Monday, August 13, 2012

Population Surge: "10 Billion" - Stephen Emmott speaking at The Royal Court Theatre in London.

There has been a highly successful run at the Royal Court Theatre, in London, not of a play in the usual form, but of a lecture by Professor Stephen Emmott, who leads Microsoft's Computational Science Laboratory in Cambridge and is Professor of Computational Science at Oxford University. The title, "10 Billion" refers to the human population which it is thought may rise to this number by the end of the present century, with back-breaking pressure on the available resources of the Earth: principally those of food, freshwater, and energy. I attended its final performance last Saturday.

Since the inevitable outcome of consumption is excretion, by that time, we will be drowning in our own waste, particularly carbon, such that many lands including Bangladesh will be inundated. The global temperature rise, too, is thought not to be a mere 2 degrees C by the end of the century but 6 degrees, making life on earth, as Emmott describes it "a living hell."

Emmott describes himself as a "rational pessimist" and while his delivery is tinged with ironic humour, it is mostly deadpan, rendering the sheer facts and figures both compelling and convincing. I was at one time skeptical about global warming and its consequences, but now there seems to me little room for doubt that humanity is in a severe predicament, both from the aspect of resource depletion and treating the planet like a giant landfill tip.

Emmott points out that we are using all of the arable land available to us, as a population of 7 billion, and that to feed 10 billion will require clearing forested land, including rainforests which have been described as the "lungs of the earth".

Of all resources, that most critically threatened is water, and it is staggering the quantities of "hidden water" that are used to provide some very commonplace items. For example, it takes 3,000 litres of water to produce a beefburger, and in Britain some 10 billion burgers are consumed per year, therefore necessitating the consumption of 30 trillion litres, or 30 cubic kilometers (km^3) of water.

It takes 27,000 litres of water to produce one bar of chocolate.

100 litres of water are used to make one cup of coffee.

It takes 4 litres of water to make one one litre plastic bottle of water... that's before the water is put into it.

At a population of 7 billion, our energy consumption amounts to around 16 TW, and this will need to rise to 20 TW to provide for the eponymous "10 billion". Since we are highly dependent on fossil fuels, oil, gas and coal, which provide around 87% of the total energy used by humans on earth, our greenhouse gas emissions will almost certainly have to rise, given the limitations of renewable energy sources.

30% of greenhouse gas emissions originate from food production, which is more than from transportation or manufacturing.

To meet that 20 TW of energy, while avoiding burning carbon at an accelerated rate. would require building 960 new hydroelectric dams, each the size of the Three Gorges Dam which spans the Yangtze River in China, PLUS 15,000 NEW nuclear power plants. In terms of uranium fuel resources alone this does not seem very realistic, let alone making sufficient concrete (a hugely CO2 emitting process) for both dams and NPPs.

It is expected that demand for food will double by 2050. This not only reflects the rise in population per se, but that more affluent people eat more food, and the consumer society is expected to expand within that number.

Emmott gave two choices: to "technologise" our way out of trouble, but concluded this was unlikely to be possible and the other option was to "change our behaviour", by consuming less food, less water, and less "stuff". Surplus cash for "stuff" arose when food became cheap in consequence of the Green Revolution. Food prices are rising significantly, and the current US drought could have a drastic effect on world grain availability, with consequences across the world. A drought in Russia recently meant that some 40% of an expected 100 million tonnes of wheat was not produced. Russia held onto supplies to feed its own people which led to food shortages and riots in the far east, India and Pakistan. Emmott speculates, "imagine if that same proportion of the 400 million tonne US wheat output was lost"... indeed, the outcome would be catastrophic.

He is less than sanguine that humans will change their behaviour, believing that developing nations will still aspire to a western lifestyle, whereas the reality is that in the west we need to consume less while more than one billion people in the non-legacy nations, who are malnourished, need to consume more. And the outcome of this? As he puts it, "We're fucked", and I suspect he may well be right.

Apparently, species on Earth are becoming extinct at a rate one thousand times faster than the normal evolutionary rate as we consume the planet's resources.

In 1960, there were 100 billion air-miles flown. In 1980 this had risen to 1,000 billion air-miles and now it is 6,000 billion.

