[MonteQuest]

Do you know of a bio fuel with a high carbon content that will produce 1300 degrees F?

You are kidding right? I mean dry wood with a simple bellows will give you 1700 F, and you can get 2800 with dry wood or charcole or antharacite or coke in a blast furnace.

When I wrote my intial post, I did some research.

And while charcoal easily created the heat required to melt tin and copper for bronze, and to smelt pig iron, the production of higher quality iron and steel required much higher temperatures. In the early l8th century, a significant breakthrough came when pig iron was successfully smelted using coke made from coal.

I was lead to believe that charcoal would not produce the temperatures. I've conceded that I had some things wrong.

[Tanada]

Sorry Monte, this is no longer the case.

Ah yes, the combined cycle is more efficient, but not as efficient as using the NG at home to directly heat your water which was my point.

Fossil fuels can be used directly and are highly portable while alternatives must be converted to a usable form to match our infrastructure.

Back to energy density. You can't beat the fossil fuel "bang for the buck."

For this purpose I will agree, however I would be interested in seeing the tradeoff for using a desuper heat water heater on an electric heat pump for the summer, and a heat pump direct water heater for the winter. The desuperheater basically gets you free hot water because it receives the heat gathered by the cooling cycle on the heat pump central HVAC, the heat pump water heater is 2 to 3 times as efficient as an electric induction heating element but takes twice as long to heat cold water as a standard electric water heater.

Or you could always just install a solar water heater and ignore the whole problem

[Tanada]

Making Uranium metal out of ore is basic chemistry, well understood by 1900, 1920 at the latest. Making a pile of natural Uranium get hot to make steam requires high math, but not high technology. The USA did it with math and carbon blocks in 1942, without fossil carbon fuels it might have taken another 100 years, but probably not because a lot of people would be motivated to find an alternative to burning biomass.

Yes, like I just said, we would have seen peak wood first.

I agreed with you, I know it is a long post but I think I demonstrated that peak wood <tm> would have slowed technological development, not killed it dead in its tracks.

[MonteQuest]

From my initial post edit:

If we don't save a significant amount of our fossil fuels (this includes the tar sands and oil shales)for the maintenance of our infrastructure, rather than burn them up trying to meet our energy demand, where will the replacements come from? A Star Trek replicator?

We have trillions of barrels of oil shale and tar sands, you say.

So? We had trillions of barrels of oil and trillions of tons of coal at one time, but we managed to "burn" through half of them in about 150 years.

From Chevron:

It took us 125 years to use the first trillion barrels of oil.

We’ll use the next trillion in 30.

http://www.willyoujoinus.com/advertising/print/

We don't have a lot of time to find replacements do we?

Why are we continuing to build surburbia when the writing is on the wall?

[Tanada]

From my initial post edit:

If we don't save a significant amount of our fossil fuels (this includes the tar sands and oil shales)for the maintenance of our infrastructure, rather than burn them up trying to meet our energy demand, where will the replacements come from? A Star Trek replicator?

We have trillions of barrels of oil shale and tar sands, you say.

So? We had trillions of barrels of oil and trillions of tons of coal at one time, but we managed to "burn" through half of them in about 150 years.

From Chevron:

It took us 125 years to use the first trillion barrels of oil.

We’ll use the next trillion in 30.

http://www.willyoujoinus.com/advertising/print/

We don't have a lot of time to find replacements do we?

Why are we continuing to build surburbia when the writing is on the wall?

#1, we don't have a lot of time, but I beleive we do have enough if we can get the pollitical leadership off the dime.

#2, because city planners like all polliticians are short sited and think mostly about how they can get the most tax money from the populus. The easiest way to do that is to promote higher end mcmansions which garner much higher property taxes for the local city/school district to spend. They are not interested in how to get the most tax money over time, if they were the cities would not have created tax structures that encouraged bussinesses and their employees to move to suburbia. Then the city government cries for lost revenue and boosts taxes further, which reinforces the cycle over and over until it hit equelibrium. Look at Toledo and Detroit, the two major cities closest to me. They have been loosing population for generations because of bad tax policy. If any city in the midwest or east would adopt a sain sustainable tax policy you would see bussiness and their employees flood back in because of all the benefits of living in a large city, as oppossed to leaving because of the detrimental aspects.

[bobcousins]

This thread is very interesting, but surely the pertinent question is what will the world be like after fossil fuels?

