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#301 2024-01-29 05:00:10

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

kbd512 wrote:

How to Build a Low-tech Solar Panel?

George Cove, a forgotten solar power pioneer, may have built a highly efficient photovoltaic panel 40 years before Bell Labs engineers invented silicon cells. If proven to work, his design could lead to less complex and more sustainable solar panels.

Apparently, we can make photovoltaics without Silicon-based semi-conductors, which are potentially far easier to recycle than current photovoltaics and much longer-lived, with dramatically lower temperatures to fabricate these Tin-Antimony based semi-conductors.  Recycling would not involve toxic chemicals or grinding up the semi-conductor waste, and there may be no need to physically protect the device from the environment.  The downside is lower efficiency.  The use of more common and less energy-intensive semi-conductor materials probably negates any inefficiency in power production.

This is certainly a technology worth exploring.  But efficiency would need to increase beyond 5% for this to be a workable solution.  The problem is that the quantity of steel, concrete, glass, aluminium and copper used to construct a conventional solar PV powerplant are an order of magnitude greater than a windfarm in an average location, which is in turn an order of magnitude more resource intensive than a light water reactor producing the same energy in a year.  The embodied energy of the materials used in a solar PV system, mean that its energy return on investment is already marginal in most climates where these things are built.  If the panels are less efficient, then embodied materials and energy are multiplied even further.  The plant will never break even on its embodied energy.  That isn't to say that this development isn't worth pursuing.  But there would need to be progress on efficiency.

Kris DeDecker's article on small PV systems is interesting in itself.  It tells us a lot about how to optimise these systems to reduce cost and improve EROI. One of the points he makes is that 80-90% of lifetime costs in a small system result from the battery and its charge controller.  The inverter, which converts DC to AC is also expensive and has limited life.  His suggestion: Use low voltage DC power from the panels without inverters.  Also, do not attempt to store more than a small quantity of solar power.  Instead, use it directly as it is being generated.  This cuts out a lot of the cost and embodied energy of the system.  But it does force the user to make use of the power when it is being generated, rather than storing it for when convenient.  It has other implications as well.  If power is being generated and used as low voltage DC, transmission distances need to be very short.  Keeping resistance losses low requires thick conductors, which are a financial and energy cost in themselves.  So the consuming devices need to be in proximity to the panels.  DC appliances are non-standard, which also increases costs and limits options.

The conclusions from this article apply to any PV system we deploy on Mars as well.  (1) Do not attempt to store power, use it as it is generated.  (2) Use the low voltage DC that the panel produces, do not convert to AC.  (3) Install the panels close to where power is consumed.  Do not transmit more than a few feet.  There will be applications that are compatible with these limitations.  So solar PV will certainly be part of the solution on Mars.  But it doesn't appear to be suitable for providing grid scale electric power or the energy needed for industrial high heat and chemical production.  It is suitable for providing small amounts of power in situations where it can be used at source, where intermittency doesn't matter.  If we wanted to run a machine shop for making small components or servicing vehicles, solar power would be a workable solution.  Power doesn't need to be stored if the shop is only used for an 8-hour workday.  We could reduce transmission distance by using the solar power to drive a compressor supplying air tools.  But we wouldn't use solar PV to provide 24/7 baseload power or to smelt the metals that are being machined.  It is a technology that is useful in filling specific niche applications.

Last edited by Calliban (2024-01-29 05:26:52)


"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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#302 2024-01-29 07:22:37

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

kbd512 wrote:

Calliban,

If wind turbines can be designed to directly produce heat and pressure to circulate a working fluid through a centrally located electric generator, then we don't need to synchronize hundreds to thousands of electric motors to the grid.  This is the way all commercial electric power plants were intended to operate, and did operate, prior to using intermittent energy.  They did not require control electronics to operate, or if they did, they were all located in one place.  Solar thermal provides the same ability to install a generator hall.  This is doable.  It's a model for a sustainable user maintainable implementation of wind and solar power.  Any decent commercial plumber or electrician knows how to make that work.  It's something that can be taught to new hires within a few months of on-the-job training.  It doesn't require an electrical engineering degree prior to even thinking about working on the system.

I concur.  Power transmission from the nacelle to ground can take place through a vertical shaft that rotates and drives a hydraulic pump at the bottom.  The horizontal hub shaft in the nacelle can drive the vertical shaft using a bevel gear.  A fan tail could be used to keep the nacelle facing into the wind, removing all electronics from the turbine.

The hydraulic lines would carry pressurised oil or water glycol to the central generating station.  A certain amount of energy can be stored in both raised weight accumulators and within a flywheel attached to the central generator.  This lengthens any power transients which otherwise create rapid frequency fluctuations that have proven to be a problem with intermittent energy sources.  If we wanted to be really efficient, we would couple a gas turbine to the same generator set using its own hydraulic transmission system.

A well organised system would use some of the hydraulic power to run a heat pump for a town district heating system, by coupling a hydraulic turbine to the heat pump compressor.  Heat is one form of energy that can be affordably stored cheaply for relatively long periods, in an underground tank.  We would use half of the energy produced by the wind farm to do this and switch the heat pump on when there was excess hydraulic power.  The electrical generator in the powerplant could then be made smaller, but would achieve a higher capacity factor.  This would reduce the demand for the gas turbine, which has relatively low capital cost but high fuel cost.  So a 3GW-peak wind farm, would drive a 500MWe hydraulic powerplant at 80% capacity factor and 2500MW mechanical heat pump at 25% capacity factor.

Next question is: Can we integrate the use of solar power into such a system?  Stored solar thermal power is obviously useful as input to the heat pump.  Can we use solar to generate mechanical power as well?  In places where there is an abundance of sunshine, solar thermal can drive a steam plant.  The steam turbine could drive a hydraulic pump.  But it could be useful in PV systems as well.  One way of reducing the resource requirements for a PV set up, would be to couple PV panels to positive displacement hydraulic pumps.  These would convert low voltage DC into mechanical power, which supplies a central generating station.