Emmott draws the analogy that if it were known that an asteroid was on its way and would hit the Earth in the year 2094, say, Astronomy and Physics being "simple subjects" would allow a precise prediction of the date and moment of impact and where exactly on Earth it would strike. He says that in such a case, the entire world would mobilise its resources, (1) to mitigate the damage and loss of life from the impact itself, and (2) to inaugurate the most effective procedures for how to cope in its aftermath. Although the likely number of casualties may well be of the same order, the threat to humans is not an external source, like an asteroid, but it is ourselves and our behaviour and yet we do nothing.

What however is the likelihood that the world human population will rise to 10 billion. According to UN's 2010 revision of its population projections, it will peak at 10.1bn in 2100. Some experts dispute the UN's forecast and have argued that birthrates will fall below replacement rate in the 2020s. According to these forecasters, population growth will be only sustained till the 2040s by rising longevity but will peak below 9bn by 2050.

That noted, a worst case scenario predicts that the world population will peak at 7.1 billion in 2024, and then fall to 2.5 billion (close to the estimated carrying capacity of the planet) by 2100. The latter assumes nothing and is a simple mathematical curve-fit of a logistic (population growth) function to actual population data. Is this a mathematical artefact or a simple reflection of a population with limited resources, like the behaviour of bacteria growing on nutrient agar in a Petri dish? Only time will tell, but the "10 Billion" problem may never arise, let alone 16 billion by the end of the century. We are an overshoot species, and may expect a rapid cull, as in the S-shaped curve that prevails for bacteria. The initial growth is slow, but then given sufficient resources (food - oil, and gas in the human situation), the population rapidly escalates until it can no longer be sustained by its food. Then the bacteria begin to starve and consume each other.

14 comments:

MSM said...

Nice writeup. Thanks for fighting the good fight -- we are in a heck of a predicament.

I note that if we consider each of 10 B people to expend food power at 120 W each, then that alone adds up to 1.2 TW. Taking your 30% energy share of 20 TW, that is 6 TW, for food production gives about 5 times as much energy inputs compared to the food energy metabolized.

For 10 B people using 20 TW energy, of which perhaps half of that is oil, then, with oil having, say 36 MJ per liter, then the per capita consumption would be 4.8 liters per person per day. (Google told me this number when using the search string, "20 terawatt /((10 billion)*36 megajoule per liter) in liters per day".)

I think working the data and numbers, and ever refining and retelling the story they hold as you do, can only help us and our degrading biosphere.

Chris Rhodes said...

Dear MSM,

it's interesting to look at raw energy figures as you have. That would amount to each person using energy at a rate of 2 kW. Assuming that one third of total energy is used in the form of crude oil, that would equal 100 million barrels (160 l = 1 b) per day for 10 billion people...

Now, current total world production of ACTUAL crude oil is around 74 mbd (expected to decline by 3.4%/year) and the U.S. uses around 19 mbd (population 311 m)... clearly that use of oil/energy would not be equal across a population of 10 billion, and the total could not be sustained in total oil demand.

So, we can expect a great shift to a less oil (transport) dependent civilization. Localisation seems to be rearing its head once more.

Regards,

Chris

Anonymous said...

Hey Chris...long time.

In general I agree with the arguement that humans will see to their own demise. My only concern is when a computational scientist is given so much latitude simply because he has access to the ability to generate models and wonderful presentations based on many others research. I have worked for years with many computational scientist, and they generally will take consitutive models to their extreme to produce interest in their otherwise mundane work.

If anybody knows anything about "Global Warming" it is the fact that it will produce massive flooding in many regions of the world and draughts in others.The high altitude water vapor will shift things on a swift cooling trend that will have far greater devistation than the warming.

Even so, I don't think we need an overpaid computational scientist to tell us how things will be when we have a perfect historical example called "Easter Island".

The bacteria begin to starve and consume each other...

Cheers Mate!

Ken S/V Trim

Chris Rhodes said...

Hi Ken,

it has indeed been a while and I hope all is well with you - are you still on the boat?

Interesting what you say about the high altitude water vapour. So, is the idea that there is initial heating and more evaporation of water, which then provides a swift "refrigerating effect"? I have heard Wally Broecker's theory that the Conveyor will shut down as Arctic ice melts and dilutes the saline water where it is supposed to sink.

This, it is thought, will switch-off the Gulf Stream and so the UK, being on the same latitude as Hamilton, Canada will freeze along with the rest of northern Europe.

Your mechanism seems something else - is it of the kind that I suggest?