Trying to rewrite history based on a linear interpretation of events is nigh impossible, as Tanada has illustrated. While technological innovations are usually the product of necessity, scientific discoveries are as much dependent on accidents or the unpredictable spark of genius as on directed research efforts.

While it can be argued that the development of coked coal kicked off the industrial revolution, there are things that point the other direction. For example, the industrial revolution got under way with water power, not steam power. Steam engines used for pumping in mines were developed into engines that could be used for powering mills, and subsequently, rail transport. But I believe the initial event was the idea of mass production - moving cottage-level production into industrial centres. This is as much to do with social and economic engineering as technology. The key thing here is achieving economies of scale. Having machines made from plentiful iron enabled this.

I would argue that the seeds of the industrial revolution were sown with Newton, and the concept of a clockwork universe. When you have the understanding that the universe is like a machine which has known laws, then you are in a position to industrialise any process, including society. This creates the conditions for an industrial revolution, waiting for the right opportunity, whether that is provided by fossil fuels or biofuels.

Whether we would have got to where we are merely by using biofuels is a moot point, but surely unknowable? Saying that peak wood would have prevented it is too simplistic.

But instead of winding the clock back, we have a different problem. We have a post-fossil world, but we also have a body of scientific knowledge that did not exist before. That science does not necessarily disappear post peak. This means we can direct our efforts - we understand the chemistry of iron smelting for example. We don't have to randomly try burning different rocks until we find what works.

The other key point I would make is that if you use scaffolding to construct a building, after you remove the scaffold the building still stands. If we can construct an alternative energy system, the fact that it was built with fossil fuels does not matter. There is not a problem in principle.

I grant there is a major question about putting it into practice. The issues of cost, scalability and timescale are crucial. We know from Tainter that there is a level at which it simply becomes too expensive to maintain the system. Once you can no longer maintain economies of scale, the system will quickly unravel. The problem we have is that we do not know what the critical level is. Maybe the barrier to further progress will be met at fossil fuels, maybe it is nuclear fission, maybe it will be fusion, maybe something else (mining asteroids?).

We also have something that previous civilisations did not, which is a sophisticated economic system. The Romans did not particularly bother with budgets. If they wanted to know how much money they had, they looked in the vault. If they need more, they sent an army off to conquer somewhere. History shows if governments try to maintain the system, they screw up. If allowed to work, the much maligned market system may be the thing that finds alternatives. There are clearly limits to the market system, the alternatives may be uneconomic or simply not there. But it is an additional tool in our toolbox.

While we are following the previous pattern of unsustainable growth and resource exhaustion of previous civilisations, there are several advantages we have this time around. Whether these prove to be sufficient we will only find out by trying.

[Daryl]

Interesting historical points. Just wanted to add a tidbit. I forget where I read this, but someone once argued that the seeds of Western technical expertise were in Western European monasteries. This was the first time in history that the educated class performed its own manual labor. Thus it was the first time the the best brainpower focussed on how to make manual labor easier.

[bobcousins]

Interesting historical points. Just wanted to add a tidbit. I forget where I read this, but someone once argued that the seeds of Western technical expertise were in Western European monasteries. This was the first time in history that the educated class performed its own manual labor. Thus it was the first time the the best brainpower focussed on how to make manual labor easier.

Sorry dude, that doesn't square. Monks saw manual labor as a way to God, it was not a chore, it was a good thing. Although it is true they also took to more intellectual pursuits when they got rich enough to pay staff.

The reasons for replacing people with machines was to make more money, by increasing profit margin, which was the primary interest of wealthy traders. Cottage level producers did not have the capital to create factories. Traders did, and by doing so they increase their profit margins. The same thing happens today, large retailers create own brand products, small suppliers are squeezed out.

[MonteQuest]

Having said all that, there is an intrinsic limit on how much carbon you can harvest from bio-fuel sources and convert into coke to run your blast furnaces, that in and of itself would have slowed development of things like transcontinental rail roads in the USA, and technology today would be far lower than it is. That doesn't mean we wouldn't have technology, or the ability to discover radiation and fission.

No, but think of how much wood it would have taken to make the steel for the Golden Gate Bridge or an aircraft carrier. We would have gone through wood quite rapidily, as we were already doing so in many parts of the world.

It would be a much simpler world, and I think that is where we are headed when they get scarce and prohibitively expensive to use.

I found this:

How biomass could work in the iron and steel industry.

