Category Archives: sustainability

Extraordinary technical intelligence

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In his book ‘A History of the World’, Andrew Marr identifies a recurring process in the development of societies, from an agricultural revolution that releases enough people from food production in the countryside to enable basic manufacturing in town and cities, through an industrial revolutions leading to more sophisticated manufacturing and a large, rapid rise in the standards of living.  This process happened first in Britain during the 18th and 19th century, in the US during the 19th and 20th century and then more quickly in Japan, Korea and Taiwan in the second half of the 20th century.  It is happening now and even faster in China with the same ‘grim working conditions in the factories, the raucous enjoyment of plenty by the winners in the cities and a certain recklessness about pollution’ to quote Andrew Marr [Marr, A., A History of the World, MacMillan, 2012].  It is starting in India and Africa might be next, though in the Financial Times on Friday 22nd March, 2013 Chandran Nair argues that we should reverse the flow from the countryside to the cities if we want to achieve a sustainable society.  This might just be possible in Africa, probably not in India and China seems set to follow the well-beaten path to urban industrialisation.

What comes next in the process?  Perhaps a loss of interest in manufacturing industry, followed by over-spending by individuals and governments, economic recession or collapse and stagnation of growth.  Andrew Marr suggests that the wealth based on manufacturing derives from ‘mankind’s extraordinary technical intelligence’ and that there is ‘a long lag in advancing our political and social intelligence’.  The stale-mate at the heart of US politics and the failure of successive UK governments to avert a multi-dip economic recession would suggest the need to advance our political intelligence.  In the meantime we might lose our technical intelligence if don’t train more graduates in technology [see my post on Financial crisis, 27th March, 2013].

Something for nothing?

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Let’s try a thought experiment, following on from my previous post (Beyond Zero on 20th February, 2013).  Imagine two equal amounts of matter, A and B at -350 Kelvin and 350 Kelvin respectively.  We would expect heat to flow from the hot one, that’s B to A, the cold one.  This would cause the internal energy of B to decrease with a corresponding rise in the internal energy of A so that B gets colder while A gets hotter, i.e. they both move closer to absolute zero with corresponding decreases in entropy.  The Second Law of Thermodynamics does not allow this to happen and in fact the reverse would occur, i.e. heat would flow from the cold one A to B, lowering the temperature of A and raising the temperature of B so that they both move away from absolute zero with corresponding increases in entropy.coldgraph2

IF we could actually make this happen then we would able to design engines with efficiencies higher that 100%.  One corollary of the Second Law of Thermodynamics is that heat cannot be converted into work without some of the heat being wasted or lost as entropy.  In a power station, heat is taken from a hot source (e.g. a nuclear reactor, solar concentrator or gas furnace) and some of it converted into shaft work, which turns a generator to produce electricity, while the remainder is dumped into a cold sink usually the environment via cooling towers.  However, if our cold sink was at a negative temperature on the Kelvin scale then we could take heat from the cold sink and the hot source at the same time!  Why aren’t we doing this?  Well, we don’t have any naturally occurring cold sinks at below zero Kelvin and to create one uses more energy than we would gain in our super-efficient power station – that’s the Second Law kicking in again.  So you can’t have something for nothing.

Food waste

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korea cafeteriaIt has been reported recently that there are more people suffering from obesity in the world than from malnutrition (http://www.ifrc.org/en/publications-and-reports/world-disasters-report/wdr2011/).  This might suggest that global society has a major distribution problem to solve and that current approaches are failing.  This is a tentative conclusion supported by another recent report which estimates that half of global food production is wasted (http://www.imeche.org/knowledge/themes/environment/global-food).  Some agricultural production never reaches the distribution system and rots in the fields, while some is disposed of untouched by end-purchasers.  Presumably end-purchasers throwing away uneaten food are not starving and probably a high proportion of them are obese.

The second law of thermodynamics demands that there must be waste in all processes, so we can never reduce the wasted food production to zero but 50% wastage seems high and perhaps implies we some way to go before population growth is limited by food production (see post on ‘Two Earths’ in August 13th, 2012 or ‘Population crunch’ on September 15th, 2012).  Of course, if the majority of current food production is unsustainable then we are in trouble already.

Unavoidable junk

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167-6734_IMGThe laws of thermodynamics are physical laws whose relevance extend beyond the study of engines and heat plants.  We can restate the first law of thermodynamics (conservation of energy) as ‘the quantity of matter is constant and finite’.  Matter changes both in nature and as it moves through the economic system; and as it does so, its intrinsic properties change rendering it less useful and usable, thus requiring more and more resources to make it useful again.  This last sentence is a form of the second law of thermodynamics.  Very useful (low entropy) goods, such as iron ore and fossil fuels, eventually produce less useful (high entropy) matter, such as piles of junk cars in scrap-metal yards and greenhouse gases, as they move through the economic system.  In our current western life-style, we are all contributing to the generation of vast piles of junk; we are hooked on it; we are all ‘junkies’.

In the paragraph above, I have plagiarised the 2009 report entitled ‘The New Sustainable Frontier’ mentioned in the previous posting on this blog [http://www.gsa.gov/graphics/ogp/2009_New_Sustainable_Frontier_Complete_Guide.pdf ].  However, similar ideas were expressed by Handscombe and Patterson in their 2004 book entitled the ‘Entropy Vector’ [http://www.worldscientific.com/worldscibooks/10.1142/5365 ].  They paraphrased the first and second laws of thermodynamics as ‘you can’t have something nothing’ and ‘you can’t have it just anyway you like it’.