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Post by cyrilr on Apr 8, 2024 17:35:15 GMT 9.5
Not that impressive. Under 1% of UK electric demand. The article misleadingly quotes regional power demand and the silly households fallacy. The real question going forward is how UK is going to phase out natural gas. Wind and solar need it. Even tidal needs it; the tides are not synchronized to diurnal or seasonal demand. This is a classic natural gas lock-in playing out right in front of everyone without anyone noticing.
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Post by cyrilr on Mar 20, 2024 21:51:49 GMT 9.5
36 mW/cm2 so about 36% efficient if that is monofacial. And nearly 100% bifaciality. Using a few nanometers of material. This sounds to good to be true. What’s the catch? How much does it degrade per year?
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Post by cyrilr on Nov 28, 2023 19:46:00 GMT 9.5
Sorry David, but I won’t waste any more time with you on this.
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Post by cyrilr on Nov 28, 2023 0:40:48 GMT 9.5
Oh dear! Both cyrilr and Roger Clifton are misinformed: 1. Capacity factor for solar PV depends upon where it is installed. It might be as high as 25% in the desert but is much less here in the Pacific Northwest, so much so that it is only this year that it pays to install some solar panels on one’s roof. This is, of course, treated as independent from the degradation over time of solar PV. The latter is an important consideration in determining the payback period. 2. It is well known that adding a battery to a solar PV installation pays for itself by making the power available when it is needed — in the later afternoon and early evening in localities which require air conditioning. 3. Solar PV and wind are replacing coal burners in many regions of the world. For example, Australia, for which there is a separate thread here @ Brave New Climate Discussion Forum devoted to reports about how well that is working. And it is no surprise that solar PV is not well suited to wherever in northern Europe cyrilr hails from. 4. The central point of my post is that we now have confirmation that solar PV panels last for at least 25 years without signifiant degradation in performance. That’s all. Sadly it is you who is misinformed. Totally missing the point of capacity vs generation. And still no numbers on actual lifetime energy generated for that facility, which you could have made an effort in looking up instead of pointing out some tangential/blatantly obvious side points. And as to battery paying for itself... that is a lie. Batteries add cost. They do not reduce cost. Batteries are very expensive. So we can’t draw any useful conclusions. And as a secondary point, 20% loss of output is rather serious, given that fossil plants lose nothing and nukes actually generally increase output over their life. You’re a smart guy, so I’m going to accuse you of either trolling.or just being deliberate obtuse. Which is it? Do you understand why talking about nameplate capacity for an energy source that has no capacity is an attempt at deliberate obfuscation? This is THE key problem with solar that you just try to fast talk your way out of. As to coal replacement - sure, if you have a lot of natural gas or other firm capacity. Solar can’t do it on its own w/o natural gas. If anything Australia and the UK are proof. And actually no Australia is not proof - Australia coal production is going up. They will export it. They will use natural gas with some solar and wind for greenwashing while increasing coa exports. Net is an increase in global CO2 emissions. This is not a good case study in going green!