Worldwide, coke-based steel production is the dominant mode of production because of the large quantities of steel required by modern society, but charcoal use is increasing worldwide as living standards rise and urbanization occurs, especially in Africa.

Although charcoal is free of impurities and coal has to be converted into
coke, an expensive operation, the scale of production in large coke blastfurnaces has advantages.

Link

It would seem that charcoal from wood was, and is, just not scalable to meet the demands of industrial growth like coal.

While wood is renewable, it can' t be used faster than it grows!

[Tanada]

Having said all that, there is an intrinsic limit on how much carbon you can harvest from bio-fuel sources and convert into coke to run your blast furnaces, that in and of itself would have slowed development of things like transcontinental rail roads in the USA, and technology today would be far lower than it is. That doesn't mean we wouldn't have technology, or the ability to discover radiation and fission.

No, but think of how much wood it would have taken to make the steel for the Golden Gate Bridge or an aircraft carrier. We would have gone through wood quite rapidily, as we were already doing so in many parts of the world.

It would be a much simpler world, and I think that is where we are headed when they get scarce and prohibitively expensive to use.

I found this:

How biomass could work in the iron and steel industry.

Worldwide, coke-based steel production is the dominant mode of production because of the large quantities of steel required by modern society, but charcoal use is increasing worldwide as living standards rise and urbanization occurs, especially in Africa.

Although charcoal is free of impurities and coal has to be converted into
coke, an expensive operation, the scale of production in large coke blastfurnaces has advantages.

Link

It would seem that charcoal from wood was, and is, just not scalable to meet the demands of industrial growth like coal.

While wood is renewable, it can' t be used faster than it grows!

Monte, I don't get it. You admonished people to make this thread about the past so I very carefully did that with a non petro carbon scenario demonstrating how wood growth rates would have slowed, but not stopped, industrialization. You keep pulling things out of the oil rich world and saying

but think of how much wood it would have taken to make the steel for the Golden Gate Bridge or an aircraft carrier

when in my scenario there ARE no large steel ships and no large steel span bridges designed for cars. If you want to argue against my scenario you have to stick to things in the scenario or reasonable to the scenario. I stated flat out several times in this thread that until Fission became availible at date unknown that wood/charcole would be a limiting factor on how many steam plants could be built.

I also pointed out things you seem to be skipping over, iron/steel for things like wagon wheel tires would still be around, but would be cost prohibitive for mass produced things like railroad rails. You could probably afford a simple ethanol burning engine like the little low power one on a Model T ford, but you would have to put it on a wooden car because an all metal car would be too expensive for mass production. This alone limits the number of cars because there is a natural limit to how fast wood can be grown and it is already being used for home heating and cooking, metal smelting and refining, and steam plant fuel. In all likelyhood someone would have come up with a wood fuel alternative like alfalfa hay, it doesn't depleate the soil, you can cut it three times a year, and if you smash it in a hydraulic press you can make artificial wood pellets out of it. A nice cash crop in a non petro carbon world that is totally renewable long term.

So in a world without mass quantities of cars or railroads why do you need the golden gate bridge? The Golden Gate Bridge was built to make early suburbia possible, without private cars it simply would not have been built.

In a world without steel sailing ships or airplanes why do you need an aircraft carrier made of steel? Wooden sailing ships would be the rule at sea, just as they were from 1000 BC until 1890 AD. You might have a few rare metal clad military sailing ships, but limited as they are to sail power they won't be fast. A few steam powered military iron clads might guard your ports like in the American Civil War, but they would sit in port 95% of the time because it would cost too much to sail around burning valuable charcole if you were not at war, and their range would be very limited.

The other thing to keep in mind is over the course of history most of the iron made with wood or charcole in my scenario would still exist, 85% or so of the iron reduced to metal from ore would stay in use for generations. Eventually a plow wears too thin because of the abrasion of the soil, but you can use it for 50 years before that happens and you get 50% of the metal back when you recycle it. For fasteners nails and bolts would be an occasional use instead of the main method like we use today, all those fancy wooden joins created by carpenters were a way of avoiding the use of metal in the first place, with expensive metal they would still be the rule rather than the exception. Scrap cars of the very rich would be a wooden contraption with steel reinforcing where needed but most of the metal would be the engine and drive train, about 50% as much metal as a modern car, and when the car died it would all be recycled.