Last edited by Calliban (2024-01-29 07:39:52)


"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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#303 2024-01-29 11:13:08

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

It would appear that hydraulic wind turbines are under development.
https://www.tudelft.nl/en/me/about/depa … -turbines/
https://www.sciencedirect.com/science/a … 7X23000676

Maybe we will hear more in the years ahead.


"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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#304 2024-01-30 16:48:57

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

A new chemical reactor has been developed that allows the conversion of methane into heavier hydrocarbons with high efficiency.
https://cen.acs.org/environment/climate … eb/2021/11

A significant proportion of Earth's natural gas resources are stranded, meaning that it is not economically viable to transport them to markets.  An obvious solution is to convert the natural gas into a liquid that can be shipped.  One option is to cryogenically cool the gas to -160°C and ship it as a saturated liquid.  But this is quite energy intensive, very capital intensive to set up and has minimum practical scale.  If natural gas can be converted into a storable liquid fuel at close to ambient temperature and pressure, it greatly simplifies shipping it to markets.  It also makes it a more valuable product that is suitable for vehicle fuel.  If this innovation can be scaled up, it would do a lot to extend the availability of liquid fuels, mitigating concerns over depletion.

On Mars, it would certainly be useful to have an energy efficient mechanism for converting methane into propane.  Liquid propane is denser than liquid methane and is a liquid at -42°C at 1 bar pressure.  This is above Martian night time temperatures.  This would make propane easy to store in lightly pressurised steel tanks.  We would cover these in a layer of regolith to protect them from daytime heat.  At night, a simple flat plate radiator could use the low Martian sky temperature to cool the propane.  This is something that would work better on Mars than on Earth.
https://www.engineeringtoolbox.com/prop … _1020.html

Last edited by Calliban (2024-01-30 17:10:41)


"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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#305 2024-01-31 05:06:58

Terraformer
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From: The Fortunate Isles
Registered: 2007-08-27
Posts: 3,904
Website

Re: Why the Green Energy Transition Won’t Happen

Oooh, propane should be a lot easier to store than methane. And turbines can be built to run on propane (they can run on petrol, too. Low natural gas prices seem to be the reason we don't. But we could, if we were concerned about keeping the grid going with shortages of natural gas.)

Needs a lot of heat, but perhaps doable when the sun shines? It looks like it might be something we could do as a batch process.

Propane seems to be usable for aircraft?


Use what is abundant and build to last

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#306 2024-01-31 17:17:41

SpaceNut
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#308 2024-03-21 10:06:09

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

The latest article from Low Tech Magazine discusses humanity's insane appetite for steel.
https://solar.lowtechmagazine.com/2024/ … -iron-age/

Global steel production sits around 2 billion tonne per annum.  It is second only to concrete as humanity's most used industrial material.  There is a lot of discussion on the use of steel in energy supply, which accounts for 10% of total human steel use.

Wind power is by far the most steel intensive energy source.  One thing that I hadn't realised is that the amount of steel needed per MW capacity actually increases as turbines get larger.  So a 5MW turbine needs a lot more than 5x the steel than a 1MW turbine.  The giant multi-MW turbines that are now being built are therefore critically dependant on the continued availability of steel at a low enough cost.

According to DeDecker, a 5 MW wind turbine with a 150-meter tall tower needs 875 tons of steel (175 tons/MW).  The capacity factor of wind turbines is typically around 33%.  So using 5MW wind turbines, we need to invest 525 tonnes of steel for each average MW of electric power.  Could we power the entire world using the wind?  Lets leave aside problems associated with storage, transmission and intermittency.  Global electrical energy demand is running at 25,000TWh per year.  That is equivelent to a continuous demand of 2.85TW, or 2,850,000MW.  To supply that power with 5MW turbine would require a total steel investment of 1.5bn tonnes.  That is almost as steel as the entire world uses in 1 year.  I think it could be done.  But it would be a huge undertaking.

Light water reactors require 20-40 tonnes of steel per average MW.  Most of this is low alloy steel used for reinforcing.  Stainless steel used in the primary circuit and steam range is a much smaller component.  Taking the figure of 40te per MW, how much steel would be needed to power the world using nuclear reactors?

M = 40 x  2,850,000 = 114m tonnes.

This is still a lot, but is a lot less less than 1.5bn tonnes.

Last edited by Calliban (2024-03-21 10:24:46)


"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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#309 2024-03-21 10:51:46

Terraformer
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From: The Fortunate Isles
Registered: 2007-08-27
Posts: 3,904
Website

Re: Why the Green Energy Transition Won’t Happen

Hmm. I wonder how the steel requirements compare for Vertical Axis Wind Turbines?

Contra-rotating floating turbines promise unprecedented scale and power

There's been a trend in wind power to go for larger and large individual turbines, but that's not necessarily the way to optimise for costs. VAWTs can be clustered together in ways HAWTs can't be, and not being top heavy their foundations should require far less engineering work. If they have foundations at all.

They might take up more space, but *gestures at the north sea*


Use what is abundant and build to last

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#310 2024-03-21 17:16:05

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,428

Re: Why the Green Energy Transition Won’t Happen

Energy startup designs 'reverse coal mining' reactor that offers practical solution to air pollution: 'There wasn't enough being done'

Minnesota company Carba is helping to slow down an overheating planet by pulling its solution right from the air. 

As detailed by the Star Tribune, the clean-energy startup designed a proprietary reactor that is able to turn carbon dioxide (CO2) into a "charcoal-like substance," which can then be repurposed as a product or buried underground for more than a thousand years.

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#311 2024-03-27 06:12:19

Spaniard
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From: Spain
Registered: 2008-04-18
Posts: 133

Re: Why the Green Energy Transition Won’t Happen

Last update data from IRENA

Website: https://www.irena.org/Publications/2024 … stics-2024

Document link:
https://mc-cd8320d4-36a1-40ac-83cc-3389 … s_2024.pdf

2023 growth for wind and solar

Wind: From 901.231 MW to 1.017.199 - 12,8% growth

Solar: From 1.073.136 MW to 1.418.969 - 32,2% growth

Last IEA projection about 2023 was a 2% year growth. We will soon get IEA updated data to confirm this.