In reference to the "overpaid computer scientist", in his lecture he said that "it takes as much energy to do one Google search as to boil a kettle of water", a "fact" that I put in the original article on here. I then got an irate message from a PR person at Google that this has been disproved and would I remove the allegation - which I did. I gather they are also on to the Royal Court Theatre and Professor Emmott to stop him making this claim!


Cheers,

Chris

Unknown said...

Hey Chris,

We are taking a break from the sailing to refill the kitty. I'm working in Australia as a VOC remediation expert of all things!

Having sailed half way around the planet and expecienced global warming up close and personal without the aid of a NASA model, its effects in the tropical regions are clearly defined by higher temperature equitorial water, substatially increased evening convection, rain and most importantly, increased cloud cover.

Enjoy:
http://meteora.ucsd.edu/~jnorris/presentations/Caltechweb.pdf

Unknown said...

Actually, this is a good refernce to read with regard to computational modeling limits of finite difference.
http://meteora.ucsd.edu/~jnorris/presentations/climate_model_clouds.pdf

Even so, I believe Easter Island to be a good case study for the subject of over population and limited resources. I have no doubt that "Long Pig" will be the difference between life and death if the situation reaches the breaking point.

Chris Rhodes said...

I have wondered whether the next ice age is due (not in "The Day After Tomorrow" kind of rapidity) within our lifetimes? We have been in an interglacial for abut 11,000 years and so looking back at the fossil record, it may be overdue but held-back by Global Warming. So, if increased cloud cover increases the albedo, then a cooling trend could set in?

Interesting what you say about warming tropical waters. I gather also that the Atlantic Conveyor has slowed in recent years and so maybe we are into the cooling trend?

In regard to those limited resources - yes, maybe we will behave more closely to those bacteria than I'd like to think, and literally "eat one an another"!

You must have an almost unique perspective - i.e. to see the effects of GW at close hand - and indeed, you don't need a computer simulation!

Cheers,

Chris

Anonymous said...

I don't think we are anywhere near done warming yet, but I do tend to believe with many others that the cooling trend comes hard and fast. The one thing I have learned first hand is the enormous power of the equatorial currents. When we crossed the equator several years ago during El nino, there was current of 5+ knots which was more than 50 miles wide and who knows how deep. The water temperature of that current was nearly 8 degrees colder than the surrounding water. It's my guess that the thermal energy of such a current represents more energy than humans have consumed for years or decades...probably more.

Alex P. said...

Interesting post, even if I don' t completely agree with your conclusions.

I think there are still in the planet enough resources (not necessarily fossils) to power a 10 billion people planet, even at a "western" energy consumption. There are at least two strategies/technologies we should implement quickly : 1) nuclear energy not based like today on inefficient solid fuel uranium but molten salt thorium breeders tech - besides the intrinsic advantages in terms of safety and long life wastes reduction, it takes no more than 5000-10,000 tonn/year of thorium (an almost negligible figure, pratically the actual Th wastes from current rare earthes mining)) to power such a 10-bil people planet; and some innovative renewable sources like high altitude wind, hot rocks deep geothermal, solar thermal in deserts, etc.. 2) a good liquid fuel carrier like methanol from biomass, requiring no more than 1 tonn of dry biomass per 1500 liter of MeOH, if electricity (from the sources cited in the point 1)) is used to produce in situ the hydrogen need for the water/gas shift reaction, halving at least the need of biomass input (one mole of H2 is produced externally using renewable and (nuclear) thorium electricity and an other one is "free" from biomass gasification per mole of methanol output); together obviously with a deep electrification of both private and collective transportation (train, trams and electric and plugins vehicles) and heating/conditioning (via high efficiency heat pumps)

Chris Rhodes said...

Hi Alex,

I agree that there is probably enough energy content per se in thorium to run 10 billion, but it’s going to take quite some while to install it all, and huge quantities of energy and other resources to do it. I think the major issue is that we don’t have too much time to do it, especially as our liquid fuels supply declines. And we use liquid fuels to mine and produce most materials including energy sources.
I tend to favour thorium for the reasons you say, and yes, the LFRs , not the impractically huge accelerator driven systems.
I agree too, that in principle we could make H2 by electrolysis and feed that into systems to produce methanol from syngas. But, the installation of the technology on the grand scale is going to take a gargantuan amount of energy, resources and time. And time is what we don’t have.
I also agree that heavy investment in electric rrail systems for moving people and goods around is likely to be a critical strategy as the cheap fuel supplies decline.
In the UK, the east side of the county has used electric trains for many years but now the west side is set to be electrified. Although so much has not been spelled-out, I am pretty sure that the government knows full well what the problem is, and is quietly trying to install alternative means for transportation in the absence of plentiful cheap oil.
And as you say, energy efficiency is key.