Monte, personal observation not criticism. You seem like a nice guy with a deep concern for the future of the human race, but I think you sorely lack the historical depth to understand how we got where we are. This causes you to see the world only as it has been during your lifetime and limits your abillity to see it existing without the cheap oil which you have experienced. We clawed our way up from campfires and stone tools all the way to water and wind mills without petroleum carbon sources. We now have billions of tons of refined metals sitting all over the landscape made with cheap petro carbon resources, but easily availible for recycle in a low growth/no growth post petro carbon world. You bring up the rule of 70 and the limits of exponential growth, but you can't see that human population growth rate has been declining for 40 years and is now projected to stabilize or slowly decline after 2050 AD. You finally research iron and steel making and then try and argue the same point I already made several times as if I were on the other side of that issue.

Make no mistake, I think we are in for some very tough times as we adjust to a world where cheap oil is no longer the primary energy supply, and cheap money finally collapses. But if you read through human history you would know that inflationary fiat money goes through cycles like this every time it is tried, it is based on compound interest and compound inflation and like all exponential systems it hits a point of no return and collapses sooner or later.

[MonteQuest]

Monte, I don't get it. You admonished people to make this thread about the past so I very carefully did that with a non petro carbon scenario demonstrating how wood growth rates would have slowed, but not stopped, industrialization. You keep pulling things out of the oil rich world and saying

but think of how much wood it would have taken to make the steel for the Golden Gate Bridge or an aircraft carrier

when in my scenario there ARE no large steel ships and no large steel span bridges designed for cars. If you want to argue against my scenario you have to stick to things in the scenario or reasonable to the scenario.

I'm not arguing against your scenario, I'm just making the observation that even if we had been able to develop technology to the same level without fossil fuels, we would have been limited in scale by the availability of a sustainable energy source if we had relied upon biomass. This is about the past; how much technology would we have developed without fossil fuels? Many people assume that all tech today would be possible. We would just have found other ways. Yes, but on a limited scale.

Sorry if you felt I was challenging your take, I was not. Just reflecting on it.

In all likelyhood someone would have come up with a wood fuel alternative like alfalfa hay, it doesn't depleate the soil, you can cut it three times a year, and if you smash it in a hydraulic press you can make artificial wood pellets out of it. A nice cash crop in a non petro carbon world that is totally renewable long term.

Not on a scale that would exceed wood production or that would exceed the EROEI of wood.

So in a world without mass quantities of cars or railroads why do you need the golden gate bridge? The Golden Gate Bridge was built to make early suburbia possible, without private cars it simply would not have been built. In a world without steel sailing ships or airplanes why do you need an aircraft carrier made of steel?

These were examples of large scale steel technology that just wouldn't have been possible is all the point I was making.

The other thing to keep in mind is over the course of history most of the iron made with wood or charcole in my scenario would still exist, 85% or so of the iron reduced to metal from ore would stay in use for generations. Eventually a plow wears too thin because of the abrasion of the soil, but you can use it for 50 years before that happens and you get 50% of the metal back when you recycle it.

Kinda limits the future of our infrastructure to short-term doesn't it?

Monte, personal observation not criticism. You seem like a nice guy with a deep concern for the future of the human race, but I think you sorely lack the historical depth to understand how we got where we are. This causes you to see the world only as it has been during your lifetime and limits your abillity to see it existing without the cheap oil which you have experienced. We clawed our way up from campfires and stone tools all the way to water and wind mills without petroleum carbon sources. We now have billions of tons of refined metals sitting all over the landscape made with cheap petro carbon resources, but easily availible for recycle in a low growth/no growth post petro carbon world. You bring up the rule of 70 and the limits of exponential growth, but you can't see that human population growth rate has been declining for 40 years and is now projected to stabilize or slowly decline after 2050 AD.

I care to differ. Sure, we clawed our way up, but the total population of the world has remained essentially constant for most of the history of mankind. World population fluctuated between 10 million and 300 million for most of the last 10,000 years, never reaching 1 billion until about 1850. We now have 6.5 billion. Big difference.

We may have billions of tons of refined metals that we can recycle, but we also have the 6.5 billion people and the infrastructure to support them that requires a huge infusion of energy to maintain. We cannot afford it now with fossil fuels.

Human population growth rate has been declining for a plethora of reasons, one of which is that the carrying capacity has been exceeded.

In 2050, we will have a minimum of 9 billion people on the earth. This "scrap" we have laying around is a pitance of what our cultural direction and asset inertis will require in the future. However, since I maintain that will end, we should have an abundance of "everything" as the population level declines.