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#312 2024-03-27 10:15:34

kbd512
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Registered: 2015-01-02
Posts: 7,826

Re: Why the Green Energy Transition Won’t Happen

Spaniard,

Reuters: Global coal exports and power generation hit new highs in 2023

Worldwide electricity generation from coal hit record highs in 2023, while thermal coal exports surpassed 1 billion metric tons for the first time as coal's use in power systems continues to grow despite widespread efforts to cut back on fossil fuels.

Coal-fired electricity generation was 8,295 terawatt hours (TWh) through October, up 1% from the same period in 2022 and the highest on record, according to environmental think tank Ember.
...
Emissions from coal-fired electricity generation also hit new highs through October 2023, topping 7.85 billion tons of carbon dioxide and equivalent gases, around 66.7 million tons more than during the same period in 2022, according to Ember.
...
The continued expansion in coal use and emissions provides a stark reminder to climate trackers that the high-polluting power fuel remains integral in key power systems even as solar, wind and other clean energy sources are deployed at a record rate.
...
Globally, around 82% of all coal-fired electricity generation occurred within Asia in 2023, up from an average of around 75% in 2019.

Asia's share of coal use and imports should continue to climb as other regions further reduce coal consumption.
...

Those people in Asia are producing all of your green energy machines.  Europeans don't mine Copper, they don't smelt Aluminum, they don't make photovoltaic panels, NdFeB permanent magnets, or any of the other heavy industrial activities that make your green aspirations a reality.

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#313 2024-03-27 13:24:32

kbd512
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Registered: 2015-01-02
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Re: Why the Green Energy Transition Won’t Happen

IEA - Global gas demand set for stronger growth in 2024 despite heightened geopolitical uncertainty

There was record production and consumption of oil in 2023 as well.

World-production-and-world-consumption-of-crude-oil-and-other-liquids-per-day-for-the.png

Believe whatever you wish to believe about this, but it happened and will continue to happen until we either run out or devised more intelligent ways to stop consuming so much oil.

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#314 2024-03-27 14:56:43

Terraformer
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From: The Fortunate Isles
Registered: 2007-08-27
Posts: 3,904
Website

Re: Why the Green Energy Transition Won’t Happen

I wonder what specifically led to the 10% dip in 2020? I'm guessing it was reduced driving, afaik we didn't have a massive manufacturing slump that year? And cars/trucks make up a sizeable fraction of oil consumption.


Use what is abundant and build to last

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#315 2024-03-27 15:12:20

kbd512
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Posts: 7,826

Re: Why the Green Energy Transition Won’t Happen

Terraformer,

All the people who lost their jobs in 2020 would probably disagree with you.  You don't like cars and think they're not useful, but you're in the minority, and benefit from their use whether you have the intellectual honesty to admit that to yourself or not.

During 2020, the world's collective gross domestic product (GDP) fell by 3.4 percent. To put this number in perspective, global GDP reached 84.9 trillion U.S. dollars in 2020 – meaning that a 3.4 percent drop in economic growth results in over two trillion U.S. dollars of lost economic output.

When you devise an economic activity to replace those lost 2 trillion dollars, which does not involve transport of goods or people using motorized vehicles, do let us know.

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#316 2024-03-27 15:50:55

Terraformer
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From: The Fortunate Isles
Registered: 2007-08-27
Posts: 3,904
Website

Re: Why the Green Energy Transition Won’t Happen

kbd,

Why are you like this. You always answer innocuous questions in a really aggressive manner as if you've been personally offended. Go reread my post and highlight where I talked about lockdowns being brilliant and how it was great people lost their jobs.


Use what is abundant and build to last

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#317 2024-03-27 20:31:00

kbd512
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Re: Why the Green Energy Transition Won’t Happen

Terraformer,

Apologies.  I'm not real happy with the results of the lockdowns, in case you couldn't tell.

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#318 2024-03-29 12:22:34

Spaniard
Member
From: Spain
Registered: 2008-04-18
Posts: 133

Re: Why the Green Energy Transition Won’t Happen

kbd512 wrote:

Spaniard,
Coal-fired electricity generation was 8,295 terawatt hours (TWh) through October, up 1% from the same period in 2022 and the highest on record, according to environmental think tank Ember.

Yes. Even with the new data, renewables aren't YET enough to make fossil fuels peak.

Still, you don't need advanced mathematics to see that if the trends continue, with one source growing slowly and the others growing pretty fast, it won't take too much time to happen.

Just as a simple calculation. With 400 GW new of solar, that could generate as an average 100 GW more or less, that could be like a 0,5% of our energy consumption. You would need a x200 factor to generate as much solar as our current consumption.

2^8 = 256

If you duplicate the solar power eight times, you will generate more energy than consumed today.
At that growth speed, you duplicate solar energy each 3 year (in fact in less). So in 24 you could generate that level of solar.

I'm not saying that it will occur that speed. Of course, the speed will slow in the future because some bottlenecks and local market saturation. I'm just posting some numbers to expose how astonishing a 32% yearly growth is and why we shouldn't be surprised if fossil fuels peaks in coming years.

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#319 2024-03-29 16:00:37

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,428

Re: Why the Green Energy Transition Won’t Happen

Not sure of the reason but the news on the radio indicated that a coal fired power plant was being shut down but it's going to take many more.

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#320 2024-03-29 18:47:42

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

Spaniard wrote:
kbd512 wrote:

Spaniard,
Coal-fired electricity generation was 8,295 terawatt hours (TWh) through October, up 1% from the same period in 2022 and the highest on record, according to environmental think tank Ember.

Yes. Even with the new data, renewables aren't YET enough to make fossil fuels peak.

Still, you don't need advanced mathematics to see that if the trends continue, with one source growing slowly and the others growing pretty fast, it won't take too much time to happen.

