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On other order of things, I must said that I knew personally met Pedro Prieto in my youth.
Remember when I told in the other thread about my past as former peakoiler?
Well... He was one of the most important voices of the peakoiler movement in Spain.
https://www.15-15-15.org/webzine/es/author/ppp/
Besides, the numbers are based on old data.
https://www.semanticscholar.org/paper/S … fbc2dbef9a
Calculating the Energy Return on Energy Invested (EROI) for Spain's Solar Photovoltaic Energy in 2008
His numbers are always like that. He always took the worst possible numbers. And when even with that it wasn't enough to met the value he want, then he changed the methodology.
Instead of a classic EROEI as it was more common in oil, he did a "new concept" (I don't remember if he was the first, but the first time I met that was through his work), something that they named "EXTENDED EROEI".
That concept is non serious. It's based in add a lot of energy to the input under the excuse that "it's needed" with doubtful formulas to convert that concepts into energy.
I read forward "calculations" about this new EROI and it was coming more and more ridiculous. Adding costs like labor costs to energy (that energy is what we use with the output energy, it's never accounted as an input in other energy), stealing (if they steal the panels, the panels are working in another place. That's not an energy concept, but a business one), even roads! (man... the roads are not only used for installing PV, you can't account that energy as it was done exclusively for photovoltaics).
This is not the first time there is a fight among the numbers.
Here you have an example.
This is a response against a similar study that used the methodology that I was referring.
https://www.nrel.gov/docs/fy17osti/67901.pdf
Inappropriate comparisons of results from their ‘extended’ system
boundary analysis to those of other differently bounded analyses of
conventional energy systems;
• Utilization of incorrect data (either because it is out-date or simply
wrong) for determination of PV system parameters (including
annual electricity yield)
• Several incidents of double-counting energy contributions (e.g.,
adding contributions that are already included in the embodied
energy of materials).
Our revised EROI and EROI EXT values for PV systems in
Switzerland, 3 calculated according to the formula adopted by Ferroni
and Hopkirk (i.e., as the ratio of the total electrical output to the
‘equivalent electrical energy’ investment), but based on the arguments
and numbers presented in this paper are, respectively, EROI≈9–10
(when adhering to widely adopted ‘conventional’ system boundaries as
recommended by the IEA (Raugei et al., 2016)) and EROI EXT≈7–8
(when instead adopting ‘extended’ system boundaries that also include
the energy investments for service inputs such as ‘project management’
and insurance). It is especially noteworthy that even the latter EROI EXT
range is one order of magnitude higher than 0.8 which was obtained by
Ferroni and Hopkirk.
This is a response to another work, here from "Ferroni and Hopkirk" that reached even lower EROEI.
I can't quote the original Prieto & Hall work, because it's paid. But I can say you that the original data it was quoted, 2008, the prices has already dropped by more than one order of magnitude since then.
There were a lot of critics about that 2008 bubble in Spain. But by then it wasn't rare that the government paid up to 300€ per Mwh on subsides. Now they are installing PV without any subsides with an estimated LCOE under 30 €/Mwh.
EROEI numbers become unusable long ago when different sources obtain so different numbers.
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So you are accounting 212 kg per kw.
But 1 kw of PV are aprox. just 3 standard 60 cell panels of 18 kg per unit. A total of 54 kg.
Even if you argued that the panels aren't the total weight of a PV installation, to multiply that number by 4, a lot of inefficient things are being done to reach that values.
No, not really. All you have to do is assume a capacity factor of 25%. Which for solar would be a really good capacity factor; in Britain it's more like 10% (but we're not exactly the sort of place you'd put solar if you were thinking straight).
"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony
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Spaniard,
216*24*365*0,2*20 = 7.568.640 twh
Total global annual electric power consumption is 25,000TWh.
7,568,640TWh / 25 years = 302,745.6TWh per year <- This is 12X total global annual demand for electricity over 25 years
Your math is wrong. Try again.
Edit: If all we needed to do was to make 216GW of installed PV capacity, and that would provide all of humanity's energy needs many times over, then we wouldn't be having this argument. I would simply have accepted that the change already happened. I think this is what's wrong with the world today. Ideology / belief / want has overridden reason. 8,820TWh is pretty close to the actual 2023 electrical power generation figure for China, an average of around 735TWh per month.
Edit #2: The reason I label all my figures is first for my own understanding of what I'm calculating, and second, so that everyone else can see what the figures I used actually represent. I can infer the following from the numbers you used:
216 number of GigaWatts of installed solar electric generating capacity
24 hours per day (When did photovoltaics start producing electricity at night?)
365 days per year
0,2 or 20% total efficiency for the photovoltaic panels and electric power plant
20 years of commercial electric power generating operations
If you're going to throw numbers at us, please label them so that someone besides yourself knows what you're actually referring to. I can follow or infer what you did there, but others may not be able to. Regardless, your figures are off by a factor of 1,000 (GWh vs TWh), so the total power output figure is 7,568.64TWh of power over 20 years, if photovoltaics could actually produce power for 24 hours per day, which they cannot.