Regards,

Chris

Alex P. said...

Well, Chris, if for "resources" you mean time and/or money I might agree with you, on the other hand I think there are enough physical resources to power a 10-bill planet even at western energy consumption if you consider that we' d need in that case only less than 10,000 tonn/year of natural thorium (to produce 100 thousands TWh/year of electricity) and no more than 4-5 billions tonns of dry biomass to produce 60-70 milion bpd of oil equivalent as methanol, i.e. 2 liter of methanol = 1 liter of gasoline (I don't think we need such a high figure in a deep electrified transportation scenario)


Interesting enough a thorium LFTR being an high temp system (> 700 °C in the hot leg) can be also an interesting way to produce by cogeneration power + low temp heat for example for district heating, industrial processes and seawater desalination, particurally in developed countries

Obviously, even in a future scenario of deep electrification of both trasnportation and heating/conditioning we'll always need a lot of liquid fuels,at least to power trucks, ships, airplanes, etc... in this sense the role of methanol (and/or DME for diesel engines and turbines) can be of some importance , particurally if you consider the gain in efficiency (per Joule) of optimized Otto/gasoline methanol engines (or Diesel engines for DME) - by the way, have you ever looked at the potential improvements in efficiency if it ued in optimized internal combustion MeOH engines (besides the use in more controversial fuel cells) ?

Chris Rhodes said...

Hi Alex,

I agree that time/money are the greatest limiting factors. I know that thorium has abundance of around 3x that of Uranium, taken as an average composition of the earth's crust.

I went to a talk the other night by Richard Lllewelyn - of the UK TV series "Red Dwarf" - who is an electric car enthusiast. Now from my point of view there are resource issues and he said himself, that if the number of them isn't limited by lithium, it will be by how much rubber etc. that would be needed to make one billion electric cars.

And of course time is the critical factor, hence my view (and yours too, I think) that we need deeply imbedded electric transport.

But he said that there was a plant working in South Korea that extracts lithium from seawater. As far as I can tell, there isn't one working as yet, but I gather the project is underway. What the EROEI etc. is I don't know, because I can't find details of how they do (or propose to do) it.

I am imagining it involves some kind of cation-exchange technology, otherwise the energy costs would be prohibitive. I know anoither guy who is working on membranes for selectively capturing uranium from seawater. Anything practical looks to be a long way off, but it is interesting to see this rear its head again.

I have a "Look and Learn" book here from 1966 - bought for me as a young child! - and there is a section in that talking about all the elements in the sea, and that "one day" - the proverbial! - mankind would be extracting them from this effectively limitless source. Mind you, they also said we would have nuclear fusion power "in ten years time"!

On the matter of methanol, I have just written an article to be published as a commentary in Science Progress, on carbon capture and storage. I have a section in that about usefully catching carbon, to make it into useful materials, rather than locking it away underground, e.g. in the form of methanol.

So, you might be interested in the following snip from it - particularly the final paragraph - in the context of your question:

"Production of methanol.
Methanol is readily produced from CO2 and H2 (equation 3). In the Green-Methanol Synthesis18, waste CO2 from power stations or from industry is used, rather than releasing the gas into the atmosphere, while the hydrogen gas is generated by the electrolysis of water using electricity produced entirely from renewable sources, e.g. wind, solar, biomass. It would appear, therefore, that it is the latter that is a limiting factor in how much carbon might be captured in the form of methanol, along with the inauguration of new engineering on a considerable scale. A methanol economy based on the green-methanol synthesis has been proposed as an alternative to the hydrogen economy.

Since it is a liquid fuel, methanol can be used in the current fuel infrastructure, while an entirely new system of distribution, and actual use in vehicles, would need to be built from scratch to run the hydrogen economy. Although methanol only contains about half the energy of petrol or diesel, volume for volume, it has an octane rating of 113. Hence, mixing 10% methanol with 90% gasoline (with an octane rating of 90) will yield a blended octane value (BOV) of 130. It has been demonstrated that blends of up to 20% methanol result in an increased fuel economy, while the actual gains precisely depend on the type of vehicle. It was found that an engine running on neat methanol had a peak efficiency of nearly 43%, and maintained >40% efficiency over a much wider range of speeds and loads than does a conventional diesel engine."