Will we learn our lesson, or will we try to grow unsustainably once again?

I don't think we really disagree, do we? Sorry if my echoing seemed dismissive of you. I wasn't trying to be.

[MacG]

Will we learn our lesson, or will we try to grow unsustainably once again?

This is a very interesting question which I have thought a lot about. My current take is that we are in for one of those fundamental shifts in human history, like inventing agriculture.

All lifeforms on this earth are subject to the same basic conditions, and I dont think the fundamental ruels will change. I think that they will work in another direction though.

In any system, those who manage to adapt to the conditions in the best way will succeed. In a world with ever increasing amounts of energy, those who exploit that energy will be at advantage over everyone else. Where growth is possible, it will happen. It does not matter if 99% of the population want to conserve, the 1% who exploit the free energy will expand and push the conservationists out.

In a world with ever *shrinking* amounts of energy, the rules will give other results. It might, for example, not make sense to go to war if the net result is that you end up with less resources than before the war. Darwinian principles will take care of the outcome - those with the most successful strategy will ultimately win.

If we indeed *are* over the carrying capacity, the initial stages might favour the violent ones for a period though. The same as before: Whoever adapt best to current conditions will win. If the global population *must* be reduced, the cannibals will be at advantage during the reduction stage, but not neccesarily when steady-state is reached.

The Edo-perio in Japan can give some hints on what a sustainable society can look like. It seem to have been a pretty peaceful period, but many seem to have turned nuts at the end.

[Ludi]

We may have billions of tons of refined metals that we can recycle, but we also have the 6.5 billion people and the infrastructure to support them that requires a huge infusion of energy to maintain. We cannot afford it now with fossil fuels.

I agree, it seems we can't afford it now, because if we could, all of us would be living at the same standard of living (First World) instead of most people living at Third World standards. When we talk about a future of 9 billions of humans, do we see them living at First World standards, or Third World standards? It seems to me, they must be living at Third World standards with a very few (fewer than now) people living at First World standards. Before the advent of fossil fuels, very few people (possibly none) lived at the standard those of us in the First World take for granted today.

[DefiledEngine]

We also have something that previous civilisations did not, which is a sophisticated economic system. The Romans did not particularly bother with budgets. If they wanted to know how much money they had, they looked in the vault. If they need more, they sent an army off to conquer somewhere. History shows if governments try to maintain the system, they screw up. If allowed to work, the much maligned market system may be the thing that finds alternatives. There are clearly limits to the market system, the alternatives may be uneconomic or simply not there. But it is an additional tool in our toolbox.

But isn't it the current economic system that has bought us to where we are? Facing multiple resource depletions? If there had been no political intervention etc. throughout the history of fossil fuels, isn't it likely that we would have used up those resources way faster?
Aren't we sending off armies today to conquer valuable assets?

[bobcousins]

But isn't it the current economic system that has bought us to where we are? Facing multiple resource depletions? If there had been no political intervention etc. throughout the history of fossil fuels, isn't it likely that we would have used up those resources way faster?
Aren't we sending off armies today to conquer valuable assets?

I was expecting someone to make that point. Modern economics doesn't cause resource exploitation, but it does make it quicker. All previous civilisations managed to over exploit resources without modern economics. Resource exploitation is a feature of the organism (overshoot applies to all species).

The free market appears at the moment to create unsustainable growth. But the principle of the free market is that it can also restrict demand, if supply is restricted. In microeconomics, this appears to work. If you look at the prices of commodities, they have maintained low prices (this was the subject of a famous bet by Paul Ehrlich - he lost).

The big question is will this work at the macroeconomic level? Is the free market only effective under the shelter of government policy? For example, it is mainly government programmes that are developing fusion power. No corporation would ever embark on such a huge project. If you look at teh supply/demand curve, a valid solution is found where the supply tends to zero and the price tends to infinity! This is a "market solution" but it doesn't help us if it kills economic activity.

Clearly, the free market has limits. It is not a panacea like economists seem to think. I think the key is to let the free market operate where it has strengths, and use government planning to compensate for its weaknesses.

For example, the free market is an efficient way to manage resource allocation over the short term. A central beauracracy directing individual trucks and shop keepers would be horribly inefficient. On the flip side, the free market is very bad at strategic planning. That is where government programmes to develop and encourage alternatives over the long term come in (by legislation or direct funding).