For a desert environment, accounting for no Sun tracking or single-axis Sun tracking, I assume 5 hours per day at the photovoltaic panel's maximum rated output per unit area, because you have 4 hours of prime power output, plus a much lower output since all the rest of the power output occurs while the Sun is lower on the horizon, so that power can be expected to add up to about 1 additional hour at full rated output, in terms of total Watt-hours of power generated. Alternatively, you can use 5 hours per day * 365 days per year = 1,825hrs of prime power output provided per year. There are 8,760 hours per year, so this is 20.833% of each year. In reality, any non-desert locale or latitude far above the equator will produce rated power 10% to 15% of the time. 11% is an approximate global average for all photovoltaic power installations.
Last edited by kbd512 (2024-03-31 11:48:38)
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Spaniard,
Spaniard wrote:216*24*365*0,2*20 = 7.568.640 twh
Total global annual electric power consumption is 25,000TWh.
7,568,640TWh / 25 years = 302,745.6TWh <- This is 12X total global annual demand for electricity over 25 years
Your math is wrong. Try again.
That unit is gwh, not twh. But it's just there where I put the wrong unit. As you can see later, when I divided by 4 using EROEI to calculate what it was supposed to be spent under that numbers, I write gwh.
I will edit the post now.
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In fact, I used your numbers and the result is even more extreme. Look.
Tons Mwh per ton Mwh Percentage
Glass 70000 9,7 679000 3,79%
Steel 56000 13,9 778400 4,34%
Concrete 47000 6,96 327120 1,83%
Aluminum 19000 64 1216000 6,79%
Silicon 7000 2100 14700000 82,05%
Copper 7000 16,2 113400 0,63%
Plastic 6000 17 102000 0,57%
Total= 17915920 * 320 = 5.733.094.400 MwhUsing your numbers, I obtain 5.733.094 Gwh which is even more extreme than what I said.
Although if you see the numbers with care you will notice that mods energy come from silicon.
That was usually the thing in the past. Everybody that knows a little about the PV industry knows that the PV cells are the most expensive part of the whole infrastructure, and the piece that has become cheaper in these years.
---
I have edited to add the percentage.
Last edited by Spaniard (2024-03-31 11:56:39)
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So you are accounting 212 kg per kw.
But 1 kw of PV are aprox. just 3 standard 60 cell panels of 18 kg per unit. A total of 54 kg.
Even if you argued that the panels aren't the total weight of a PV installation, to multiply that number by 4, a lot of inefficient things are being done to reach that values.No, not really. All you have to do is assume a capacity factor of 25%. Which for solar would be a really good capacity factor; in Britain it's more like 10% (but we're not exactly the sort of place you'd put solar if you were thinking straight).
I was comparing two different sources of data. The weight from current PV specifications and kbd512 data both for materials used in a certain power of PV.
So here it has no sense to speak about capacity factors. Unless you are suggesting that kbd512 data are not for 1 GW PV for real, but 1GW equivalence of 100% capacity factor.
That argument would turn in favor of my argument. But I don't think it's the reason of our discrepancy.
The most probable reason is that the numbers are not PV generic, but for installations on ground (otherwise they aren't concrete, or it's averaged the numbers would be lowered significantly), AND the numbers come from outdated technology. That would explain why the numbers of glass weight are higher than current standards.
PV panels hasn't become cheaper for nothing. The energy involved in the process has to become a lot less too.
Last edited by Spaniard (2024-03-31 11:55:09)
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Spaniard,
In fact, I used your numbers and the result is even more extreme. Look.
Tons Mwh per ton Mwh Glass 70000 9,7 679000 Steel 56000 13,9 778400 Concrete 47000 6,96 327120 Aluminum 19000 64 1216000 Silicon 7000 2100 14700000 Copper 7000 16,2 113400 Plastic 6000 17 102000 Total= 17915920 320 5.733.094.400Using your numbers, I obtain 5.733.094 Gwh which is even more extreme than what I said.
Although if you see the numbers with care you will notice that mods energy come from silicon.
That was usually the thing in the past. Everybody that knows a little about the PV industry knows that the PV cells are the most expensive part of the whole infrastructure, and the piece that has become cheaper in these years.
We've become much more efficient at manufacturing photovoltaics, but to my knowledge there's a thermodynamic minimum energy to melt Silicon, or any other metal for that matter.
2,100GWh of embodied energy per 1,000t of Silicon for 1GW of photovoltaic generating capacity * 216GW desired installed capacity = 453,600GWh = 453,600,000,000,000Wh of embodied energy
453,600,000,000,000Wh / 8,141Wh per 1kg of coal = 55,717,970,765kg of coal 55,717,971t of coal
China's 2023 coal output hits record high
BEIJING, Jan 17 (Reuters) - China's coal output reached a record high in 2023, data from the statistics bureau showed on Wednesday, amid an ongoing focus on energy security and a rise in demand after pandemic-related restrictions eased.
The world's biggest coal producer mined 4.66 billion metric tons of the fuel last year, up 2.9% from a year earlier, according to the National Bureau of Statistics.
For December, output reached 414.31 million tons, nearly flat with November's 414 million tons and up 1.9% from the year-earlier level.
Daily output over the month was 13.36 million tons, slipping from November's record high daily average of 13.8 million tons.
The country's overall power generation, which is dominated by coal-fired plants, rose 8% year-on-year in December.
