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#251 2023-12-16 15:21:19

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,812

Re: Why the Green Energy Transition Won’t Happen

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#252 2023-12-17 19:03:57

kbd512
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Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

SpaceNut,

From your link in Post #251, I'm a little tired of this baseless figure being trotted out as "true" when it's often provably false:

Internal combustion engines convert gasoline to mechanical energy at 25% efficiency.

Where does that 25% figure come from?

Lycoming's O-360 engine has a Brake-Specific Fuel Consumption in cruise flight of around 0.45lb/hp-hr.

Edit:
135hp * 0.45 = 60.75lbs = 10.125 gallons of fuel consumed per hour of flight, at 135hp of engine output.

10.125 gallons * 33,700Wh per gallon of gasoline = 341,212.5Watt-hours of energy

341,212.5 / 745.7 = 457.57 horsepower-hours worth of energy in the gasoline consumed

135 / 457.57 = 0.295 or 29.5% efficient

Lycoming's engine uses a carburetor, a pair of magnetos for ignition, gear-driven accessories, and is normally driving 1 and often 2 alternators, along with a vacuum pump.  This is "prototypical", meaning a flight school can expect a run-of-the-mill O-360 to burn about that much fuel when leaned-out for a cross-country cruise flight somewhere between 5,000 and 10,000ft.  These engines don't have turbos, electronic ignition, or electronic fuel injection, and they're air-cooled, which means they have tons of blow-by in normal operation.  In short, their overall efficiency is absolutely abysmal by modern automotive combustion engine standards.  They would be considered "state-of-the-art" during the 1920s.  The O-360 was first run in 1952, and produced in almost identical form ever since.  In 2020, we call them "Lycosauruses", because there's nothing new or modern about them.

Edit #2:
For this same engine, electronic ignition improves engine power by about 4% (single EI system) 6% (dual EI system) according to Klaus Savier, an engineer who has built and sold electronic ignition systems for Lycoming (IO-360 / IO-540) and similar Continental (O-200 / O-300 / TSIO-520 / IO-550) 4 and 6 cylinder engines, or about 0.6075 gallons per hour for the same engine power.

320,739.75 / 745.7 = 430.12

135 / 430.12 = 0.314 or 31.4% efficient

EI allows the use of 9.5:1 compression pistons vs 8.5:1 for a standard O/360 / IO-360, while burning 100LL AVGAS.

With increasing the compression ratios, the BTE increases and BSFC decrease for all types of fuel used.

BTE = Brake Thermal Efficiency
BSFC = Brake-Specific Fuel Consumption

The generally accepted gauge for adding compression is that one full point of compression can add between 3 to 4 percent power. So, if an engine is making 50 horsepower and we add a full point of compression (from 11 to 12:1 for example), this could potentially push the power to 51.5 horsepower.

That means our higher-compression Electronic Ignition (EI) equipped engine is now 34.4% to 35.4% efficient.

For an engine running under constant high load with no turbocharging, no variable cam timing, no direct injection, and a rather modest compression ratio, that's remarkably efficient.  Engines which include those features can dramatically increase power output per liter / cubic inch of displacement.

The Lycoming IO-360 produces 180hp from 360 cubic inches of displacement.

Viking Aircraft Engines sells a Honda L15B7 turbocharged / direct-injected / VVT engine which produces 200hp from 91.54 cubic inches of displacement, at 260lbs of dry weight, which is almost identical to the O-360 (the IO-360 weighs a bit more).  Both engines have a wet / total installed weight that's nearly identical.

As luck would have it, we have BTE / BSFC maps for these Honda engines from the US EPA:
Benchmarking a 2016 Honda Civic 1.5-liter L15B7 Turbocharged Engine and Evaluating the Future Efficiency Potential of Turbocharged Engines

Last edited by kbd512 (2023-12-18 05:03:33)

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#253 2023-12-18 05:03:43

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

Shale oil and the slurping sound.  Interesting discussion between Nate Hagens and Art Berman on the impending decline of shale oil production in the US.
https://m.youtube.com/watch?v=qqTh2nBEcCs

Essentially, well productivity is declining.  Unless this reverses itself, total production will soon begin declining as well.

The US is not the only country in the world with tight oil reserves.  If we were still in a world where capital were cheap, we could maintain growth in global oil production by investing in development of international shale.  But global demographics are shifting and populations everywhere are ageing into retirement.  This makes capital more expensive.  If oil prices were able to rise into the $100+ range, it still might be proffitable to invest in these unconventional reserves.  The problem here is that there is a limit to how much GDP the world can generate from each barrel of oil.  This puts a ceiling on sustainable price before demand destruction begins.  The long shot is that global oil production will soon begin to decline due to a mixture of supply and demand related problems.  This will hasten the breakdown of globalisation.

The North American continent has enough unconventional reserves remaining to sustain a modern economy for a long time to come.  Europe is shrinking, but has enough collective military clout to get what it needs from Africa and Middle East.  It is the rest of the world, especially East Asia, that will be left hanging.  This is the 'end of the world' as Peter Zeihan described it.  The long period of post WW2 global industrialisation is coming to an end.  Increasingly, the countries that do well will be those favoured by geography.

Last edited by Calliban (2023-12-18 05:10:03)


"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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#254 2023-12-18 05:25:26

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

Calliban,

Since we clearly have nothing that's truly ready to replace oil, today would be a great time to start working out how to use intermittent energy to synthesize the most important petroleum products (gasoline, kerosene, and diesel) from scratch.  Whatever "the system" costs is a pittance compared to the breakdown of civilized society that will ensue without it.  We made a bad bet on electrification because it was a shiny new object of affection, rather than something practical with sound fundamentals.  We even continued to pursue electrification as a purported solution, despite knowing that it was even more wildly unsustainable than what we're presently doing.

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#255 2023-12-18 07:50:21

tahanson43206
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Registered: 2018-04-27
Posts: 16,943

Re: Why the Green Energy Transition Won’t Happen

For kbd512 re Post #254

It seems to me it is well documented, how to make synthetic fuel from various energy sources.