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Post by cyrilr on Nov 26, 2023 21:26:23 GMT 9.5
Capacity factor isn’t even mentioned in the article. Yes, the word "capacity" should always be appended. Let's remember that these guys (PV-mag etc) are in the business of selling religious junk to the doomed. As a marketing machine, they are dedicated to misleading the public. They perpetuate the meme that if we buy enough of their junk, we will have reliable fossil-free electricity on tap. Yeah, sure. Bathed in the smooth patter, we are to feel forgiven for the emissions that we continue to make – junk, or no junk. When anyone in the renewables camp fails to append the word "capacity", we should assume immediately that it is deceit underway and that someone is being defrauded. Then if we can spare the time, to ask questions later. Well put, Roger! The lack of critical review in all these PV magazines and websites is rather shocking. Everything is sunshine and rainbows, innovation is amazing, bla bla. Meanwhile the performance figures are dismal. Right now solar PV is running at about 1% capacity factor this month over here, and will do the same next month. These are national figures, not cherry picking. It is the reality of solar PV in northern European winter. If I were writing an article about the oldest PV plant in a country, the first question that comes to mind is how much energy has been generated by the facility. It's the key performance metric, and we can derive useful statistics from it using back of the envelope calculations that an 8 year old could do. It is sad to see this is beyond the capability of the PV magazines. The state of solar PV is that cost have dropped a lot so a lot of people installed solar PV, to the point of there being too much power at noon in summer resulting in negative prices. Mr. Market telling us to please stop installing more PV systems onto the grid. Meanwhile no fossil plants are being shut. I think we have over 10000 MW of solar PV now. Hasn't resulted in any fossil plants shut down and CO2 emissions are almost the same. That is the real state of solar PV that the advocates won't tell. To fix these issues one needs extreme levels of energy storage which is cost prohibitive, not to mention environmentally exhausting on non renewable resources. We are supposed to save the environment, not pillage it for ever more resources. I'm not totally antagonistic towards PV though. There could be some large scale uses such as making ice or chilled water for airconditioning. And satellite communications would be hard without it. To me, the whole grid connected PV thing is just taking a good idea to the extreme where it becomes a bad idea. And it is surrounded by more bad ideas like distributed power generation, and a general emotion of antagonizing the "evil power utilities". Very popular with academics and dreamers, just not practical from the engineering and numbers angle.
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Post by cyrilr on Nov 26, 2023 19:52:47 GMT 9.5
No. It is currently night time in Brazil so it runs at 0%. It may run at 80% power for an hour on a sunny summer day. This isn’t pedantism. The capacity factor isn’t even mentioned in the article. Sorry, cyrilr, but yours is pedantism of the first order. As I write this, the sun is shining in Brazil and so the panel is producing. Given the current illumination and angle of the sun, the panel is producing 80% of the power it originally did 26 years ago, it’s rated power. It isn’t pedantism. An article claiming how long lived PV is should mention the basic performance figures, least of which would be how much energy the facility has provided over the lifetime. I was merely pointing out that simple fact of journalism 101, but you had to be a pedant by missing the key point. And if you don’t understand why rated nameplate power is not an appropriate performance metric for PV then my point is lost to you to begin with.
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Post by cyrilr on Nov 25, 2023 20:12:41 GMT 9.5
No. It is currently night time in Brazil so it runs at 0%. It may run at 80% power for an hour on a sunny summer day. This isn’t pedantism. The capacity factor isn’t even mentioned in the article.
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Post by cyrilr on Nov 4, 2023 19:23:43 GMT 9.5
And I should point out that the 9000 EUR/kWe is being paid for by the taxpayer; the Dutch grid infrastructure company, Tennet, is state owned.
So that's a 9000 EUR/kWe subsidy. Hiding in plain sight.
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Post by cyrilr on Nov 4, 2023 19:20:35 GMT 9.5
I wouldn't say the unreliables issues are "out of the way". There is current not a single country being powered by wind and sun. This after trillions in "investment" (renewables people often have difficulty underestanding the difference between investing and spending). For example be sure to read Jack Devanney's work on making wind and solar work for Germany. gordianknotbook.com/download/nuclear-and-dunkelflauten/That is one heck of a lot of overbuilding. That means much more steel, concrete and land used, and wasted power. Isn't going green supposed to reduce our footprint and reduce waste? Seems like a wind and solar powered grid would would embrace waste and excessive resource consumption. That includes critical metals - copper, rare earths, you name it. Devanney's work doesn't even include grid costs. Here in Holland we are going to spend 90 billion euros to connect 21 GWp of offshore power. Which is at most 10 GW average power. That's 9000 EUR/kWe just to plug the pinwheels in. And by the time all the infrastructure is in place, the wind turbines will be at the end of life and turned to scrap. How is this fixed in terms of economics and ecologics?
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Post by cyrilr on Nov 4, 2023 19:11:30 GMT 9.5
Low carbon bitumen? That like dry water? Stuff is about as high carbon as it gets.
It is largely used because it is a waste product from oil refining. Not much value. So it is cheap.
It isn't that great, especially in hot climates it crumples up from the heat and contributes to the heat island effect.