Analysts are predicting another modest coal production increase in 2024. The rate of growth has slowed over the past year, following an energy security push that drove a ramp-up of output beginning in 2021.
In 2023, domestic production growth was "roughly flat, largely due to safety-related mining suspensions", analysts at Macquarie wrote in a note, resulting in demand growth outpacing supply growth.
That pushed China's coal imports higher, to a record high of 474.42 million tons in 2023, the customs administration said last week, as users turned to imports due to rising prices and diminished quality of domestic coal.
Your favorite energy generating technology is a monument to coal production. Nothing more.
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The difficulty with EROEI calculations, is always where to set system boundaries. It is entirely reasonable to factor things like roads into EROEI calculations, if they were built specifically for the powerplant or if the presence of the powerplant increases maintenance burden in a way that can be quantified. It is also quite reasonable to factor labour into EROI calculations. Labour is a resource after all. People paid to do a job are giving up time to do it and are paid in money which is used to buy energy products.
Besides, the numbers are based on old data.
https://www.semanticscholar.org/paper/S … fbc2dbef9a
Calculating the Energy Return on Energy Invested (EROI) for Spain's Solar Photovoltaic Energy in 2008
His numbers are always like that. He always took the worst possible numbers. And when even with that it wasn't enough to met the value he want, then he changed the methodology.
I don't think 2008 really counts as 'old data'. What has changed since then is supply chains shifting overwhelmingly to China. The Chinese have surprisingly rational reasons for doing this. Coal production in their industrial heartlands is declining. Overall coal production is still increasing, but all of those increases are from outer provinces away from the population centres.
https://www.iea.org/data-and-statistics … -2018-2019
It is impractical to ship coal over distances of hundreds of km over land. So the Chinese use forced labour in their Islamic fringe provinces to mine coal and supply coal burning powerplants at the minehead. This produces some of the cheapest electricity in the world. Xinjiang is a good case in point. It is where about 90% of the worlds polysilicon is refined. By making solar power infrastructure that can be shipped by rail, the Chinese are able to store coal energy in solar infrastructure, which is far more compact and transportable than the coal used to make it. By installing this infrastructure in their core provinces, coal burning plants can be used as backup stretching the benefits of a reduced coal supply. It has kept the lights on in China and has reduced the cost of solar infrastructure to low levels. But don't be fooled. This infrastructure is stored coal energy produced using slave labour. EROEI doesn't factor into cost directly, because the coal used woukd otherwise not be mined and the labour costs are extremely low. But costs can only remain low so long as these inhumane practices continue.
Our revised EROI and EROI EXT values for PV systems in
Switzerland, 3 calculated according to the formula adopted by Ferroni
and Hopkirk (i.e., as the ratio of the total electrical output to the
‘equivalent electrical energy’ investment), but based on the arguments
and numbers presented in this paper are, respectively, EROI≈9–10
(when adhering to widely adopted ‘conventional’ system boundaries as
recommended by the IEA (Raugei et al., 2016)) and EROI EXT≈7–8
(when instead adopting ‘extended’ system boundaries that also include
the energy investments for service inputs such as ‘project management’
and insurance). It is especially noteworthy that even the latter EROI EXT
range is one order of magnitude higher than 0.8 which was obtained by
Ferroni and Hopkirk.
Hall is the originator of the EROEI concept and has spent decades refining the methodology. But the concept has been used by a lot of analysts who give different results depending on the assumptions used in the study. One fiddle that is often employed when calculating the EROEI of a wind or solar powerplant, is to assume that every kWh of electricity produced displaces 2-3kWh of fuel burned in a fossil fuelled powerplant. They then count the avoided fuel consumption as the energy output, which inflates EROEI by a factor of 2- 3. Another common trick is to ignore ancillory energy costs like backup, storage and transmission, even though they are integral parts of the ekectricity supply system.
Last edited by Calliban (2024-03-31 15:13:43)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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I haven't been following this thread closely and maybe I'm missing something but I notice kbd512 cities 2,100 GWh per 1000T of silicon, which reduces down to 2.1MWh per kg. 1 MWh is one million watts for 1 hour (3600 seconds)—3.6 GJ. So the number being cited is that producing Silicon for PV cells consumes a bit more than 7.5 GJ/kg of silicon. As a gut check, the Gibbs free energy of SiO2 is -856.4 kJ/mol, which is about 30.6 MJ/kg of Silicon. The claim is therefore that the total process efficiency for SiO2 -> Si is about 0.4%. I find this extremely dubious. Is it possible an error was made?
Last edited by JoshNH4H (2024-03-31 15:12:03)
-Josh
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JoshNH4H,
How much energy does it take (on average) to produce 1 kilogram of the following materials?
Electronic grade silicon (CVD process): 7,590-7,755MJ (2,108,700 to 2,154,900 watt-hours)
Maybe they're using a different grade of Silicon for photovoltaics and never have to reject any of the Silicon produced. I certainly hope so.