Regards,

Chris

Chris Rhodes said...

Hi Alex,

I agree that time/money are the greatest limiting factors. I know that thorium has abundance of around 3x that of Uranium, taken as an average composition of the earth's crust.

I went to a talk the other night by Richard Lllewelyn - of the UK TV series "Red Dwarf" - who is an electric car enthusiast. Now from my point of view there are resource issues and he said himself, that if the number of them isn't limited by lithium, it will be by how much rubber etc. that would be needed to make one billion electric cars.

And of course time is the critical factor, hence my view (and yours too, I think) that we need deeply imbedded electric transport.

But he said that there was a plant working in South Korea that extracts lithium from seawater. As far as I can tell, there isn't one working as yet, but I gather the project is underway. What the EROEI etc. is I don't know, because I can't find details of how they do (or propose to do) it.

I am imagining it involves some kind of cation-exchange technology, otherwise the energy costs would be prohibitive. I know anoither guy who is working on membranes for selectively capturing uranium from seawater. Anything practical looks to be a long way off, but it is interesting to see this rear its head again.

I have a "Look and Learn" book here from 1966 - bought for me as a young child! - and there is a section in that talking about all the elements in the sea, and that "one day" - the proverbial! - mankind would be extracting them from this effectively limitless source. Mind you, they also said we would have nuclear fusion power "in ten years time"!

On the matter of methanol, I have just written an article to be published as a commentary in Science Progress, on carbon capture and storage. I have a section in that about usefully catching carbon, to make it into useful materials, rather than locking it away underground, e.g. in the form of methanol.

So, you might be interested in the following snip from it - particularly the final paragraph - in the context of your question:

"Production of methanol.
Methanol is readily produced from CO2 and H2 (equation 3). In the Green-Methanol Synthesis18, waste CO2 from power stations or from industry is used, rather than releasing the gas into the atmosphere, while the hydrogen gas is generated by the electrolysis of water using electricity produced entirely from renewable sources, e.g. wind, solar, biomass. It would appear, therefore, that it is the latter that is a limiting factor in how much carbon might be captured in the form of methanol, along with the inauguration of new engineering on a considerable scale. A methanol economy based on the green-methanol synthesis has been proposed as an alternative to the hydrogen economy.

Since it is a liquid fuel, methanol can be used in the current fuel infrastructure, while an entirely new system of distribution, and actual use in vehicles, would need to be built from scratch to run the hydrogen economy. Although methanol only contains about half the energy of petrol or diesel, volume for volume, it has an octane rating of 113. Hence, mixing 10% methanol with 90% gasoline (with an octane rating of 90) will yield a blended octane value (BOV) of 130. It has been demonstrated that blends of up to 20% methanol result in an increased fuel economy, while the actual gains precisely depend on the type of vehicle. It was found that an engine running on neat methanol had a peak efficiency of nearly 43%, and maintained >40% efficiency over a much wider range of speeds and loads than does a conventional diesel engine."

Regards,

Chris

Alex P. said...

Thanks, Chris, I'm quite interested, have you got a link to that article ?

Anyway, there is an other important fact I want to do note about *bio*methanol that means, in this context, methanol from biomass gasification (yielding the syngas mixture of CO + H2): because the reaction CO + 2 H2 = CH3OH is used (rather than CO2 + 3 H2 = CH3OH + H2O), besides the adv not to have steam in the second member, much less hydrogen thus energy/electricity is needed, in particular only one mole of hydrogen (the other one is produced by biomass gasification yielding a ratio of CO/H2 ~ 1) per mole of MeOH vs 3 moles H2 per mole of MeOH in the latter more inefficient case

I think this is an important aspect because to produce for example 60 milions of bpd of oil equivalent as MeOH (even with no efficiency gain, thus it takes 2 liters of MeOH to replace 1 liter of gasoline) with an oil refiniment efficiency of, say, 90%, it takes about 4-4,5 billion tonns of dry biomass per year and 12,000 TWh/year of electricity - *IF* high temp electrolisys (even at average temp of ~ 150 °C) is used needing only 35-40 kWh of electricity to produce one kg of hydrogen and to compress it
http://ieahia.org/pdfs/Task25/High_Temperature_Electrolysis_(HTE).pdf; both figures are very high but I think still managable, particurally if molten salt thorium breeders and other renewables are successfull developed