Just as a simple calculation. With 400 GW new of solar, that could generate as an average 100 GW more or less, that could be like a 0,5% of our energy consumption. You would need a x200 factor to generate as much solar as our current consumption.

2^8 = 256

If you duplicate the solar power eight times, you will generate more energy than consumed today.
At that growth speed, you duplicate solar energy each 3 year (in fact in less). So in 24 you could generate that level of solar.

I'm not saying that it will occur that speed. Of course, the speed will slow in the future because some bottlenecks and local market saturation. I'm just posting some numbers to expose how astonishing a 32% yearly growth is and why we shouldn't be surprised if fossil fuels peaks in coming years.

It is easy to make sweeping statements like that if you ignore the material realities of what would be required to make it real.  Unless there is some fundamental change to the way solar power actually works, it will be impossible to sustain that rate of growth for more than a little while longer.  Here are the material requirements for a 1MWe solar PV powerplant.
https://solaredition.com/raw-materials- … lant-2017/

Global electricity production is about 28,000TWh per year.  Overall primary energy consumption is over 6x that.  We would need to expand electricity production about 4x if all energy were to be supplied electrically, i.e. by solar.  To do that using solar PV and some combination of storage and electrolysis:

Flat glass production would need to roughly quadruple.
Copper production would need to double.
Aluminium production would need to double.
Steel, concrete and plastics production would need to increase between 5-10%.

Those last three sound achievable, until you realise that these materials will somehow have to be mined and processed using solar power.

This is only for the powerplants.  It doesn't include the materials needed for energy storage plants, electrolysis plants, battery systems, transmission systems, etc.  Electrical transmission will need to be extended significantly.  It needs enough capacity to handle peak generation from the solar plants, which will be at least 4x average generation, if you are assuming a capacity factor of 25%.  Incidentally, that is optimistic for solar capacity factor.  Most of the locations that can achieve that are far from where people live.

There are are other technologies that are more scalable than PV systems.  Solar thermal power is much hungrier for steel than PV.  But it requires less copper and aluminium, because power is generated in a relatively large thermodynamic plant.  Steel can be recycled efficiently and there are no near term constraints on iron ore resources.  If we are to scale up solar to produce the TW power levels needed by humanity, solar thermal is how it will have to be done.

At present, almost all of the materials needed for the green transition are produced using fossil fuels.  It will be very difficult and expensive to produce materials in the volumes needed using renewable energy.  In many cases, we aren't even sure how it can be done.

Last edited by Calliban (2024-03-29 19:13:32)


"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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#321 2024-03-29 22:48:59

kbd512
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Registered: 2015-01-02
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Re: Why the Green Energy Transition Won’t Happen

Spaniard,

I really hope you're right, but I think what will actually happen, is that hydrocarbon fuel consumption goes up over the entire period of time we're building all of this new renewable energy equipment.  Hydrocarbon fuel consumption will never become "less" over that period of time, because less implies further dramatic energy efficiency improvements, which only generates more demand, or else we start making wind turbines and solar panels by using other wind turbines and solar panels.  Essentially, we either quit demanding high energy materials or most of said materials must be made using electricity not produced by hydrocarbon energy.  Thus far, we're not doing anything like that at all.  If we demand an exponential increase in renewable energy over a very short period of time, then we're going to burn whatever coal, oil, and gas we have left to do that.  That means CO2 emissions will go up by the same amount.

A semiconductor can theoretically be made using electrical energy to make the Silicon wafers.  In actual practice, which frequently diverges from theory, we're burning metallurgical grade coal to do that.  Until I see widespread implementation of all-electric Silicon wafer fabrication, I will not just assume that we're going to do that in the near future.  Electric induction heating has existed for many decades now.  All of the largest Iron smelters still use coal or gas.  There is not one alternative method with any real capacity to speak of.  Proving that you can do something one time doesn't mean it's practical to do at greater scale.

You, along with so many others, seem to view electrification as a panacea.  It's thermally powered?  Well, then, it must be really inefficient.  Let me break out my magic electric wand.  Shazam!  Now it's "efficient" because it uses electricity.

Let me use some simple math to illustrate my point about thermal vs electrical energy.

A garden variety photovoltaic panel is about 25% efficient at converting photons into electricity.  Some can do better, some do worse, but for a single-junction monocrystalline cell, 25% is good and we'll assert that it can do that over its entire lifetime of about 25 years.  This would account for higher initial or lower end-of-life efficiency.  In a desert climate, 1m^2 of said panel could reasonably be expected to produce 1MWh of electricity.  Let's call it 2,500Wh per day for easy math, so 912.5kWh per year.  Over 25 years, that's 22,812.5kWh of power generated.

A polished curved plate of Aluminum, or merely an Aluminum coated plate of stamped sheet steel, also 1m^2 in area, shaped to concentrate reflected photonic power onto a receiver tube above the trough, will reflect and thermalize at least 90% of the photonic energy that strikes it from the Sun.  In the process of transferring the thermal energy through the entire power plant, let's assert that we lose another 15% of the total input energy.  Under the same conditions, that same polished reflector generates 7,500Wh per day, so 2,737.5kWh per year.  Over 25 years, that's 68,437.5kWh of power generated.

After 25 years of operation, the Aluminum will still be a shiny piece of polished Aluminum, and produce as much power as it did the day it was made.  That will not be the case for the photovoltaic panel, which is why the old panels eventually need to be replaced.

After 25 years of operation, a brand new photovoltaic panel, plus all the electrical wiring and plastic, needs to be reproduced, and the energy required to do that is non-trivial.

Now let's consider what the single largest task is for this green energy power generation proposition:

Heating and cooling accounts for about half of the global final energy consumption. It is the largest source of energy end use, ahead of electricity (20%) and transport (30%), and is responsible for more than 40% of global energy-related carbon dioxide emissions.