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I haven't been following this thread closely and maybe I'm missing something but I notice kbd512 cities 2,100 GWh per 1000T of silicon, which reduces down to 2.1MWh per kg. 1 MWh is one million watts for 1 hour (3600 seconds)—3.6 GJ. So the number being cited is that producing Silicon for PV cells consumes a bit more than 7.5 GJ/kg of silicon. As a gut check, the Gibbs free energy of SiO2 is -856.4 kJ/mol, which is about 30.6 MJ/kg of Silicon. The claim is therefore that the total process efficiency for SiO2 -> Si is about 0.4%. I find this extremely dubious. Is it possible an error was made?
Semiconductor grade silicon is one of the most energy intensive materials used by man. It requires impurity levels not exceeding 1ppb. That is extremely energy intensive to achieve and is reflected in the high cost of semiconductor grade silicon, being 10x greater than metallurgical grade.
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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JoshNH4H,
Carbon emission analysis of two crystalline silicon components throughout the life cycle
3.1.1. Industrial silicon production. According to “The norm of energy consumption per unit products of silicon metal” (GB31338-2014), the limit of comprehensive energy consumption of existing industrial silicon production units shall be not more than 3500 kgce·t-1 (kg standard coal·t-1). The comprehensive energy consumption limit of new industrial silicon enterprise shall be not more than 2800 kgce·t-1. The advanced comprehensive energy consumption limit of industrial silicon enterprises shall be not more than 2500 kgce·t-1. According to Zhang Huayu investigating 11 industrial silicon enterprises in Xinjiang in 2019, the results show that the average industrial silicon energy consumption per unit product is 719.18 kg standard coal / ton higher than the domestic advanced value, while Xinjiang industrial silicon output ranks first in China, accounting for more than 40% of the national total output [12]. Therefore, the comprehensive energy consumption of industrial silicon is 3219.18 kgce·t-1. According to the energy conversion factor of 8.137 kWh·kgce-1 [13], unit carbon dioxide emission is about 577 g·kWh-1 [14], the comprehensive energy consumption of industrial silicon production stage is 26194.47 kWh·t-1, industrial silicon production stage is 15114 kgCO2-eq·t-1.
3.1.2. Purification of solar-grade crystalline silicon. The polysilicon purification process is mainly the improved Siemens method and the silane fluidized bed method [7]. The rod silicon produced by the modified Siemens method accounts for more than 97% of the national total output. Therefore, this study takes the modified Siemens method as an example. According to “Prediction of Key Technical Indicators of polysilicon link in China” released by China Photovoltaic Industry Association and GB 29447-2012 “The norm of energy consumption per unit products of polysilicon enterprises”, 2020 annual comprehensive energy consumption of polysilicon is 11.5 kgce·kg-Si-1, electrical consumption is 93.58 kWh·kg-Si-1. Therefore, the carbon emissions in the solar-grade crystalline silicon purification stage is 54 kgCO2-eq·kg-Si-1.
26.194kWh/kg sounds more reasonable, but it's also 3X higher than Gibbs free energy. I hope this is what we're actually looking at in terms of energy input.
Silicon is found in nature in the form of silicon dioxide (like some types of sand and many rocks). The extraction of silicon from silicon dioxide is extremely energy intensive; it requires 1000-1500 megajoules of primary energy per kilogram to process high-grade silicon for computer chips or solar panels.
This seems much more reasonable, but does it also include rejection?
How much of the Silicon becomes kerf to produce wafers of a given size?
They do cut the metal to produce square Silicon wafers for photovoltaic cells from round bars / ingots, so some of that metal never produces any power, but must be created from SiO2 anyway, in order to be cut into shape, which means that even if the end product only contains 1kg off Silicon, then surely some amount of Silicon in excess of the 1kg that becomes a photovoltaic cell was required to produce the wafers to begin with. Perhaps that's where the 7,590MJ/kg figure actually comes from. I would imagine that imperfect ingots or kerf are then remelted into new Silicon bars / ingots, so some considerable amount of energy is required to remelt that material, since it melts at 1,414C.
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Hey kbd512,
3x gibbs free energy strikes me as an entirely plausible number and I appreciate that you took the time to track it down. The paper implies that they're doing a truly full accounting, looking at all the energy inputs and also at the actual modules you're getting out. That paper is also the most recent and the most direct. As you and others have pointed out the embodied energy in the panels is a key factor determining if they're going to be a feasible energy source, so I have no doubt that they're working hard to make it better all the time. The paper discusses this and finds that they are. So I do think that ~100 MJ/kg is the number we care about, accounting for the various losses.
Further down they estimate that the energy payback time for solar modules, getting a number around 13-14 months. With panel lifetimes in the range of 10-20 years, this gives a pretty good EROI, and given the competitiveness and low margins of the solar manufacturing industry I'd expect that energy payback time to keep creeping down and lifetimes to creep up. Having said that, it wouldn't surprise me if in the long term PV panel production locates itself in places where solar energy is most plentiful--The American Southwest, North Africa, the Australian outback, South American deserts, Western China, etc. The panels will be in effect a kind of energy export to less sunny locales.
In the longer long term we may find that orbital space, with no weather and no day-night cycle, has the best competitive advantage here, and so Earth is importing solar panels made from lunar materials with energy produced in L4/5. Cheap energy (downstream of strong sunlight, provided we can actually produce the panels cheaply in space) will be an incredible pull for locating industry offworld, though the limited labor pool and vacuum/zero g will slow that shift down.