Where there may be gaps, we have topics where updates might be applied, to improve the collection of knowledge.

Here are topics that contain the word synthetic and which also apply to various energy sources...

Sticky: Synthetic or Natural Fuel Produced using Solar Power  by tahanson43206 [ 1 2 3 … 6 ]
Science, Technology, and Astronomy    133    2023-05-09 21:57:47 by tahanson43206

eFuel Plants - E-Fuel - Generic - Synthetic carbon based fuel by tahanson43206
Science, Technology, and Astronomy    4    2023-05-05 22:00:32 by SpaceNut

Synthetic Fuel Produced using Nuclear Power by tahanson43206
Science, Technology, and Astronomy    5    2023-04-06 10:31:50 by tahanson43206

Business Opportunity Synthetic Fuel from Solar/Wind Power by tahanson43206
Science, Technology, and Astronomy    4    2023-01-16 20:25:28 by tahanson43206

(th)

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#256 2023-12-18 09:20:24

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

The simplest solution and the one recommended by Zubrin, is to make methanol from various feedstocks.  If CO2 can be captured cheaply from ocean water (we have discussed that in the past), then:

CO2 + 3H2 = CH3OH + H2O

Methanol is a room temperature, atmospheric pressure storable liquid fuel, which can be stored in steel tanks without corroding them.  There are no issues with piping it long distances or storing large quantities of it.  A while back we discussed a solar thermal fuel manufacturing idea that would do all of this.  Methanol can be blended with gasoline, so this solution can be phased in gradually.  The only limiting problem is that methanol is corrosive to aluminium.  So the engines in new vehicles need to minimise the use of aluminium.  That isn't really a problem.  Where we need a diesel substitute:

2CH3OH = CH3-O-CH3 + H2O

This is dimethyl ether.  It is not corrosive to aluminium.  In liquid form it has about 3/4 the energy density of diesel and is suitable for compression ignition engines.  It has a vapour pressure of about 6 bars.  This could be used as jet fuel.

I can see this sort of initiative working in North America, where there is capital to support it and large areas suitable for solar thermal energy capture in the southern states.  It is less of an option in Europe, unless we really get our arses into gear and build out nuclear power.

One issue for the US is that the areas with the best solar resources tend to be away from the coast.  One way to solve that problem is to build ponds that can absorb CO2 from the air.  Another way is to use compressed air energy storage.  If air is compressed to high pressure at temperatures <31°C, the CO2 in the air turns into a liquid.  So we could colocate our fuel factories with CAES plants.

Air is 400ppm CO2, or 0.04% by volume and 0.06% by mass.  This means that each cubic metre of air we compress will give us 0.74g of CO2, which will make 0.54g of methanol.  This much methanol amounts to 10.76KJ of energy.  Compressing 1m3 of air to 10MPa, requires some 462KJ of energy.  So for every MWh of energy we store in compressed air, we get enough CO2 for 23.3kWh of methanol.  This isn't enough for a complete solution, but it is a start.

Interestingly, the gases dissolved in sea water are 1.6% CO2 by volume.
http://www.waterencyclopedia.com/Re-St/ … es-in.html

If we can use a CAES plant to degas sea water, then the feed gas is 40x richer in CO2 than ordinary air.  In this case, the CO2 is captured almost for free, as the CAES plant is compressing the air anyway.  The only additional energy cost comes from drawing a vacuum on the sea water to degas it.  Given that CO2 can be piped or even shipped as a liquid, the CAES plant doesn't need to be right next door to the fuel synthesis plant.

Last edited by Calliban (2023-12-18 09:52:31)


"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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#257 2023-12-18 10:06:40

Calliban
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From: Northern England, UK
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Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

Looks like someone has already considered CO2 capture from CAES.
https://www.sciencedirect.com/science/a … 1120330751

Classic CAES uses stored compressed air to provide the input air to a gas turbine.  This eliminates the energy consumed by the compressor, doubling the power output per unit of fuel burned, but it still burns natural gas.  The process isn't as efficient as one might expect, largely because the input air to the gas turbine is cold.  The compressed air provided by a regular GT compressor, carries all of the excess heat resulting from compression, which is then partially recaptured as work by the turbine.  At least some of thermal energy from the natural gas in a CAES system is used to replace this lost thermal energy, which is generated as heat during compression.

One way of avoiding the need for natural gas or reheating the compressed air on expansion, would be to expand the air adiabatically.  This will result in extreme cold air exiting the turbine, at temperatures far beneath freezing.  However, the cold can be stored by freezing liquid brine or methanol.  The cold can then be used to chill air prior to compression, reducing the work needed to generate compressed air.  This is a better option than attempting to store warm water and using it to reheat the air between expansion turbine stages.  The energy density of phase change materials is greater than can be stored as sensible heat.  For this to work, we simply vent the exhausted air through tubes in a tank of phase change material.  When the time comes to compress air for storage, we pass it through the same tank before it enters the compressor.

The above would be a better way of using CAES on a small scale.  We could in fact build CAES systems that store compressed air in pressure vessels.  The heat generated by compression could be used for heating and the cold generated by expansion could be used for refrigeration.  Avoidance of intercooling and interstage heating would cut a lot of the complexity and capital cost out of the process.  Although expansion would capture less than half of the input work energy, the total energy value of the output work, heat and cold, would be close to 100% of the input work value.

Different systems can be tailored to the needs of specific users.  For example, if we pass high pressure air through the chiller tank, prior to entering another compressor stage, the second compressor could generate liquid air.  This is an easier option for long term energy storage than CAES, because it can be stored as a dense liquid in an ambient pressure insulated tank.

Last edited by Calliban (2023-12-18 10:34:41)


"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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#258 2023-12-18 14:17:13

kbd512
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Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

Calliban,

The Socony-Mobil process can upgrade methanol or ethanol to gasoline using ZSM-5 zeolite-based catalysts.  I would suggest that some methanol or ethanol be mixed into the gasoline for a cleaner burn, modest octane rating increase, and the fact that all modern automotive engines have already been modified to use ethanol-gasoline blends.