Even if I foolishly opt to convert all of my thermal power to electrical power, if my conversion process is 50% efficient, I still have 50% more power to work with.  If I semi-intelligently recognize and accept that most of the energy used by humanity is direct or indirect low grade heat energy, then I can do better still, because the product being delivered will be the same product that electrical energy produces- hot or cold air and water.  The technology at work here is a refrigeration loop by any other name, concentrating hot 100C or cold 0C through heat exchange.

A dishwasher doesn't require any electricity to operate, it requires hot water and pressure.  It doesn't need to be made miraculously more efficient through the use of electricity.  Not having electricity and hot water both running through the same device is a bonus.  You spoke at length about the circular economy, and how important it was.  Things that are either deliberately or unavoidably designed to fail over a short period of time are not part of that economy.  Unfortunately, that describes every modern computerized device made.  There's nothing "circular" about the cell phone economy, for example.

A dishwasher that contains no electronics or electric motors that fail in ways which prevent economical repair, is one way to achieve that goal.  There are simple mechanical devices that can keep time with the precision required for a dishwasher.  They existed long before batteries or 555 timer integrated circuits did.  There are simple ways to deliver hot water and hot air that don't require a single kilo of Copper.  Since there's nothing electronic or electrical to fail, so long as the device is fed hot and cold water, it will continue to wash and dry your dishes.  The seals will fail before the device fails to function.  Seals can be economically replaced.  If a 555 timer integrated circuit fails, you can't open it up and repair or replace that silly little chip for any reasonable amount of money.  If you have the skills, maybe you can do it yourself, but nobody who repairs dishwashers is going to do anything except replace the entire circuit board it's soldered to, or tell you to buy a new dishwasher.  When my mechanical timer starts to fail, I squirt a tiny amount of oil into the gears and cogs, and then it works as if it were new, even though it's not even close to being brand new.

You know what would have a monumental impact on both burning less hydrocarbon fuels and this fabeled circular economy?

Mandating that devices that don't need to be electrified or computerized or motorized, aren't.  Thermal power is delivered as direct thermal power from a thermal power plant that doesn't need to be completely replaced every 15 to 25 years.  A refrigerator doesn't need an internet-connected computer inside it.  A dishwasher doesn't need a computer inside it.  A toaster for damn sure doesn't require a microchip.  Said devices do need to last for at least the lifetime of their original owner.  The ones made with microchips and electronics never last that long.

A man came to our house today to install a computerized water meter.  I asked him if the old mechanical meter was broke or malfunctioning.  He said the old meter was fine, but they were replacing all of the water meters in our area with electronic water meters.  He said the batteries were supposed to last for 10 years, but the screens used to read the meters often fail within their first year of operation if the tech who comes to read the meter forgets to close the cheap plastic lid on the electronics enclosure.  He said that the plastic enclosure will also deteriorate if the enclosure over the meter is not kept closed, and the device itself is apparently not very waterproof.  It's a non-waterproof water meter that's buried in the ground in place that routinely sees light flooding.  The old meter has operated for at least 15 years that I know of.  A perfectly good working water meter that would faithfully perform its job for the rest of my life was replaced with electronic trash that will probably fail within its first year of operation.

That is not a "circular economy", it's a "circular jerk".  Why are we being forced to participate in this insufferably stupid circle jerk?  Because the people "running the show" now are a bunch of jerk offs who may have all the information in the world, but they're too stupid to know what to do with it.  Someone who spends money to replace something that is not broken, that they know for damn sure will break inside of ten years, if not one year when some meter reader forgets to close the cover, is the dictionary definition of a jerk off.  I don't care what education they have or don't have, they're still a jerk off.

You're hoping and praying that these scientologist jerk offs will deliver a circular economy... by making a bunch of new electronic trash that's deliberately designed to fail early and often.  Their intent is totally irrelevant.  Only results matter.  I'm not a gambler, but if I was, I would bet the farm that this sort of utter nonsense fails.  All the warning signs are there that it's failing, but some people are very obsessive about things they find aesthetically pleasing.  I think circular economy is a quaint idea, but nature recycles CO2 and Hydrogen.  Nature does not demand Aluminum, Copper, Nickel, Silicon, Neodymium, Boron, steel, concrete...  The list of materials required for this green circular economy to take shape is practically endless, and they must be made available in enormous quantities, else it doesn't work for the vast majority of people now living on planet Earth.  It's almost as if it was intended to fail.

After this circular economy grift fails hard, they'll move on to the "infinity loop economy", which will be an even more absurd form of the circular economy.  When that also fails, it'll be the "3D infinity loop economy", more BS wrapped up in a bowtie.  With any luck, I'll be dead and gone by then.  We haven't hit "peak stupid" yet, so the stupid must continue until most people come to terms with how stupid this has all become.  The entire belief that we can build more and more very short-lived yet energy-intensive machines that require an ever-increasing percentage of the total energy supply, while somehow using less energy input to do it, through the "magic" of electricity, is painfully dumb.

Could all these people be budding geniuses and I'm some just another dinosaur moron who can't appreciate their brilliance?

Absolutely.  I have to admit that much to myself and everyone else, or I'm not being honest.  The people proposing this vanity project won't even admit that their beliefs about how this will ultimately work out, could possibly be wrong, which is why I think that they almost certainly are wrong.  They don't have any backup plan, which tells me they're not strategic long-term thinkers.  Throwing all of your resources at a single solution rarely provides desirable outcomes.  The amount of magical thinking involved with energy is truly astonishing.  The water meter is a clear example of how money, energy, materials, and labor can all be expended without worthwhile results.  It does tend to keep people busy and unable to evaluate results, given the constant change, so maybe that is its true purpose.  The people in charge know there's a serious problem, but they also know they cannot solve it, because they don't know what a proximal solution looks like, or the solution would be very unpopular.  In the absence of true achievement, enough activity will at least avert attention away from the otherwise obvious fact that there's no realistic long term solution in place to contend with energy and resource depletion.  The current solution on offer (renewable energy and circular economy) looks an awful lot like, "we'll just consume more".  And so we will, until we cannot.

