plants can be designed so meltdowns are impossible. High-level nuclear waste can be reprocessed. Being afraid of a modern nuclear power plant is like refusing to fly on a 787 because the Hindenburg crashed.

Yes, there are some outdated plants (or plants in earthquake zones), that probably should be shut down, but we should be building new plants as fast as possible.

France has proven that nuclear power can be safe, economical, and generate minimal high-level waste, but even their technology is out of date.

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Despite Germany’s PR, their pre-Ukraine emissions reductions have far more to do with demographic decline than alternative energy. German emissions reductions have actually slowed since they started their solar buildout.

Also, Germany counts electricity generation from lignite as “renewable” as long as it is backstopping solar. This vastly overstates their green capacity, as lots of energy is used in the evening.

https://youtu.be/AYu9rliT3F4

Why Germany is not as green as you think

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