Concrete does fine. It is made from natural abundant materials. Limestone, sand and gravel. Won't be running out of those any millenium soon. You just have to find a clean substitute for the heat energy required to make cement and the rebar steel. That is done today with natural gas and coal. It could be done with biogas, hydrogen, high temp nuclear heat. It would be nice to have a lower energy intensity alternative to the rebar steel. Basalt fiber is interesting.
There is also some promising work going on for making clean iron using aqeous electrolysis. Being a low temperature process it uses less energy, and using electricity means all you need is a clean source of electricity, which is much easier than getting "clean coal" for cokes.
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Post by cyrilr on Nov 4, 2023 2:42:31 GMT 9.5
Some funky company claiming to have a great idea in high temperature thermal storage. silbat.com/The big idea being to melt silicon metal for energy storage and recover it via thermophotovoltaics. This doesn't make much sense to me. According to this: www.nature.com/articles/s41586-022-04473-yTPV at the relevant temperature has an efficiency of around 1/3. So 3 kWh in and only 1 kWh comes out. That's terrible. Perhaps for a small application, the use of TPV would make sense, but for a large application it is obvious that a combined cycle gas turbine of sorts would produce much better efficiency. Heck you can get 50% efficiency with a state of the art steam turbine single cycle. Further, silicon metal is quite expensive. It would be better to use something cheaper like steel or cast iron. Steel melts at around 1500C. Ledeburite (cast iron eutectic) has a melting point of 1147C for something a bit less spicy; HX tubes will be required for the metal bath. SiC-SiC is probably a good option. With a combined cycle it could probably run around the 60% efficiency mark. Which isn't super great but it may pass as cheap energy storage.
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Post by cyrilr on Nov 3, 2023 1:29:43 GMT 9.5
So 6 years time to build 10000 GW of wind and solar, connect to the grid (no cost mentioned for this) and somehow prevent grids from collapsing without dramatic curtailment. Renewables people are smoking strong stuff. Unfortunately these junkies are in charge.
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Post by cyrilr on Nov 3, 2023 0:17:22 GMT 9.5
Yes, sorry, I tend to lump in all cracking as FCC, but that's not really accurate, as hydrogen demand for hydrocracking is actually quite big.
Not entirely sure why hydrocracking for gasoline isn't more popular. You'd need more hydrogen for it compared to kerosine, but other than that I can't think of a technical reason it isn't done?
Once we have high temperature nuclear reactors commonly available, the hydrocracking route becomes much more attractive, since the added hydrogen energy is clean. Flying on hydrocracked kerosine would then become partly flying on nuclear power.
I'm not as sanguine about near term reductions of petroleum demand. Gasoline is probably the one big guy to drop, with electric and hybrid vehicles taking over the world by storm. But diesel is much harder to replace, being used mostly for large machinery and long haul transport, which are tough to provide with batteries. And bunker oil for shipping is even harder to do with batteries. Natural gas could take over a lot of these markets though, in which case there'd be a big drop in oil demand for these. Plastics are tough to replace, there isn't enough biomass to make all PE and PP and so on sustainably.
The only realistic near term alternative to shipping, aviation and long haul road transport is natural gas, mostly as LNG for transport and low pressure NG for plastics production. Along with the need for large amounts of natural gas to balance out wind and solar heavy grids, it means that natural gas is the quiet winner in all this. This is what I would expect to play out over the coming decades. Gasoline demand plummets from electric vehicles, with heavier fractions and plastics increasingly replaced with natural gas. It'll be interesting to see how the refiners would respond to this. Natural gas needs little refining.
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Post by cyrilr on Oct 30, 2023 18:05:04 GMT 9.5
From a refining viewpoint this isn’t a big problem, with the advent of fluid catalytic cracking.
From a sustainability viewpoint it is more difficult. In the near term some green hydrogen could be produced and used to upgrade oil, effectively flying on clean hydrogen, at least on the margin.
Longer term high temp nuclear reactors can make synfuel. I think hydrogen is too heroic for aviation, heck even Musk thinks we should use methane for rockets.