I know that the temptation will always exist to chase after the next shiny new object of affection, without understanding and acceptance of why we decided to blend ethanol with gasoline.  Too much ethanol and you have very real water absorption problems without a completely sealed fuel system.  Numerous companies are having problems producing gas caps that don't fail to seal within a year, so there's a practical upper limit on the ethanol content of the fuel.  15% ethanol seems to be quite usable for all existing vehicles.

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#259 2023-12-18 15:07:09

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

If we can produce hydrogen and capture CO2, we first produce methanol and then use the Socony-Mobil reaction to produce longer chain hydrocarbons.  Everything starts with an efficient way of producing hydrogen on a large enough scale.  We do not need to be concerned with storing and transporting this hydrogen, because it will be consumed in a sabateur reaction as soon as it is made.  To make it on a large scale without fossil fuels, thermochemical processes are expected to have the lowest cost overheads.
https://en.m.wikipedia.org/wiki/Sulfur% … dine_cycle

But the the required temperatures are high - a minimum of about 800°C for the iodine-sulphur cycle.  One way of using intermittent energy to drive this cycle would be to store high heat in a tank molten sodium chloride salt.  This melts at 801°C and latent heat of melting is 520J/gram, 224kWh/m3.  The walls of the container would be lined with a material that is non-reactant with molten sodium chloride.  Pyrolytic graphite is probably the lowest cost material.  Heat exchangers would be behind the graphite wall.  The means of heating the molten salt could be electric immersion heater either within the salt or behind the graphite.  Alternatively, the salt could be heated by direct solar heat, from a focus collector and transfered to the salt by liquid sodium flowing through a heat exchanger behindd the graphite wall.  The heat source could also be direct mechanical wind power.  Wind turbines would drive hydraulic fluid, which would generate high heat by compressing air in an enclosed volume without intercooling.

The pipework and vessels used in the iodine-sulphur cycle probably need to be stainless steel.  That is costly, but sulphuric acid at 800°C is so corrosive that there aren't many materials that could stand up to it for very long.  We might get away with ceramic lined vessels and pipework if we are careful to control temperature gradients throughout operational life.  Any rapid change in temperature of the reaction vessels would result in differential thermal expansion or contraction, introducing stresses which could crack the ceramic lining.  But if we can control temperature within narrowly defined limits, we might be able to use ceramic lined carbon steels.  But it does mean that once the plant is heated to operational temperature, it is difficult to shut down and restart.  It will only have so many thermal cycles before linings are destroyed.  It is precisely because of issues like this that industry wants uninterupted power.  Outages can actually cause damage.  We can partially avoid the problem by oversizing the molten salt storage tank.  That way, if we get a week without power we can keep the plant hot and even continue making fuel at reduced capacity.

Last edited by Calliban (2023-12-18 15:31:08)


"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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#260 2023-12-18 16:34:16

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

According to Goehring & Rosencwajg, the Permian basin is expected to reach peak production in ~1 year.
https://oilprice.com/Energy/Crude-Oil/T … stors.html

Companies are running out of tire 1 acreage, with 85% of new wells being child wells of existing producing wells.  Well productivity is declining, because wells are being drilled too close together and are interfering with the pressure gradients of neighbouring wells.  When the Permian peaks, US oil production will peak with it.  That will lead to a rapid build up in oil prices and a resultant increase in refined fuel prices.  That may be the window of opportunity for developing a synthetic fuel programme.

Last edited by Calliban (2023-12-18 16:35:14)


"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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#261 2023-12-18 17:19:05

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,812

Re: Why the Green Energy Transition Won’t Happen

https://www.forbes.com/home-improvement … run-house/
https://www.energysage.com/electricity/house-watts/
https://blog.ecoflow.com/us/how-many-wa … run-house/
https://www.energysage.com/energy-stora … -how-long/


According to data from 2020, the average amount of electricity an American home uses is 10,715 kilowatt-hours (kWh). If you divide this number by 12 (months in a year), the average residential utilities customer uses 893 kWh per month.

If you divide 10,715 kWh by 365 (days in a year), you’ll get the average number of kilowatt-hours used per day, which is 29.36 kWh. If you multiply that by 1,000, you can find the energy consumption in watts that occur in 24 hours, or 29,360 watts. If you then divide that by 24, you’ll find that the average household requires 1,223 watts of power.
For example, consider that you have the following:

An air conditioner that requires 1,100 running watts and 1,700 starting watts

A refrigerator that requires 800 running watts and 2,400 starting watts
A television that requires 500 running watts and 0 starting watts
A tea kettle that requires 600 running watts and 0 starting watts
Here are a few appliances you typically see in kitchens along with how many watts they use on average:

Laptop: 50 to 100 watts
Flat screen TV: 60 to 115 watts, depending on the model, size and age.
Dishwasher: 1200 to 1500 watts
Microwave: 966 to 1723 watts
Oven: 2150 watts
Coffee Maker: 800 to 1400 watts
Refrigerator: 150 to 400 watts
Washing Machine: 500 watts
Dryer: 1,000 to 4,000 watts
Central Heating Furnace: 340 watts
Portable Electric Fan Heater: 2,000 to 3,000 watts
Central Air Conditioner: 1,000 to 4,000 watts
Window AC Unit: 900 to 1,440 watts


According to this number "29,360 watts." I normally am quite close as for my day usage.
So, the issue is for peak item use that must have the saved energy for when you need to power manage.

So, if I use a hybrid thermal sand source to make up for the extra equal to the daily value, I think that amount should cover when I need more energy for the appliances as a standby energy source.

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#262 2023-12-19 10:26:44

SpaceNut
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Posts: 28,812

Re: Why the Green Energy Transition Won’t Happen

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#263 2023-12-19 11:56:06

kbd512
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Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

SpaceNut,

Maybe the radical left should stop trying to force their climate religious beliefs on others and start coming up with more practical solutions that are both more affordable and more reasonable to implement.  Bans don't work.  Street drugs are banned, but in leftist utopia there's an epidemic of illegal drug use.  Leftists have such an insatiable appetite for remaining stoned out of their minds 24/7/365 that there's an endless supply of crack, meth, and fentanyl.  That's how dedicated they are to ruining themselves because they can't deal cards with reality.