Of course, it may turn out that modern economics stuffs us up completely, and future economists lit by the flicker of candlelight will scratch out treatises on the importance of a planned economy. But the fact that we have more advanced economic theory makes our civilisation different, which is why it is hard to make direct comparisons with the past.

[MonteQuest]

You still have failed to tell me what energy you would use to create steel in order to create nuclear.

Apparently monte is unfamiliar with the modern steel industry and its love of electric arc mills.

Well, I'm growing more familiar all the time. Seems these electric arc mills produce steel from scrap steel and iron not from iron ore which involves blast furnaces using coke.

So, without coal, electric arc furnaces would be able to remelt the scrap steel and iron produced by the charcoal steel.

While I was wrong about charcoal not being able to produce the heat required, it seems I wasn't wrong about the limitations it had.

We wouldn't ever have produced much steel without the advent and exploitation of fossil fuels. Like Europe almost did, we would have deforested the planet in the process if we had tried.

Hmm...what am I saying? We would have tried and reached "Peak wood."

Some 70% of total steel production is based on the smelting of iron ore in blast furnaces and the subsequent refining of the iron into steel, mainly in Basic Oxygen Furnaces (BOF). A blast furnace typically uses iron ore, coke (made from coal), small quantities of limestone, and, where Pulverised Coal Injection (PCI) is employed, pulverised or granulated thermal coal.

Some 30% of world steel is produced in Electric Arc Furnaces, which melt scrap iron and steel. Much of the electricity used in arc furnaces is generated in coal-fired power stations.

About 630 kg of coal are used to produce 1,000 kg of steel.

Think of how much wood/charcoal it would take.

New processes are being developed for the direct reduction of iron (DRI), eliminating blast furnaces and coke ovens and the need for coke. For examples of such technologies in Australia, see: Coal Use and the Environment - Reducing the Environmental Impacts of Coal Use.

However, DRI plants will still use coal as a fuel and a reductant, and will account for only a small percentage of the world steel output for many years.

For the foreseeable future, coal will remain indispensable to the production of steel.

Link

Scrap metal in the future will be worth it's weight in gold.

[Dukat_Reloaded]

But you can use an electric furnace to smelt. In the future when we have enough nuclear power capacity (if?), smelting ore will be no problem.

[MonteQuest]

But you can use an electric furnace to smelt. In the future when we have enough nuclear power capacity (if?), smelting ore will be no problem.

Yes, but you will still have to use coke from coal or charcoal from wood as a reductant to reduce the iron ore.

That presents a problem.

With scrap metal, no.

[Tanada]

But you can use an electric furnace to smelt. In the future when we have enough nuclear power capacity (if?), smelting ore will be no problem.

Yes, but you will still have to use coke from coal or charcoal from wood as a reductant to reduce the iron ore.

That presents a problem.

With scrap metal, no.

Monte, it is convenient to use coke/charcole as your reductant but not nessecery. You could use for instance, hydrogen gas, or you can capture CO2 and reform it to CO and O2, then use the CO as your reductant. We don't do either much now because they are very energy intensive rather the same way refining Alumina into Aluminum is, they make 'gongealed electricity' in the form of metal from ore.

[Tanada]

Monte, personal observation not criticism. You seem like a nice guy with a deep concern for the future of the human race, but I think you sorely lack the historical depth to understand how we got where we are. This causes you to see the world only as it has been during your lifetime and limits your abillity to see it existing without the cheap oil which you have experienced. We clawed our way up from campfires and stone tools all the way to water and wind mills without petroleum carbon sources. We now have billions of tons of refined metals sitting all over the landscape made with cheap petro carbon resources, but easily availible for recycle in a low growth/no growth post petro carbon world. You bring up the rule of 70 and the limits of exponential growth, but you can't see that human population growth rate has been declining for 40 years and is now projected to stabilize or slowly decline after 2050 AD.

I care to differ. Sure, we clawed our way up, but the total population of the world has remained essentially constant for most of the history of mankind. World population fluctuated between 10 million and 300 million for most of the last 10,000 years, never reaching 1 billion until about 1850. We now have 6.5 billion. Big difference.

I had a brilliant post based on LINK

but the server ate it. I don't have time to rebuild the whole thing, suffice it to say the world carrying capacity without fossil fuels was about 3 billion IMO minimum and the web page linked above will give you a taste of why I think so. Without fossil but with fission I think we can handle a world population of 9 billion, but many people think I am too optimistic.