Last edited by JoshNH4H (2024-03-31 18:45:28)
-Josh
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JoshNH4H,
That's the energy to make the metal, which is a relief because I was trying to figure out how they were consuming so much energy just to make a semiconductor substrate, but I don't know if that paper truly shows us what we want to see (reduced energy consumption), because it's fixating on CO2 per unit of product, and that is key. From the CO2 emissions, we can make some generalizations about the energy involved since it specifically mentions the use of coal.
I found a reference in an electronics / computer magazine indicating that it takes 7,560MJ of energy to make 1kg of microchips, so I'm no longer as concerned that the energy figure quoted for the Silicon in Low-Tech Magazine is just to make the metal, because that's a crazy amount of energy.
1kWp = 70.9649028g of Silicon wafer, because 16.13g/m^2, and 1.98m^2 450Wp implies that much Silicon for a "1kWp"
From the paper on Chinese Silicon production:
Therefore, this article cites the data released by the New Energy Chamber of Commerce of the All-China Federation of Industry and Commerce, and the converted carbon emission of crystal silicon components production is 133.62 kg·kWp.
CO2 emissions from the most environmental-friendly energy sources, solar, and wind, emit around 4-6 g CO2/kWh. The CO2 emissions from coal as an energy source are 109 g CO2/kWh. (CarbonBrief) These are all still significantly lower than the estimated emissions from a diesel generator: 1,27 kg CO2/kWh.
133.62kg of CO2 / 0.109g of CO2 per kWh of energy produced = 1,225,872Wh (4,413MJ) per 1kW photovoltaic panel (which doesn't contain 1kg of Silicon metal, nor anything close to it)
CO2 emissions typically imply burning something, so I'm guessing that something is coal-based electricity or Carbon in the furnace itself.
Carbon emissions generated by transporting 100 kg of components to 150 km are about 2 kg. Therefore, CO2 emissions of the component installation and transportation process are 207.72kgCO2·kWp
A modern diesel semi-truck emits about 0.074kg of CO2 per MJ of energy converted, which implies 2,807MJ of energy input was expended to drive the panels from the factory to a nearby locale, and to actually set them up to generate power, so 7,220MJ to make a 1kWp array, transport it a short distance, and then set it up to generate electrical power.
I would wager that there's more diesel consumption to ship the product half-way around the world. The point is, the energy input into these panels is astronomical, relative to what they are and how long they'll last in normal operation.
There are more CO2 emissions listed further into the document for panel recycling, which implies more energy input for a system that is truly sustainable.
I really want this to work, but the EROEI is marginal unless the panel is located in an ideal spot on Earth, and then it looks like a pretty good deal to me. The problem is that we have people trying to put these things in places that get less than half as much insolation as the Gobi Desert or Arizona. That's where the case looks pretty marginal to me, and here in Houston where we're powered by 100% clean renewable wind turbines according to the nonsense propaganda of our greens, none of the gas turbines have been shut off downtown at any point in time, and I know this because I can smell them when I walk by and feel the heat when the wind blows the exhaust back into the pavement.
All told, solar thermal power looks like a much more sustainable long term prospect for cleaner energy. Recycling happens every 75 years instead of every 25 years, same as any other thermal power plant, and the generator can be a centrally located machine with spinning reserve capacity to gracefully ramp down so that we don't have terawatt-scale power fluctuations when a cloud passes overhead.
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It's definitely true that sunny desert locations are better for solar than cloudy northern locations, both based on higher average energy production and on more predictable energy generation.
As far as EROI specifically, I'm not too worried in that I basically think it comes out in the wash when you're looking at $ cost. The US has both solar tariffs and subsidies. I think on net the subsidies are a little bigger (US domestic solar manufacturing is only about 12% of installs ATM) but not enough to dramatically change the equilibrium either way. Different countries have different subsidies but the growth of solar is pretty consistent globally, especially in the developing world where ten hours of electricity can be a big improvement from zero. Likewise energy markets are global enough that it's also not arbitrage of energy prices between the US and China.
And solar prices just keep falling. So maybe West Texas works now and East Texas is more marginal, and maybe in a couple years that won't be so true (or they'll build out more transmission). My high-level theory of solar vs nuclear is that it's so much faster and cheaper to implement improvements in solar that (with the semiconductor boom happening at the same time) we shouldn't be surprised that it eventually won out. Rates vs levels, exponential improvements, etc.
-Josh
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JoshNH4H,
I found a document on OSTI, dated back to 1977, about the embodied energy into different manufacturing processes to produce Silicon wafers for photovoltaic panels. I looked at one of the then-experimental processes and couldn't help but notice that the embodied energy figure looks remarkably similar to the figures quoted by Silicon wafer manufacturers today. We've improved mass manufacturing of semiconductors since then. The energy required to melt a kilo of ore hasn't changed one iota. The kerf rates are the same. The rejection has undoubtedly improved. The labor is cheaper because it's China. The energy is cheaper because it's coal.
Will solar PV and wind costs finally begin to fall again in 2023 and 2024?
It would be great if prices did fall, but that requires cheap energy. The prices are going up on absolutely everything, and that includes metals and manufactured goods. If prices are actually falling for photovoltaics and wind turbines, then those must be the only manufactured goods for which that statement holds true.