I know this is anathema to wanna be communist dictators who wish to impose their will on other people, but that's also why free markets were created and communism utterly failed every place on Earth it's been tried.  The only ideas that the left has a functional monopoly on are stupid, crazy, and plain old evil masquerading as virtue.  Leftists do bat guano crazy and evil almost infinitely better than any other group of people on the planet.  They do not waste any energy learning to control themselves, which is what they should be focused on.

Here's a wild and crazy thought:

Until close to 100% of all existing electrical power generation is achieved without burning something, forcing people to pay for something that is less efficient than direct heating and inordinately more expensive, is dumb, crazy, and outright evil when it deprives them of what they need to survive, in addition to being utterly pointless since it completely fails to do what it purports to do, namely reducing emissions.

The right's approach is to devise products and services that people actually want to buy.  In general, over time those products are refined and are made cleaner from an emissions standpoint.  There's nothing perfect about them, but rather than fixating on pointless unachievable perfection, we choose to strive for excellence.  We make cars with 650hp V8 engines that generate less CO2 driving down the road at 70mph than horses do galloping at 40mph.  The engine is as powerful as 650 horses, but weighs a small fraction of what a single horse weighs, and since it's a block of metal it consumes far less and emits far less than a single horse.  Despite that fact, nobody on the political right thinks that horses should be banned.  In point of fact, horses still have the right of way on our streets.  However, no bans were required to convince people that the V8 is mightier than the quarter horse.  Which one was more practical and usable was self-evident to the former horse riders.

The left's approach is to force people to buy things they can't afford, to support their religion.  These products are increasingly impractical and costly, they don't actually replace anything so more and more mindless consumption is baked into their non-solutions, they cannot be recycled in any practical sense so they create literal mountains of toxic waste, and there's not enough metal on the planet, especially Copper and Lithium, to implement their ideas at a global scale.  All in all, it's a recipe for an epic failure, which seems to be the only kind of failure that the left is capable of.  Small failures taken as "teachable moments", as President Obama called them, are ignored.  They don't seem to be capable of accepting not-so-subtle hints from everyone else that their ideas don't work.  The cherry on top is the fact that they never admit to failure so they might then move towards ideas with a chance of actually working.

How beholden do you have to be to an ideology to recognize when what you're after is not even furthering your stated cause?

Electricity is not something that will ever replace combustion within our lifetimes, so pursuit of more practical alternatives needs to be part of the conversation.  It took 100 years to create the electric grid we already have, so any realistic thinking person would rightly assume that it'll take another 100 years to double or triple its capacity.  It took 100 years for cars to replace horses.  The German Army primarily used horses during WWII, not trucks.  They still use cows and horses in African or Asian countries.  At no point in time in human history has the mining capacity doubled within 10 years to extract a metal that we're already mining.  There must be a physical reason for why that is so, apart from coal / oil / gas companies preventing more electrical power from coming online.  They directly profited from that, yet there was no doubling of the electric grid's capacity in 10 years.  Progress doesn't accelerate by issuing edicts about what you may or may not use to power your daily life.  New York replaced horses with cars because there was so much horse manure on the street that you couldn't walk in the street.

Playing shell games with emissions is not "meeting emissions targets".  It's just a dumb religious-political game of hot potato, in which no actual progress is achieved, because none is possible.  People who think our current ways of doing things are "too dirty" should be forced to prove, ahead of issuing any edicts, that their proposed change is actually cleaner.  All emissions will count towards the total, regardless of where they take place, so every last drop of coal, oil, or gas must be factored into the final result.  After that analysis is performed in an open and honest way, another analysis based upon cost needs to be performed.  If we could solve all of our emissions problems tomorrow, merely by making all vehicles, power plants, and other energy consuming devices from pure Gold, that's still not a practical solution, due to the scarcity of Gold.  Money is merely a proxy for energy, materials, labor, and relative scarcity.  In a free market, cost or money puts a cap on the implementation of any non-workable solution, so that more workable solutions can take their place.  You can demand to fly in an "all-Gold airplane", but money puts a cap on who can actually do that, and to what extent, with the end result that all airplanes are made from much lighter and stronger materials, even the ones painted to look like they're made from Gold.

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#264 2023-12-20 02:39:57

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

This is an interesting ducted wind power concept that could actually hold promise for small scale and offgrid energy production.
https://www.ventumdynamics.com/industry

Smaller wind turbines are less efficient because wind speeds close to the ground are suppressed by friction with the surrounding topography.  For smaller devices, the tower represents a disproportionate share of cost and embodied materials.  This is no less the case for this design.  Both effects tend to increase energy payback time.

However, the ducting around the turbine is not a moving part.  It could be made from brick and ceramic like a chimney pot.  Such a structure could last for centuries.  Likewise, the tower could be made from brick and could contain an insulated water tank to store excess energy as heat that will later be used to heat a house.  The brick structure and tank could last centuries as well.  The lower volume of the tower could be used as a garden shed.  The parts that will need replacement are the vertical axis turbine and the generator.  These are non-trivial components, but are a small part of the overall device.  So something like this would work for powering a house, provided that the householder were prepared to make a large upfront investment for benefits that will acrue over decades.  It would also require that householders adjust demand patterns to match supply.  That will not be popular, but there isn't any way of avoiding it.  The burden can be reduced by oversizing the turbine relative to electrical loads and using additional power to heat water.

The device appears to be quiet and has no visible moving parts, with the turbine being encased in the wind duct.  This is important in European locations, where visual intrusiveness and nouse are both important considerations in granting planning approval.