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#322 2024-03-30 05:42:22

Spaniard
Member
From: Spain
Registered: 2008-04-18
Posts: 133

Re: Why the Green Energy Transition Won’t Happen

Calliban wrote:

It is easy to make sweeping statements like that if you ignore the material realities of what would be required to make it real.  Unless there is some fundamental change to the way solar power actually works, it will be impossible to sustain that rate of growth for more than a little while longer.  Here are the material requirements for a 1MWe solar PV powerplant.
https://solaredition.com/raw-materials- … lant-2017/

Global electricity production is about 28,000TWh per year.  Overall primary energy consumption is over 6x that.  We would need to expand electricity production about 4x if all energy were to be supplied electrically, i.e. by solar.  To do that using solar PV and some combination of storage and electrolysis:

I already explained why you are doing wrong reasoning.

You are multiplying the raw materials of CURRENT PV by the power need, obtaining that you will reach a limit.

But you are ignoring that the reason why the current PV are made like this it's because it's the most cost-effective model under our current variables. It's not because it's an intrinsic dependency.

From a different perspective. We can replace most of copper in current PV for aluminum because it's used mostly on wires. It's just it has other problems and under current copper price, copper it's the best solution (from economic perspective). It's the same for silver inside PV. Copper can be used in that place.
In that functionality, it's a minor quantity. You can replace silver by copper, and some copper conductors by aluminum, and you will reduce the total copper per kw and even remove silver dependency entirely.

Of course, it's expected that this technology can be a little worse than the same with better elements if the price is not relevant. But things change when it's become relevant.
Besides it's a same technology evolution comparison. A 2030 lower quality lower material PV vs 2030 premium better materials PV.
If you compare technologies of different generations, things could be different. In any case, it will be the most cost-effective and that's the most important factor to massive adoption.

You are assuming that PV is not the right technology because your material projections said that PV uses too many materials, but the thing is we use that, because it's the most effective TODAY.

You can't still compare low-material PV against other sources of energy because this kind of PV is not available as a mass production unit, but you are already assuming that PV will fail, while I expected that it still be the cheapest more available source of energy on Earth and the cost curve will continue to reduce or worst case maintain a average flat which current cost projected into the future.

As I said, I don't expected a ~30% growth up to the saturation point. In fact, this kind of deployments usually went through an S-curve. Besides, it's not an unique deployment but a lot at the same time, each one with a different S-curve, which makes the total curve a little more complex than expected.

Still... I don't expect any hard stopper to renewables. More from the demand side than the production side. There is no point in produce more and more solar if the demand can't use that energy in a profitable manner. So that depends in a lot of other sides advancements, like storage, better demand adaptation, better electric networks and change industry process from thermal to electricity.


Calliban wrote:

Flat glass production would need to roughly quadruple.
Copper production would need to double.
Aluminium production would need to double.
Steel, concrete and plastics production would need to increase between 5-10%.

Those last three sound achievable, until you realise that these materials will somehow have to be mined and processed using solar power.

This is only for the powerplants.  It doesn't include the materials needed for energy storage plants, electrolysis plants, battery systems, transmission systems, etc.  Electrical transmission will need to be extended significantly.  It needs enough capacity to handle peak generation from the solar plants, which will be at least 4x average generation, if you are assuming a capacity factor of 25%.  Incidentally, that is optimistic for solar capacity factor.  Most of the locations that can achieve that are far from where people live.

You are just mixing variables to make it apparently difficult, but that all energy has already being accounted in calculations. Or did you expect that current mining is not paid in actual PV?

So the only possible argument is that the mining model uses more energy using electricity instead of fossil fuels. But I don't see any reasonable reason to think that.

In fact, I'm not even sure if they will be more mining if we replace fossil fuels for renewables. Yes, it will be (a lot) more mining of CERTAIN materials, but current coal also require a lot of mining for example. It will change from one elements to others.

But even if the total numbers where greater, if the problem is not exhaustion (that the argument it's the previous one), that mining is already accounted in the current production, so... what's the problem of scale the model?

If we need more materials, we open more mines. And yes... that mines could work on renewables... with extra technologies, of course (batteries, other energy vectors, in situ infrastructure adapted to use electricity, etc.). But it can be used.

Calliban wrote:

There are are other technologies that are more scalable than PV systems.  Solar thermal power is much hungrier for steel than PV.  But it requires less copper and aluminium, because power is generated in a relatively large thermodynamic plant.  Steel can be recycled efficiently and there are no near term constraints on iron ore resources.  If we are to scale up solar to produce the TW power levels needed by humanity, solar thermal is how it will have to be done.

At present, almost all of the materials needed for the green transition are produced using fossil fuels.  It will be very difficult and expensive to produce materials in the volumes needed using renewable energy.  In many cases, we aren't even sure how it can be done.

I insist, your view on the problem is wrong. Market is not driven by the "less resource" concept but the most "cost effective", and you are judging against PV because under current cost-effective choice of materials it uses more than the others. You are assuming that PV can't work with less materials or than under that circumstances won't be competitive against that options of yours, and that's a wrong assumption.

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#323 2024-03-30 19:09:39

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Why the Green Energy Transition Won’t Happen

Spaniard wrote:
Calliban wrote:

It is easy to make sweeping statements like that if you ignore the material realities of what would be required to make it real.  Unless there is some fundamental change to the way solar power actually works, it will be impossible to sustain that rate of growth for more than a little while longer.  Here are the material requirements for a 1MWe solar PV powerplant.
https://solaredition.com/raw-materials- … lant-2017/

Global electricity production is about 28,000TWh per year.  Overall primary energy consumption is over 6x that.  We would need to expand electricity production about 4x if all energy were to be supplied electrically, i.e. by solar.  To do that using solar PV and some combination of storage and electrolysis:

I already explained why you are doing wrong reasoning.

You are multiplying the raw materials of CURRENT PV by the power need, obtaining that you will reach a limit.