Really longer term, batteries could get good enough for longer and longer flights. Boeing had a great stepping stone approach with the development of 4 engined aircraft with one engine electric, presumably moving to more engines electric over time. Sadly they cancelled the project.
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Post by cyrilr on Oct 25, 2023 17:02:54 GMT 9.5
5% loss in 1000h. So most of its power output will be gone in a year or two. Not exactly “solving the stability problem”.
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Post by cyrilr on Oct 15, 2023 19:17:03 GMT 9.5
Condensation isn’t a problem; the problem is rather if you don’t condense it. Exhaust T for gas turbines is very high. No condensation. But, a lot of energy is wasted. Much more so than with natural gas. You want a condensing application when firing hydrogen, so the heat can be recovered. A CCGT or cogen process heat with flue gas exit << 100C. Fortunately, condensing clean water vapor is very easy; with no sulpheric or carbonic acid around, corrosion is not much concern, allowing cheap materials. Hot water production is potentially interesting. You could store hot water in a pit thermal store which is ridiculously cheap.
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Post by cyrilr on Oct 14, 2023 22:47:30 GMT 9.5
Article about using flooded old coal mines as a hot water source. www.euronews.com/green/2023/10/14/flooded-and-forgotten-how-europe-s-disused-coal-mines-could-help-heat-our-homesArticle seems a bit over optimistic and doesn't provide perspective. For example, the claim of 2 billion m3 of hot water seems big, but is actually quite modest. 2 billion m3 * 4.18 MJ/K * 20K dT = 167.2 billion MJ. That's equivalent to less than 5 billion m3 of natural gas. With 28 million households in the UK, even with very good insulation (say average of 1000 m3/year/house) this will heat the UK's households for 2 months. Not exactly sustainable!
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Post by cyrilr on Oct 11, 2023 3:43:38 GMT 9.5
Respect for those truck drivers!
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Post by cyrilr on Oct 3, 2023 18:39:29 GMT 9.5
www.scientificamerican.com/article/worlds-largest-fusion-project-is-in-big-trouble-new-documents-reveal/A bunch of theoretical physicists trying to build a real reactor. Zero manufacturing tolerances on massive components. Oblivious to the well known problem of stress corrosion in welded stainless steel. Moving the goalpost as you go along burning taxpayers money. Constantly reinventing the wheel rather than buying off the shelf components. The politicial differences and legal framework problems from many different countries working together. Zero tolerance for risk. An impractical overly complex reactor architecture. And even if it works it won’t generate any electricity - an even bigger and more complicated successor reactor will be required for that. What could possibly go wrong with that?
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Post by cyrilr on Oct 2, 2023 23:00:48 GMT 9.5
10 years ago they said they would have a 50 MW prototype in 2019. I critiqued them on many points. Now in 2023 they have 0 MW. Now they get 500 million in funding. Some of my criticisms: - no discussion of radiation damage to all the solid state electronics, which are wrapped right around the active core of a fusion reactor - no discussion of plasma stabilities for 1 Hz pulsed operation over many months, years (not demonstrated) - 1 Hz likely not enough - this is like a diesel engine, probably needs to be at least 10 Hz for reasonable power densities. - no discussion on wall damage - not demonstrated since they have not generated meaningful kWhs. - no discussion on electrical conversion efficiency - sure you could generate "some" electricity inductively, but most of it? Really? The claim seems to be 95%. That's implying the plasma temperature is dropped from say 100 million K to 5 million K, before losses? - the usual talk about how it fits in a shipping container. Come on! The radiation shields alone won't fit in a shipping container. Probably needs around 3 meters of concrete bioshielding. Maybe if they bury or mound the container in 5 meters of dirt it’d be ok. - aneutronic fusion - aneutronic my butt. He3 fusion is very roughly about as aneutronic as a fission reactor in terms of neutron energy yield per kWh. And the netrons are very energetic. And that's just the start of my list...
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Post by cyrilr on Sept 22, 2023 21:28:34 GMT 9.5
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Post by cyrilr on Sept 19, 2023 20:30:56 GMT 9.5
But from the linked article the Singaporese want this and more. They’re rich. Rich people do all manner of silly things and want even more silly things. Things that are not of much consequence on global primary energy supplies, or of use to the world’s poor.