Last edited by Calliban (2023-12-20 02:49:03)


"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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#265 2023-12-21 01:30:11

kbd512
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Registered: 2015-01-02
Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

Burden of proof: A comprehensive review of the feasibility of 100% renewable-electricity systems

The Great Green Energy Transition Is Impossible

...
Operation

If we pretend that Tinkerbell could sprinkle some magic pixie dust on the world's deserts and turn them to copper, or a herd of unicorns could tow an all-copper asteroid into Earth orbit, and bring it down to the Earth’s surface without opening another Chixchulub crater and wiping out 95% of land animals and plants, and we manage to build the demanded technology units, the next problem is “how do we operate an electrical supply system in which all generators use renewable sources?” In Burden of proof: A comprehensive review of the feasibility of 100% renewable-electricity systems, Renewable and Sustainable Energy Reviews 76, Elsevier (2017), pp 1122-1133, Ben Heard, Barry Brook, Tom Wigley, and Charles Bradshaw described the result of their analysis of 24 papers in refereed professional journals that claimed to explain how to do it. They evaluated them on four criteria using a weighted scoring system with a maximum possible score of seven. No paper scored more than four.

One factor that Heard et al considered is that it is necessary for a generator to put power on the grid with voltage, frequency, and phase very accurately matching the grid. Otherwise, they risk damaging their equipment, the grid, and customers' equipment. If there's no “signal” on the grid, how do they do it? The way it's done now with hundreds of large generators is that each one starts up but doesn't connect its grid to the regional grid. Then the operators get on the telephone and agree which two will be synchronized and their grids connected. Then the ones with connections to the synchronized grid can synchronize and connect, .... That's why it takes a week to restart after a regional blackout. With millions of generators instead of hundreds, the grid might not get restarted before it fails again. This problem might be solvable, for example by converting the transmission grids from AC to DC, at significant additional expense, so there are no frequency or phase synchronization problems.

Storage

Assuming the system can be built, and we learn how to operate it, the next question is “what do we do when the sun isn't shining and the wind isn't blowing?” The glib answer is Storage! but that answer is never quantified by activists. Several people have tackled the quantity question. Their answer is 400-800 watt-hours of storage per watt of average demand, assuming average generation is equal to average demand. My calculations, using twelve years of California generation data, are much more pessimistic — almost 1,500 watt hours per watt of average demand. Many people have looked at the technology of storage and concluded that the only physically feasible scheme uses batteries. Pumped storage, compressed air, flywheels, ultracapacitors, towing rocks up and down mountains or abandoned mineshafts, unicorn farts, etc. simply will not work at the necessary scale.

So how much would batteries cost? Using the most optimistic 400 watt hours requirement — something a real engineer would never do — and assuming installation is free — another thing a real engineer would never do — one might look in Tesla's catalogue and discover the price is $0.543 per watt hour — before installation — and the warranty period, roughly equal to the lifetime, is ten years. Activists insist that an all-electric American energy economy would have average demand of 1,700 gigawatts. If one evaluates the formula 1,700,000,000,000 × 400 × 0.543 / 10, the answer is $37 trillion, or about twice total USA 2020 GDP, every year, for batteries alone. Activists say build more generators so you don't need as much storage! Read the Materials section again.

Of course, even with 1,500 hours of storage, today's industrial economy will not survive with an all-renewable energy system the next time Mount Tambora erupts and gives the Earth another “year without a summer” as in 1816 — and it will happen.

Emission-free Vehicles

One proposition, endorsed by California Governor Newsom, is that no hydrocarbon-powered light vehicles will be sold in California after 2035. Of course, this edict is illegal without legislative action — it came from the unelected California Air Resources Board, not the legislature.

The argument is that the vehicles are emission free. But that's only at the point of operation, not a life-cycle analysis. They export emissions from rich neighborhoods where people can afford electric cars, to poor neighborhoods, such as around the coal-fired generators on the Navajo and Hopi reservations, so that poor people can enjoy the emissions instead, and tourists can't see the bottom of the Grand Canyon. Moreover, a study published by the Ifo Institute of Germany in 2019 found that an electric Tesla Model 3 emits 11% to 28% more CO2 over its lifespan than a diesel Mercedes C220D. Life-cycle analyses are subject to uncertainty, and no single study is an end-all, but this clearly proves that electric vehicles are far from emission-free.

Electric vehicles are 25% heavier than hydrocarbon-powered ones, on average, so they require more energy and produce more carcinogenic particulate emissions in the form of tire and brake dust, road damage, and stirred-up road dust. Road damage doesn’t increase in proportion to vehicle weight. It increases in proportion to the fourth power of the axle weight, so an EV ought to pay 2.4 times more road tax per mile. But they don't pay anything into the highway maintenance fund that everybody else pays into at the gas pump. So they're another subsidy that rich people use to display their virtue. And when they catch fire, you can't put them out.

Why Do It?

At this point, one wonders “Why spend so much time, effort, and money on impossible schemes that damage the environment?” As Michael Shellenberger asks “Must we destroy the environment to save the planet?”

Another glib answer is because we have to do it! But why do we have to do it? To reduce carbon dioxide emissions, because they cause climate change. Notwithstanding what journalists and politicians and lawyers and architects and gynecologists and theologians and liberal arts professors at universities and ... insist, there is no cast-in-stone scientific consensus that human activity is in fact changing the climate, and that if it were that it would be harmful. Science is never “settled” if you're actually a scientist or understand science. The essence of science is skepticism.

The social reality is that journalists and other bullies have convinced the public of the “truth” of anthropogenic climate change and the immediate need to do something! about it.
...

And there it is...  Uneducated bullies pushing an anti-humanist climate religion that hates science whenever it involves basic math, because they're mathematically illiterate when it comes to the energy and material economics of what they propose.

He goes on to state in the article that if we never mined another gram of fresh Uranium, the United States has enough Uranium, if it used electrical reprocessing, to supply 100% of the energy for an all-electric future, for the next 582 years.  Add the Thorium we have coming out the ying yang and we have enough energy, even if we mindlessly focus on electrical energy the way the evil clown climate religion does, for another 2,328 years, for a grand total of 2,910 years.  Since there's about 1,000,000 times more Uranium in the ocean than can be mined on land, there's about enough Uranium and Thorium to provide 100% of the total global demand until the Sun is projected to go super nova and incinerate the Earth.  The climate changers will then have an actual point to make, not that any amount of CO2 or lack of CO2 will matter in the slightest at that point.