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JoshNH4H,
I found a document on OSTI, dated back to 1977, about the embodied energy into different manufacturing processes to produce Silicon wafers for photovoltaic panels. I looked at one of the then-experimental processes and couldn't help but notice that the embodied energy figure looks remarkably similar to the figures quoted by Silicon wafer manufacturers today. We've improved mass manufacturing of semiconductors since then. The energy required to melt a kilo of ore hasn't changed one iota. The kerf rates are the same. The rejection has undoubtedly improved. The labor is cheaper because it's China. The energy is cheaper because it's coal.
China has used coal since the beggining. And labor costs has only increased there. But PV panels has been reducing their price constantly, with no relevant changes in the mix and increasing labor costs.
That excuse could hear well in people that only thinks that PV has become cheap because they have being outsourced to China, but anyone that could check Chinese numbers knows that it's not right, because that variables has been static or worsening there while costs had plummeted. Not a minor change, but a radical one.
You are getting wrong numbers in some place, because the conclusion doesn't meet the reality. For example, a way where they have optimized in silicon is reducing the weight of the material used for capture. Even if the weight/energy ratio wouldn't change (that I doubt it) if you use less weight because the wafers are a lot thinner, obviously the total energy get reduced by a lot.
Solar panels aren't getting cheaper because labor costs or because they are made from coal as you said. That hasn't changed in China for decades.
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We've become much more efficient at manufacturing photovoltaics, but to my knowledge there's a thermodynamic minimum energy to melt Silicon, or any other metal for that matter.
It's easy to miss important things when you aren't an insider, and an insider only knows in detail about the process he is involved.
For example, of course heat something has a minimum thermodynamic value. That's physics. Still, a manufacture process could need less than that quantity per unit of weight processed for example, when they use heat recovering.
It's a common process in the industry, although still has a margin of improvement. 50-60% energy recovery is not uncommon in high temperature process as energy in so much quantities has a significant impact in the final cost.
That's it, once the process at the high temperature has ended, and the final product is hot, that temperature is exchanged with new input raw material in a continuous process. So you don't need to input the 100% of the heat, but just the part lost in the exchange (it can't be 100% efficient).
While the raw material requires that heat to work, heat recovery lower the input of a continuous process by a significant fraction. The heat exists, just it's not new generated heat but recovered (at least a fraction of that).
--- EDITED ---
I checked multiple sources and I found clear discrepancies about the values. From 10-20% in another sources to 70% in others. It's complicated because they can referring to different things (like overall improvements vs process specific recovering) so take the numbers with a pinch of salt.
Anyway, waste heat recycling & recovery are active fields of energy reductions. Real numbers, as always, are more complex than you can.
Here there is a link that claims a very high value (80% estimated from their proposed method), for example
https://www.sciencedirect.com/science/a … via%3Dihub
Last edited by Spaniard (2024-04-01 03:17:07)
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The difficulty with EROEI calculations, is always where to set system boundaries. It is entirely reasonable to factor things like roads into EROEI calculations, if they were built specifically for the powerplant or if the presence of the powerplant increases maintenance burden in a way that can be quantified. It is also quite reasonable to factor labour into EROI calculations. Labour is a resource after all. People paid to do a job are giving up time to do it and are paid in money which is used to buy energy products.
First... you shouldn't compare values obtained through different methodologies. It's an apple to orange comparison.
Second... How do they know how the roads are using? Did they go one by one installation checking if the road was used exclusively to that renewable installation?
Of course not. They will just get some generation places as a template, get the costs of the project, doing "conservative" assumptions and extrapolate to the whole infrastructure.
These "refinements" are not that. They are just numbers adding to the input to obtain the EROEI that they want. That's the reason they change the methodology constantly and the reason they insist in almost fixed EROEI values with a clear pattern of lowering costs in the real world.
Labor costs weren't ever accounted in classic EROEI calculation. The reason is simple. People need very little input. The salary is unconnected with the human needs to make the work there.
Computing salaries has sense in a cost model like LCOE, and of course it's computed. Not only for renewable, but every source of energy.
But in terms of energy, what sense it has you said that in a poor country they uses X energy and in other a total different value just because they paid differently. How that change the energy involved in the installation?
The purpose of energy installations is to generate energy for the society. And workers are just part of that society. If you account the energy for the workers as energy used in the input, you should then remove that energy from the requirements of useful energy needed to generate in the output net energy of the source, that of course, they won't do.
Because of that, count salaries as energy input is double accounting.
Last edited by Spaniard (2024-04-01 01:14:31)
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Spaniard,
If the materials to produce something don't presently exist, and the green energy metals do not presently exist in the quantities required to do what you want done, then that material must be pulled out of the ground and processed into brand new green energy machines. Those processes require enormous amounts of energy, far above what was required with hydrocarbon fuels, so the energy cost of creating these new machines is a non-trivial matter. The present way that is being done is not using solar panels and wind turbines, at all. Whether or not it could theoretically be done using solar panels and wind turbines in the future is a matter of speculation based upon nothing tangible. Non-repeatable green energy stunts don't count as proof that it can be done in a practical way, either. Every single one of these alternative ways of doing things requires a non-trivial increase in metals and energy consumption.