But you are ignoring that the reason why the current PV are made like this it's because it's the most cost-effective model under our current variables. It's not because it's an intrinsic dependency.

From a different perspective. We can replace most of copper in current PV for aluminum because it's used mostly on wires. It's just it has other problems and under current copper price, copper it's the best solution (from economic perspective). It's the same for silver inside PV. Copper can be used in that place.
In that functionality, it's a minor quantity. You can replace silver by copper, and some copper conductors by aluminum, and you will reduce the total copper per kw and even remove silver dependency entirely.

The short answer is yes, we can mitigate material shortages by using other materials.  Unfortunately, it doesn't help the overall sustainability of PV.  Here is why.

It is quite true that there are a continuum of options for designing something like a solar powerplant.  But design choices have real impacts on lifetime performance.  A balanced engineering design is all about reaching a compromise between competing interests.  But a lot of the design decisions that might make solar PV more sustainable from a resource perspective, would seem to have a negative effect on its energy return on investment (EROI), which is already poor.  This is ultimately a measure of how much energy you get out of an energy source over its lifetime, compared to the amount of energy required to build and maintain it.  The higher the EROI value of the energy sources supporting a society, the more prosperous and advanced that society will be.

Hall estimates that a purely agrarian society, without high levels of education or prosperity, could be sustained if EROI were 7-8:1.  That is a minimum survival level.  But if you want the really desirable aspects of civilisation, like universal healthcare, high technology and arts & sciences, EROI needs to be above 14:1.
https://www.issuesofsustainability.org/ … ciety.html

Without that, there just isn't enough wealth in society to support high civilisation.  Why is that? Because what humans call wealth is the result of energy acting on matter.  The higher the EROI, the less energy you must reinvest to sustain the energy source.  That means more surplus energy to go round and more wealth available for things that go beyond basic survival.

Why is this an issue for solar PV?  Hall and Prieto carried out the most comprehensive EROI study for solar PV to date.  Their analysis focused on the solar PV industry in your native Spain, which has some of the best solar resources in Europe.  Their conclusion?  The EROI of the solar PV industry in Spain is 2.45:1.
https://www.resilience.org/stories/2016 … weighs-in/

This is extremely poor.  So poor in fact, that it would be impossible for a civilisation powered by solar PV to both sustain the most basic services whilst also investing enough energy to keep supply stable.  Some countries are sunnier than Spain and some have better infrastructure.  The EROI may be better in Texas or Mexico.  But even if system EROI were to double, it wouldn't be enough to support any kind of society.  Solar PV investments appear profitable right now, because: (1) The powerplants are being manufactured using low cost coal based electricity in China; (2) Other generators carry the cost of providing backup power, through lost market share.

Lets talk about how material substitutions might impact the EROI of solar power.

1. What about substituting aluminium for copper conductors?  Aluminium has 63% of the conductivity of copper, but only 30% of its density.
https://en.m.wikipedia.org/wiki/Electri … nductivity

This means that a 1kg wire of aluminium, will conduct direct current electricity just as well as a 2kg wire of copper, assuming they are the same length.  Sounds good right?  There are applications where aluminium beats copper as a conductor.  In long distance transmission lines, we need a conductor with high strength per unit mass.  Copper may be a better conductor, but it is too soft and too heavy to support its own weight over long cable spans.  Why do we still use copper for home electrics, for windings around electric motors and extension cables?  Consider the amount of energy needed to make 1kg of aluminium: 155MJ.  To produce 1kg of copper requires 42MJ, on average.  Even though we only need half the mass of aluminium, the embodied energy needed to make an aluminium conductor of the same conductivity, will be 80% greater than a copper conductor.
https://en.m.wikipedia.org/wiki/Embodied_energy

We could replace some DC conductors with copper plated iron.  Iron has no near term supply issues.  The problem is that the conductivity of iron is only about 1/6th that of copper.  You would need 5.1x the mass of iron compared to a copper conductor.  Embodied energy of iron is ~25MJ/kg vs 42MJ/kg for copper.  So an iron conductor has 3x the embodied energy of a copper conductor.  This is the main reason why aluminium and iron are not used to replace copper conductors unless strength is the overwhelming priority.  Energy cost = monetary cost.

2. Can we reduce the amount of cover glass needed for solar panels?  The glass is there to protect the fragile PV material from abrasion, oxidation, UV damage and contamination.  We could use thinner glass.  But such panels will be more fragile and vulnerable to damage.  So a trade off is reached.  Departing from that trade off may still give you a functional product, but wastage will also be higher and so likely will be age related deterioration.  This reduces EROI.  The designers didn't just pull the design out of thin air.  It was chosen to balance such considerations as product longevity, age related decline in power output, weight and capital cost.  Using less glass won't neccesarily give better results.

3. Can we cut the use of aluminium in panel frames?  Again, yes.  But there is a price to pay.  We could replace aluminium with steel.  But that increases panel weight, manual handling issues and the size, cost and embodied of supporting frames.  Unless stainless steel is used, care would have to taken that steel frames are completely encapsulated (i.e drip galvanised).  Overwise, corrosion will reduce system life and again reduce EROI.

4. Could we use something other than steel in the support structure?  Yes.  To be honest, I have always suspected that a cast concrete support structure would have lower embodied energy than steel.  But concrete members must be thicker and heavier, because concrete is not as strong as steel.  This introduces other costs, such as increased labour costs constructing support stands.

In summary, it is possible to use substitute materials in solar PV plants.  But doing so degrades the already poor energetics of the system.  EROI needs to increase substantially for PV to be viable as a bulk energy source.