Plentiful Energy: The Story of the Integral Fast Reactor

The people who believe in this wind turbine and photovoltaic cell nonsense are monumentally ignorant of the amount of metal that the Earth can actually provide.  If this "green energy" idea is as important as they assert it is, then they need to find another way.  Calliban and myself have busily concocted viable mechanical wind turbine, solar thermal, and nuclear thermal solutions, as well as more practical energy storage options, because we both know that eventually the hydrocarbon fuel will run out.  At the end of the day, an all-electric future doesn't happen without an all-nuclear future.

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#266 2023-12-21 02:11:29

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

Beyond Force: A Realist Pathway Through the Green Transition

Trying to force adoption of clean energy with subsidies, regulations, and exhortations will fail. The only realistic way to spur the green transition is to develop clean technologies that can reach effective price and performance parity with dirty ones. Then markets will adopt them at scale.

More "simple truth" from Van Snyder:
Adequate Storage for Renewable Energy is Not Possible

Activists insist that an all-electric United States energy economy would have average demand of about 1.7 TWe. Assume California average generating conditions from 2015 through 2022 apply to the entire nation, and therefore 2876 watt hours of storage per watt of average demand is adequate (this is optimistic). The total cost for Tesla PowerWall 2 storage units, not including installation, with 2876 × 1.7 terawatts = 4.89 quadrillion watt hours' capacity would be 4.89 quadrillion × $0.543 = $2.66 quadrillion, or about 133 times total US 2018 GDP (about $20 trillion). Assuming batteries last ten years (the Tesla warranty period), the cost per year would be 13.3 times total US 2018 GDP. The cost for each of America's 128 million households would be about $2,075,000 per month. This analysis assumes 100% battery charge and discharge efficiency. They're closer to 90% (81% round-trip), so the necessary capacity and cost would be about 25% more.

How many of us can afford to pay 2 million dollars per month to store enough electricity to make this all-electric dream work?

Print more money, right?

Bidenomics only works until you run out of other peoples' money.

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#267 2023-12-21 05:32:49

Terraformer
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From: Ceres
Registered: 2007-08-27
Posts: 3,811
Website

Re: Why the Green Energy Transition Won’t Happen

Many people have looked at the technology of storage and concluded that the only physically feasible scheme uses batteries. Pumped storage, compressed air, flywheels, ultracapacitors, towing rocks up and down mountains or abandoned mineshafts, unicorn farts, etc. simply will not work at the necessary scale.

What is their argument for this, that we don't have enough concrete and steel and will have to use lithium instead?


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#268 2023-12-21 15:45:44

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

Terraformer wrote:

Many people have looked at the technology of storage and concluded that the only physically feasible scheme uses batteries. Pumped storage, compressed air, flywheels, ultracapacitors, towing rocks up and down mountains or abandoned mineshafts, unicorn farts, etc. simply will not work at the necessary scale.

What is their argument for this, that we don't have enough concrete and steel and will have to use lithium instead?

Batteries are operationally simple.  No moving parts and minimal active management aside from occasionally adding water.  And if you want to store 1kWh of electricity, you aren't going to be fooling around with pumped hydro or compressed air.  And there are situations where batteries are the best technology.  No one wants and compressed air powered hearing aid and those wind up dynamo torches are tiresome.  But powering a whole city with batteries would have sounded like a stupid idea twenty years ago.  Batteries got cheaper in money terms when they started making them in China.  That seemed to lull everyone into a false sense of security.

Last edited by Calliban (2023-12-21 16:06:10)


"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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#269 2023-12-21 21:05:15

kbd512
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Registered: 2015-01-02
Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

Terraformer,

There is no fact-based analysis on heat and pressure energy generation and storage systems.  The argument against energy generation and storage using heat / pressure and common materials is essentially limited to its viability for producing electricity.  That is the only thing they're considering, because they're fixated on it.  Practical systems were considered "inefficient" for the purpose of generating electricity, which is true, yet no truer than if using photvoltaics and wind turbines to generate electricity, so it was immediately discarded as a potential solution, without consideration given to all the inefficiencies associated with generating and storing electricity using intermittent sources.

The magical thinking was that we'd discover some new bit of electrical or electronic technology that would overcome those otherwise insurmountable specialty metal requirements associated with electrification.  We've had home photovoltaic systems since I was a child, but the economics of powering human civilization using them hasn't changed one little bit.  Even if modern incarnations were 100% efficient, the economics wouldn't change, because the material inputs haven't changed.  We've become a lot faster at mass manufacturing complex machines using robotics and process automation, but that's about it.  That's a form of efficiency, but very far from the most important one.  The process of converting Silica into Silicon wafers hasn't changed, and that's the most energy intensive part.  The tech and materials to dope and transform Silicon into microchips would be almost unrecognizable today, when compared to what existed 40 years ago, but that primarily applies to computing rather than to photovoltaic cells.

Computer chips have increased their compute efficiency by multiple orders of magnitude since they were invented.  No such performance increase has happened for photovoltaic cells over that same timeframe.  Roughly speaking, the simplest / lowest embodied energy single junction monocrystalline cells were about 25% efficient 40 years ago when they were invented for the space program, and the same remains true today.  I want to say our panels had a 26.5% BOL efficiency, and the neighbor's panels from when I was a small child were about 25% efficient, if I remember correctly.  In relative terms we both spent about the same amount of money for the same amount of utility.  If you are willing to spend piles of additional money and energy to fabricate voltage-matched triple-junction cells, then BOL conversion efficiency can increase to about 40%.  That's definitely significant and meaningful, but hardly a game changer.  Yes, I'd much rather have 40% efficient panels on my roof, but not for $1,000,000/kW.  If you have that type of money, you can go online right now and there are multiple companies who will deliver the goods.  Understandably, all of their present customers use them to power satellites.