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Post by cyrilr on Sept 19, 2023 0:43:41 GMT 9.5
What a silly idea. You don't put in 4000 km cables unless all other options are exhausted.
Singapore has good sunshine year round, and could easily generate solar power itself, by means of floating PV plants. Or get it from Malaysia or Indonesia.
And an even better plan would be for Singapore to purchase several Thorcon Isles. They can be moored offshore if no near shore space is available.
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Post by cyrilr on Aug 30, 2023 2:15:29 GMT 9.5
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Post by cyrilr on Aug 30, 2023 2:01:10 GMT 9.5
I looked at using GE7FB gas turbine to see how many stages would be needed.
We'll need 5 stages of compressors and expanders.
Ballpark figures. After each stage of compressor there would be a plate HX to cool the air temperature from 100C to 20C. Cooling is regenerative to the water pond, which is heated from 15C to 95C.
Likewise the 5 stages of expanders would first take the hot water to heat the air back up to 90C, before it is expanded to 10C.
actual temperatures would be a few degrees off as air heat capacity increases slightly towards the 18 bar operating pressure and there'd be slight pressure loss in the HXs. Plus there'd be more loss on the inlet/outlet. On the other hand the efficiency of the turbines and expanders is better with smaller pressure ratios.
Higher pressure would just mean more stages and HXs. A single thermal store can be used.
Someone needs to run a gatecycle model or some such to check this further. It seems quite promising.
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Post by cyrilr on Aug 22, 2023 4:43:41 GMT 9.5
I could do this all day but honestly I'm not being paid for this and half way into the "study" it is so apparent that this is a dog turd that it is a waste of time (and hand-soap) to dig any deeper.
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Post by cyrilr on Aug 22, 2023 4:39:36 GMT 9.5
Oh more lovely quotes from this lovely "study":
"We interpret the P value as a continuous measure rather than limiting interpretation to dichotomisation of the P value at a threshold for declaring significance (such as 0.05). We fitted models by using conditional Poisson regression with primary control for confounding obtained by stratification, implemented in the SAS software package (version 9.4)"
Translation: we have a bogus study with a bogus criterion, but by using statistical word salads, we divert your attention from this. Also we have an overpriced commercial software to asses our bogus dataset and bogus criterion so we sound awesome and no one will question that we are polishing a turd with diamond powder.
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Post by cyrilr on Aug 22, 2023 4:37:55 GMT 9.5
More quotes:
"We report likelihood based 90% confidence intervals for estimates of the excess relative rate per Gy, a common approach in radiation epidemiological studies in which the objective is to evaluate whether an increased risk of cancer exists after exposure to radiation; this facilitates comparison of the precision of our estimated associations with findings reported in other important epidemiological studies of populations exposed to radiation."
Translation: other studies didn't look at dose rate, and they got paid, so we can't be bothered either.
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Post by cyrilr on Aug 22, 2023 4:34:48 GMT 9.5
More lovely quotes:
"We derived an estimate of between country heterogeneity in association by using the method of DerSimonian and Laird for random effects"
Translation: since our study is bogus, the results didn't make sense and weren't comparable between countries, so we made it believable by using someone else's arbitrary botch method to make it look credible and pretend the countries are all comparable. No one will notice because no one will bother to check out a boring reference anyway.
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Post by cyrilr on Aug 22, 2023 4:30:27 GMT 9.5
Boy this stuff really shouldn't be reviewed when sober:
"cumulative doses were restricted to the lower dose range, workers with a positive neutron dose were excluded, workers flagged for internal contamination or monitoring were excluded, and regression model adjustment was made for workers flagged for internal contamination or monitoring. We compared results obtained under alternative lags with respect to goodness of model fit"
Translation: we only looked at the worst signal to noise ratio cohort, we didn't include a bunch of stuff that may be relevant but we didn't like for unexplained reasons, and then we fitted that to our bogus math salad model. Then we compared the bogus results using an arbitrary statistical method for models that has no bearing on whether the model is good or bad.
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