Last edited by Calliban (2024-03-30 19:21:24)


"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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#324 2024-03-30 21:10:42

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,826

Re: Why the Green Energy Transition Won’t Happen

Tons of Materials per 1GW of installed photovoltaic generating capacity
70,000t of Glass
56,000t of Steel
47,000t of Concrete
19,000t of Aluminum
7,000t of Silicon
7,000t of Copper
6,000t of Plastic

1kg of Glass from sand: 5kWh to 9.7kWh
1kg of Steel from Iron: 5.55kWh to 13.9kWh
1kg of Iron from ore: 5.55kWh to 6.96kWh
1kg of Aluminum from bauxite, 63.9kWh to 75kWh
1kg of Silicon Wafer: 2,108.7kWh to 2,154.9kWh
1kg of Copper from sulfide ore: 16.6kWh to 34.7kWh
1kg of Plastic from crude oil: 17.2kWh to 31.95kWh

1t of Glass from sand: 5MWh to 9.7MWh
1t of Steel from Iron: 5.55MWh to 13.9MWh
1t of Iron from ore: 5.55MWh to 6.96MWh
1t of Aluminum from bauxite, 63.9MWh to 75MWh
1t of Silicon Wafer: 2,108.7MWh to 2,154.9MWh
1t of Copper from sulfide ore: 16.6MWh to 34.7MWh
1t of Plastic from crude oil: 17.2MWh to 31.95MWh

1,000t of Glass from sand: 5GWh to 9.7GWh
1,000t of Steel from Iron: 5.55GWh to 13.9GWh
1,000t of Iron from ore: 5.55GWh to 6.96GWh
1,000t of Aluminum from bauxite, 63.9GWh to 75GWh
1,000t of Silicon Wafer: 2,108.7GWh to 2,154.9GWh
1,000t of Copper from sulfide ore: 16.6GWh to 34.7GWh
1,000t of Plastic from crude oil: 17.2GWh to 31.95GWh

For 1GW of installed photovoltaic capacity
350GWh Glass
621.6GWh Steel
1,214.1GWh Aluminum
14,760.9GWh Silicon Wafer
116.2GWh Copper
103.2GWh Plastic

17,166GWh of embodied energy for the materials alone, no transport or construction equipment energy, and excluding the concrete, for 1GW installed capacity.

Let's assume you get 5hrs of prime power per day, so 5GWh/day or 1,825GWh/yr or 45,625GWh over 25 years:
45,625GWh / 17.166GWh = 2.66 EROEI

If we include the concrete / transport / construction energy, then I'm guessing that 2.45 EROEI figure posted by Hall and Prieto is pretty close to reality for garden variety monocrystalline photovoltaics.  You barely get enough energy to recycle the materials 25 years later.

Edit:
These figures are the rosiest / minimum energy inputs figures for all materials, except the concrete, which I have not estimated, because energy input varies by quite a bit.  If your energy inputs are maximal or the equipment is deployed to a locale with poor solar insolation, especially energy inputs for the Silicon and Aluminum, then you may not even pay down the energy debt incurred by building and deploying the equipment, much less have power remaining for recycling and providing net positive energy injection into human society.  This looks like planning to fail from where I'm sitting.  I'm agnostic on the methods used, and only dogmatically religious about the achieved results.  Appearances mean nothing to me.  Aesthetics are worthless without results.

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#325 2024-03-31 04:20:42

Spaniard
Member
From: Spain
Registered: 2008-04-18
Posts: 133

Re: Why the Green Energy Transition Won’t Happen

kbd512 wrote:

Tons of Materials per 1GW of installed photovoltaic generating capacity
70,000t of Glass
56,000t of Steel
47,000t of Concrete
19,000t of Aluminum
7,000t of Silicon
7,000t of Copper
6,000t of Plastic

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.

That numbers are inflated. Glass is only used in panels, and you are accounting as glass more weight than the whole panel.
Not only that. Steel is rarely, mostly ever used in PV itself. The same for concrete. They are using in the side infrastructure to fix the panels in place and that depend a lot WHERE is that. There is no concrete in a roof.

Of course there is no need to use that materials explicitely. Still, they are commonly used in remote installations because they are cheap. The reason is that PV are light for the surface they cover, so if they aren't well fixed to something they have the risk of being blowing up by strong winds.
But here "Concrete" are just ballast. It's not common expensive concrete but materials done the cheapest (and less energy intensive) way possible.

It's the same for glass. There is a huge industry for making these elements for PV. Do you thing they are doing the things the same as average industry?
Remember than for renewable you expend energy TODAY to generate over the next 20 years. If real EROEI were as low as 4, the current consumption today would be 5 times the PV energy returned by year.
But here is the thing. China added 216 GW PV in 2023. Not only that but they almost produced a lot more exported.
216 GW will generate aprox 216*24*365*0,2*20 = 7.568.640 Gwh.
If you are assuming that EROEI is 4 you are saying that China used  7.568.640/4=1.892.160 Gwh  aprox to generate that PV

You know what? China consumed a little less than 45.000 twh in total. You are saying that China used 4% of their TOTAL energy for their PV industry.

And I guess the numbers would be similar for Wind.

And not only that, but they are still scaling more and more production lines, so the numbers won't stop growing.

If you continue this line of numbers you will soon conclude that China will soon run out of energy because renewable industry suck almost all energy from China. China growth in 2023 was 5%, so adding PV and Wind, China should already lacking useful energy because all energy is redirected to the renewable industry.

OR... you conclude that the numbers are wrong, and the energy used in the industry are a lot lower that these numbers, that it's probably the real thing.

In fact, I still waiting for a reasonable explanation why the PV industry has being lowering prices in a logarithm curve (yeah... in the last 30 years prices has go down for more than 90%), and still the people that calculate EROEI still argued that these numbers aren't changing. Or what kind of miracle makes the renewables to reach a price lower than just the sum of the energy involved in EROEI calculations (while it's the opposite. A lot of non-energy things must be added to the price), like they weren't paying for the raw materials used instead of selling the materials to the market directly or just consume it in their countries.

The reason is simple. That numbers has being decreasing over time. You would need to be an insider to have real current values, so don't expect to obtain actual values using old obsolete references.
Still, price is a good indicator, and it's what people inside the industry are using, not EROEI. And they said a completely different thing.

Last edited by Spaniard (2024-03-31 11:23:44)

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