We have advanced simulation software available today that can optimize very large wind turbine blades and electric motor-generators, but the efficiency of both is rapidly approaching absolute limits.  Here again, people tend to conflate what a computer can do with what an energy generating device can do.  When your propeller blades are already 85% to 90% efficient for their design operating conditions and your motor-generators are 95% efficient, how much additional money should be invested into making the nth copy a fraction of a percentage point more efficient?  Is a 1% performance improvement worth spending twice as much money on the device?  The 2MW to 3MW motor-generator is still the size of a small shipping container, the blades are still longer than the largest airliner wings, the blades are still constantly resisting forces that would instantly destroy the strongest fighter jet wings, and there are no real "tricks" available to dramatically reduce material inputs or dramatically increase blade lifespan.

Calliban, myself, you, and some others have done enough back-of-the-envelope calculations to show that thermal and pressure based systems can work if we decide to implement them at scale, because they don't require electrical or electronic technology that doesn't exist, quantities of specialty metals that don't exist here on Earth, or any other miracles of science / religion / philosophy.  This is what you'd do if you were only after the stated result of reducing emissions, and were completely agnostic about how it was achieved.

I've seen no scientific explanation as to why 5% of the total global steel output, over the next 20 years, couldn't be devoted to thermal and pressure based energy generation and storage systems.  Low grade heat and pressure represents 75% of the energy we presently use.  With appropriate appliances and vehicles, it could be up to 90% of the energy we use.  Fuel use would be limited to aircraft or ships.  That would be the start of a very different world, one that truly is more sustainable because it's not based on planned obsolescence, less driven by mindless consumerism, and hopefully more focused on people, who actually matter.  We are not left wanting for energy or materials to make that happen, merely the willingness to let go of a heavy sinking object, before it drowns us.  I think electric and electronic technology will remain quite useful, as it always has been, but it's not a long-term viable means to power humanity.  Electricity is merely one aspect of a much more comprehensive solution set.  We can't continue to ignore the other parts.

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#270 2023-12-22 05:26:05

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,811
Website

Re: Why the Green Energy Transition Won’t Happen

Calliban,

This is in the context of grid storage though. The mobility advantages of batteries don't apply to that.

There's supposed to be a 250MWh liquid air energy storage plant being built in Manchester at the moment. No idea how it's progressing. 60-70% round trip efficiency puts it on par with hydrogen, but with less nightmarish storage requirements because nitrogen and oxygen find it harder to diffuse through the containers they're in? I wonder how well this would combine with solar thermal to provide the reheating energy...


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#271 2023-12-23 13:25:55

kbd512
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Registered: 2015-01-02
Posts: 7,410

Re: Why the Green Energy Transition Won’t Happen

I want to use an example to illustrate how and why electrical systems can be so wasteful of energy, but I'm going to do it using Aluminum recycling, or lack thereof, as our prima facie example.

The US EPA posted on their website that approximately 6,440,000,000lbs or 2,921,138,337kg of Aluminum was dumped into US landfills during 2018.  Useful metal aside, what that truly represents is a staggering amount of energy that will be required the next year to make more soda cans, engines, and high voltage power lines.

Approximately 17,000kWh or 17MWh of electrical energy per metric ton of Aluminum is required to mine raw ore to convert that material into usable metal.  This is certainly not all of the energy consumed, just the electrical energy consumed.  It's the lion's share of the energy input, so it's a "good enough for government work" proxy.

2,921,138t * 17,000,000Wh = 49,659,346,000,000Wh of energy input, primarily electrical energy.

50GWh of energy is the functional energy generation equivalent of six 1GWe nuclear reactors doing what they do best, for an entire year.

Professor Michaux has stated that we would need approximately 8 billion metric tons of Copper to provide enough electrical conductor metal to replace the current energy system with a 70% wind and photovoltaic energy system.  Since we can't get that amount of Copper, irrespective of money and energy input, we're going to use Aluminum as our viable alternative.  That means 4 billion metric tons of Aluminum for equal electrical resistance, assuming that electrical resistance is the only material property that matters.

4,000,000,000t of Aluminum * 17,000,000Wh/t = 68,000,000,000,000,000Wh of energy

68,000,000,000,000,000Wh / 8,760,000,000,000Wh = total annual electrical output of 7,763 1GWe nuclear reactors

Divide that total power requirement figure by 20 and you still end up with a requirement for 388 new gigawatt-class nuclear reactors.

As of May 2023, there were 436 nuclear reactors in operation in 32 countries around the world. The United States had the largest number of nuclear power reactors in operation at the time, at 93 units. Operable nuclear reactors are those connected to the grid.

Assume that all the power from those reactors is already spoken for, because it is.  That's why they were built in the first place.  They weren't created to showcase the glory of the atom.  We typically demand that things we build do something useful for us.

1. Does it seem reasonable to anyone else to construct another 388 gigawatt-class nuclear reactors, solely to smelt Aluminum for the next 20 years?

2. If we're not going to build 388 new reactors, then where in the Sam Hill is all that additional power coming from to make that much Aluminum?

3. Is it going to come from wind turbines and photovoltaics which need that Aluminum metal input in order to be built and connected to the electrical grid?

4. Is it more probable that the required energy will come from burning through absolutely insane quantities of coal, oil, and gas?

I'm guessing that we're going to answer that series of questions by selecting Option #4, just as China and India already have, unless we all get behind nuclear power, which doesn't appear to be happening.  Here we are, and we've only defined the energy input requirement for one of at least a dozen monumentally large metal demands to construct this "green dream alternate reality".  Old King Coal it is.

68,000,000,000,000,000Wh / 2,200,000Wh per metric ton of coal = 30,909,090,909t of coal

That is 1,545,454,545t of coal per year, for the next 20 years...

The entire world consumed 7,767,181,642t of coal per year.

We're going to increase our total global coal consumption by another 20%, for the next 20 years, merely to create the required tonnage of electrical conductor metal.  In our quest for "green energy", we're going to burn through even more coal than we presently do.  All of our purported emissions reductions benefits will be completely erased by the requirement for conductor wire alone.

If we burn through 20% more coal than we presently do, will our CO2 emissions go up or down?

As we bring more and more "green energy" onto the grid, is it at least "less puzzling "to everyone else as to why our emissions continuously increase, year-over-year?