China burns coal to make Silicon, Copper, Lithium, and everything else you think is reducible to some vague generalization about "the future". Last year, they burned 4.66 billion tons of coal. So long as that's how they're operating, and they most certainly are burning fuel to do that, then I think the energy cost of producing what you want is worthy of scrupulous examination.
Hand-waving EROEI is easy to do when you can fall back on coal, gas, and oil. When you cannot do that, if you made any serious miscalculations about how much energy you have to work with, the end result is not a poor economic quarter, it's famine, disease, and death. I do not view any new system that requires complete and radical changes to virtually every aspect of how energy is generated and consumed as something that will be simple, easy, or straightforward. In point of fact, what we should expect is that such changes will take far longer than anyone initially thought, that some ideas will prove completely unworkable at the scale required, and that the path towards something resembling an actual sustainable solution will be anything but a straight line. The repeated attempts to oversimplify, hand-wave, and/or outright ignore the implications is reason enough for concern.
This proposed renewable energy system flirts with energy poverty when it's not intelligently implemented, which directly correlates with actual poverty. There is nothing about the people attempting to implement this system which makes me think they're so enlightened that they're incapable of making consequential and horrific mistakes. COVID immediately comes to mind. I've never seen such an utter failure of reason and prudent action as what most of the western world's medical community inflicted upon the people who they were sworn to "first, do no harm" untoward.
I don't take issue with where my energy comes from. I do take issue with not having the energy people require. I want my own children to retain a quality of life at least as good as the one I've enjoyed over my entire life. That's not an issue that should be hand-waved away with "current trends show", "we'll just substitute materials", or "technology will improve over time". Those explanations aren't arguments in favor of any particular idea, they're dogmatically held beliefs. I trust people who hold beliefs like that, about as much as I trust medical doctors to know how to handle a global pandemic, merely because they have MD next to their name. Having a MD next to their name is a lot less impressive than their ability to rationalize how to best handle an airborne pathogen and mass casualties. I have more than sufficient evidence to illustrate my point about how well that worked out. We had entire cities worth of people who died because we couldn't admit to ourselves that we didn't understand what was happening because we had no experience of it within living memory, and immediately jumping to conclusions was a terrible idea.
We destroyed the global economy, we terrified elderly and infirm people into not visiting their doctors to deal with their existing medical issues, and to top it off we straight-up lied to people about vaccines protecting other people or preventing the spread of COVID. We pathologically refused to accept that certain medications were effective while others weren't, and that mRNA vaccines were highly experimental technology with completely unknown long-term effects. The lack of attention to detail ranged from expensive to tragic.
If we screwed up something as important as life-and-death health care decisions, I will never take as an article of faith that the people promoting these green energy machines have ever thought through all the long term consequences of their actions, because there's precious little evidence that they do any of that. They're utterly fixated on CO2 and cost, except when it runs afoul their beliefs about their favored technology, and then all counter-factuals are ignored or hand-waved as if there's nothing to learn. That's the same sort of thinking that caused the COVID disaster.
What would ease my mind is if I see someone else besides Professor Michaux, who put forth all of their working assumptions about energy sources, materials, and methods, that they bounced their assumptions off of current operative industrial practices, and then came back and said, "yeah, we have enough and we have a realistic plan to do this", or "we need to tweak this part of the plan to get a desirable result", or, as I deeply suspect at this point, "we need a better plan". When I see something like that, I will know that the people who are pushing for this technology have done their due diligence, and aren't operating off of unrealistic assumptions about energy inputs, outputs, and material resource availability. Until then, we have a lot of partially informed speculative beliefs about what the future will look like.
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Spaniard,
If the materials to produce something don't presently exist, and the green energy metals do not presently exist in the quantities required to do what you want done, then that material must be pulled out of the ground and processed into brand new green energy machines. Those processes require enormous amounts of energy, far above what was required with hydrocarbon fuels, so the energy cost of creating these new machines is a non-trivial matter.
You can claim whatever you want. Yes, renewable require a lot of new things. But also fossil fuels require a constant influx of fuel and infrastructure. Nothing new in our way to do things.
Renewable are cheaper, because the total numbers are better than fossil fuels. You can doubt and claim whatever you want. There is no magic involved.
Market does a thousand times better calculation than you can do with lots and lots of studies.
Studies are there (when they are well done) for doing forwards moves and investments. Market tells you CURRENT costs, not future costs, so studies are still important to help us to do future moves.
But things like the plummeting price of renewable in past years it's a FACT. It's already past. And claiming that EROEI hasn't change regardless that fact it's not backed up by reality. And if you search enough you will found more and more discrepancy. The reason is that EROEI is mostly pushed by the people that want to discourage the investment in renewables and the conclusion was decided from the start. That's the reason you can't expect that people to give you good numbers.
Industry and investors are focused on LCOE, because real world move using money, not complex energy formulas. LCOE convince investors, not EROEI.
Still, you will have to search more and more excuses why the supposedly embedded energy in renewables, that low EROEI proponents claim is enormous, has more monetary value than the infrastructure itself. It's like a godly miracle of multiply bread and fish, just with kwh.
Instead of searching excuses like massive subsides, all has a lot more sense when you assume that people that claim higher and growing EROEI on renewables are on the right.
Then, the lower cost has sense. Also continue to investment on renewables, as they will pay their own cost. Renewables moved by renewables. Just we are starting. You can't request to move on renewables TODAY when renewables are still growing and we are still waiting just to reach the point where renewables grow more than the current growth of energy consumption.
Although that moment maybe will be soon enough to the forum to see it. Another thing completely different is to REMOVE all fossil fuels from the mix. I doubt not only the forum, but us will live enough to reach the zero emissions moment.
In any case, invest in renewables is a lot better than do it on fossil fuels. And the people that claim that nuclear is a lot better, only have to invest on nuclear and demonstrate that they can reach better LCOE in real projects.
They won't lack investors if they can back up their claim with real proof.
Last edited by Spaniard (2024-04-01 08:12:03)
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Spaniard,
The prices of metals is going up, not down. Green energy machines require metals. Now that input materials cost is 70% to 80% of the cost of these green energy machines, that means prices will inevitably go up, because that's how market economics works, regardless of any claims to the contrary. Manufacturing and distribution costs for green energy machines could go to zero, but if the price of Lithium, for example, goes up 1,000% in 4 years, then the cost of making any machines using Lithium will inevitably go up.
Renewables are cheaper than having no energy at all, but they are not cheaper than coal, obviously, else China wouldn't still be using any coal to make them. The evidence backing that statement is the number of brand new coal fired power plants being constructed in India, China, and other countries in Asia and Africa.
Prices of renewables haven't been plummeting during the past 4 years. They've been going up. I published a link to an IEA report asserting that renewable prices will go down in 2024, whereas they've gone up for the past 4 years, from 2019 to 2023.
Industry and investors should do a LCOE analysis on renewables without hydrocarbon fuels, because the real world doesn't have a real economy when there is no energy. Renewables without hydrocarbon fuels is practically infinite, because no electric grid can function with photovoltaics when, for example, the Earth rotates and the Sun is no longer providing any input energy, and of course, that only happens once per day.
I've already provided my reasons about the energy embedded into renewables. Physics is going to reassert itself in a way that becomes impossible to ignore when there is no more hydrocarbon fuel energy to dump into this extravagant waste of energy and money.
The issue with cost, which you seem to be working overtime to ignore, is the cost of not having any energy. Renewables without storage are an absolute guarantee of having non-functional electric grids. After we do an LCOE on photovoltaics or wind turbines and batteries or any of the other storage solutions proposed by our green energy fans, you no longer have an argument to make about the cost of renewables being cheaper than the cost of hydrocarbon fuels.
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Spaniard,
The prices of metals is going up, not down. Green energy machines require metals. Now that input materials cost is 70% to 80% of the cost of these green energy machines
All of this projections are based on things you are assuming. There is no need to repeat, we already told our points before (change materials, quality, energy assumption, etc)
Lithium was already double before. Because price is a mix of variables, one compensate others. The reserves had increased because we found new lithium faster than we are currently using it.
There are a bunch of variables to play, and that costs are not as fixed as you said. Otherwise it wouldn't have a reason to coming down again.
Yes... there will be spikes in prices from time to time. Still, as the prices doesn't come as high from raw material as you said, and a lot of players in the market knows possible movements if there is a bottleneck, reacting investing in possible solutions like I mentioned before.
As speaking about the future is cheap, we could continue this loop forever, so as we aren't adding new information, I don't see the point about continue this.
Only we can do is to wait... and this is slow so... stay tuned.
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Prices of renewables haven't been plummeting during the past 4 years. They've been going up. I published a link to an IEA report asserting that renewable prices will go down in 2024, whereas they've gone up for the past 4 years, from 2019 to 2023.
Just a little comment to end. Your own link also said that remain competitive.
What increased was transportation costs... by a lot, which make then more expensive outside of China. BUT it also happened the same for fossil fuels. Most countries also needs to transport fuels. So as expected, impacted more on fossil fuels than renewables, so they remain competitive.
Renewables are cheaper than having no energy at all, but they are not cheaper than coal, obviously, else China wouldn't still be using any coal to make them. The evidence backing that statement is the number of brand new coal fired power plants being constructed in India, China, and other countries in Asia and Africa.
The only reason why China don't replace coal for renewables, it's because they didn't produce enough renewables.
Scale factories takes time. They are scaling factories at an impressive speed but it's still not enough, and of course it continues to grow.
https://www.pv-magazine.com/2023/06/08/ … w-by-2024/
The issue with cost, which you seem to be working overtime to ignore, is the cost of not having any energy. Renewables without storage are an absolute guarantee of having non-functional electric grids. After we do an LCOE on photovoltaics or wind turbines and batteries or any of the other storage solutions proposed by our green energy fans, you no longer have an argument to make about the cost of renewables being cheaper than the cost of hydrocarbon fuels.
They are two different markets. A market with a mix of non-dispatchable renewable (as solar and wind) with others that it can do it (like hydro or natural gas) and as the market move through more and more wind and solar, storage and other techniques needs to be added.
We are way below the level of require storage in most places of the world, so expect renewable to continue, while at the same time storage continue their advancements lowering the costs, waiting to reach the competitive goal of renewable+storage to beat natural gas.
What we can expect in coming years are a reduction in coal for electricity, replaced by renewables.
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