In 20 years time, it'll then be time to replace 5% of those aging wind turbines, photovoltaics, and electro-chemical battery energy storage subsystems.  Short of a technological miracle, we'll remain on that energy sink treadmill ever after.  5% of all energy will be devoted to completely recycling what we've already built.  That process will never end, because it can't unless we finally pull the plug on this unworkable idea.

Can anyone else besides Calliban or myself figure out why electrification is not a "silver bullet" solution for reducing emissions?

It's almost as if it was never meant to be.

This seems like a minor quibble at this point, but the required annual production rate of 200,000,000t of Aluminum per year, represents just shy of 3 years of global 2022 Aluminum production levels, which was 69,000,000t, squeezed into each year, over the next 20 years.  Do we have enough Aluminum ore?  Well, yes.  Aluminum is quite abundant here on Earth.  It's the second most common metal in the Earth's crust, after Silicon.  It's relative abundance says nothing about the ease with which it can be converted into metal, though.

Fight basic energy and materials scarcity physics all you want.  In the end, physics always wins.  No other outcome is possible, if this is the cart we're tying our horses to.  The quantity of Aluminum conductor to account for wind turbines / photovoltaics / grid storage / electric vehicles, if produced as a substitute for Copper we physically don't have on Earth, would require operating an additional 388 nuclear rectors at full output over the next 20 years, or increasing total global coal consumption by 20%.  Anyone who thinks "green energy transition" means we run things more or less as we do, with modestly expanded grid output, is delusional.  I don't care what degree they have or what they claim in an internet video.

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#272 2023-12-23 18:29:03

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

Looking at the material requirements for both Wind and Solar PV.
https://www.energy.gov/sites/prod/files … pter10.pdf

Wind power is by far the better of the two.  Wind power requires 35 tonnes of aluminium per TWh.  For Solar PV, the figure is 680 tonne per TWh.  The energy cost of aluminium was 20kWh/kg, last time I checked.  If anything, 17kWh/kg is optimistic.  Taking the 20kWh figure, the energy cost of 35t Al is 0.7GWh, or 0.0007TWh.  The energy cost of 680t Al is 13.6GWh.  All on its own, the aluminium required to produce 1TWh of PV electricity eats up 1.36% of that electricity.

The copper needed for 1TWh of wind and solar generation are 23t and 850t, respectively.  The latter figure is ckearly problematic.  Of course, these examples are only relevant to PV Solar and wind-electric.  They don't tell us anything about the materials needed by solar thermal generators.  There are also a lot of other options for wind power, which we have discussed before.  One involves using turbines to pump hydraulic fluid and then usining hydraulucs to power a centralised generating station on the ground.

I don't think any of the Department of Energy figures account for any energy storage in calculating materials budgets.  If we were able to adapt the fact that wind electricity is only intermittently available, then a wind based electricity system could have favourable energetics at least in some places.  But as we have discussed before, living with intermittent energy would be a very different way of life to what most of us are used to.  I think after a few months of working long and unpredictable hours, most people would lose patience with intermittent energy.

Last edited by Calliban (2023-12-23 18:46:00)


"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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#273 2023-12-24 15:19:24

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,812

Re: Why the Green Energy Transition Won’t Happen

The issue is the large number favor the power producing companies that are just providing to make bigger and bigger profits and not to help the nation or its people.
Gasoline is now below $3 currently but has a long way to go to promote the economy for the poor to be able to have what they are going without. The same holds true with the current deregulated price for a kwhr of energy.

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#274 2023-12-24 18:32:49

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,396

Re: Why the Green Energy Transition Won’t Happen

The Integral Fast Reactor was fully developed by the early 1990s.  The only technology that hadn't been demonstrated at scale was the pyroprocessing of spent fuel.  This involved melting the U-Pu-Zr-fissium alloy in a bath of liquid cadmium.  Fission products dissolved into the cadmium, actinides seperated by gravity.  This has since been shown to work, but no one has developed the idea at scale because funding has been absent.

Fast reactors are the most resource efficient solution for production of electric power and direct heat.  The systems involved have extremely high power density, which allows for extremely compact powerplants.  A fast reactor core with metallic fuel, has power density up to about 500MWth/m3.  Compare that to the ~1kW/m2 intensity of sunlight in the worlds hottest deserts at noon time.  The primary circuit of a powerplant capable of powering a city of 1 million, would be not much bigger than a 4 bedroom house.  It is hard to imagine any other system that beats that performance.  And newly designed nuclear powerplants last a century.  That means that a stainless steel machine the size of a house, can power a large city for a century.  There really aren't any resource limitations that prevent a fast reactor economy from being realised.  The problems are institutional.  There are a lot people that really don't want this to work.

A lot of the renewable energy based systems that Kbd512 and I have examined, are designed to be technologically simple, long-lived and made from low energy or easily recyclable materials.  The reason is simple.  Renewable energy sources are diffuse and have weak power density.  The only ways of achieving a decent net energy return on investment, are to either limit embodied energy or make the systems involved long lived.  Embodied energy can be minimised by using simple and abundant structural materials, like structural steels, concrete, soil, sand and rock.  Avoiding energy storage is important as well, because this often involves a greater energy investment to build than the energy source itself.  So the best option for EROI is to adjust work rate according to the energy supply available.  Longevity can be is easier to achieve in compressive structures that aren't vulnerable to rotting or corrosion.

The link below tracks the output of wind power generation for the entire UK grid over an annual period.
https://gridwatch.co.uk/Wind

It is highly variable, with peaks as high as 15GWe then crashing as low as 2GWe within hours.  If we are to live off of wind energy, we must find a way of dealing with this problem.

Last edited by Calliban (2023-12-24 19:12:44)


"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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#275 2023-12-25 07:19:15

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,811
Website

Re: Why the Green Energy Transition Won’t Happen

Re. compressed/liquid air energy storage, the latent heat of fusion in water might be usable to provide most of the heat? Yes the exhaust will be at 0c, but that's not all that bad... and the process is simple to reverse even with lukewarm heat. Which could be from the compression, or from a simple flat plate collector. It's a very simple heat storage system that won't need much insulation around it smile

If the heat for expansion is free, how does that change the roudtrip efficiency?


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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