Tag Archives: sustainability

And then we discovered thermodynamics

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sunEnergy, matter, space and time came into existence in the Big Bang 13.5 billion years ago. 10 billion years later biological organisms started to appear. 70,000 years ago one of those organisms, man started to organise in structures, called cultures and history began. For most of history if you wanted something moved then you had to do it yourself or persuade someone else to do it. The agricultural revolution began 12,000 years ago and shortly afterwards we realised that if you fed fuel to an animal then it would ‘burn’ it and do work for you. And that’s how it remained for thousands of years – we didn’t know how to convert heat into work or work into heat. The average energy consumption per capita was about 20GJ per year. Then, 200 years ago we discovered how to imitate nature by burning fuel and producing power in the steam engine. We had discovered thermodynamics and our average energy consumption started rising towards 80GJ per year today.

As a consequence, ‘we have now all but destroyed this once salubrious planet as a life-support system in fewer than two hundred years, mainly by making thermodynamic whoopee with fossil fuels’ as Kurt Vonnegut wrote. And that’s because nature starts from solar energy and recycles everything and we haven’t learnt how to do either very effectively. But energy or power engineering has been around for less than a blink of eye relatively speaking and we are just learning how to perform a trick nature has been using for billions of years: convert solar radiation into other energy forms. The sun delivers about 340 Watts per square metre to the Earth so we have plenty energy available.

If you would like to know more about energy engineering or thermodynamics and its potential then join the 5000 people who have signed up for the MOOC that I am teaching for five weeks from next Monday.  Listen to me interview Ken Durose, Director of the Stephenson Institute for Renewable Energy on the prospects for renewable energy.

Sources:

http://ourfiniteworld.com/2012/03/12/world-energy-consumption-since-1820-in-charts/

Yuval Noah Harari, Sapiens: A brief history of mankind. London: Vintage (Penguin, Random House), 2014.

Kurt Vonnegut, A Man without a Country, New York: Seven Stories Press, 2005.

Our place in the web of life

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140-4032_IMGThe seven billion human beings who live on this planet weigh in about 300 million tonnes in total and if you add in our domesticated animals then the scales would hit about 700 million tonnes. Whereas if you weighed all of the animals left in the wild then their total weight would be less than 100 million tonnes, according to Yuval Noah Harari in his book ‘Sapiens: a brief history of mankind’. This explains why many of our landscapes appear empty and barren – they are, at least at the level of large mammals. That’s why you are unlikely to be chased by a tiger or any other predator, see last week’s post entitled ‘Running away from tigers’.

These landscapes are not really barren. We just can’t see what is there. Bacteria are too small for us to see but they have dominated the landscape for most of evolutionary time. They ‘invented’ all of life’s essential biotechnologies including fermentation, photosynthesis, nitrogen fixation, respiration and devices for rapid motion plus probably a few we have haven’t discovered yet. Bacteria exchange up to 15% of their genetic material on a daily basis across all strains so that they could be considered to form a single microscopic web of life.

This web of bacterial life is all around us as well as inside us. If you like to learn more than you probably ever want to know about the bacteria inside us then read Giulia Enders’book ‘Gut: The inside story of our bodies most underrated organ’. We are not alone in being immersed in this web of bacterial life; so is every other living thing which implies we are all intimately connected in a vast ecological network. This microbial web of life in which we are embedded is self-organising – there are no leaders, presidents, generals or CEOs – instead bacteria empower one another. It appears to be one of the secrets of their success.

In an interconnected world, power and control over others in a hierarchy is less appropriate than empowering one another in the network. Many people would find this approach difficult because they identify themselves with their position of power and, hence would tend to resist any attempt to empower the network. To them it begins to sound like anarchy, particularly in the narrow context of human society, but others might suggest it offers a better prospect for addressing the challenges posed by global climate change than world leaders have so far proposed. Well-informed individuals intimately connected in a network are likely to take decisions that support the network, and hence themselves. But, now we are straying into game theory…

Sources:

Yuval Noah Harari, Sapiens: A brief history of mankind. London: Vintage (Penguin, Random House), 2014.

Capri F. & Luisi, P.L., The systems view of life: a unifying vision. Cambridge: Cambridge University Press, 2014.

Enders, G, Gut: the inside story of our bodies most underrated organ. Vancouver: Greystone Books, 2013.

Running away from tigers

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rsph graphicToday, the probability that you will have to run away from a tiger is very small, no matter where you live.  Tigers have lost 93% of their historical range that used to stretch from Turkey across Asia to Eastern China and southwards to Indonesia.  Tigers have no problem with the first law of thermodynamics – they instinctively know that if they take in more energy than they expend then the excess energy will be stored as fat and when they become overweight they won’t be able to catch you or whatever else they decided to chase for their next meal.

As a species we seem to have lost that understanding of energy balances.   Obesity is increasing in many parts of the world.  The situation is so serious in the UK, where more than two-thirds of the adult population are overweight or obese, that the Royal Society for Public Health has proposed that food should be labelled with the amount of exercise required to burn-off the calories it contains and they have suggested using the infographic in the thumbnail.  Of course, the Royal Society’s position paper does not mention explicitly thermodynamics (or tigers!) though it does effectively cite the first law by stating ‘the cause of obesity is excess energy consumption relative to energy expenditure‘.  By coincidence, this week I interviewed Professor Graham Kemp, in the Institute of Ageing and Chronic Disease in Liverpool, about energy flows through our bodies for a MOOC on Energy: Thermodynamics in Everyday Life.

If you wathermolectures posternt to listen to that interview or learn more about the thermodynamics underpinning the energy balances controlling our weight, climate change and your electricity charges, then you need to join the more than 4,500 people who have already enrolled on the MOOC that will run for five weeks from February 8th, 2016.  I will also be giving an accompanying series of lectures in London.

I was astonished to discover that there are fewer tigers in the world than people signed up for our MOOC.  Less than 3,200 tigers exist in the wild mainly because our growing population and prolifigate use of the world’s resources has destroyed their habitat and those of the other species with which we share this planet.

 

 

 

Small is beautiful and economic

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tractorFarm tractors have been growing bigger and bigger, though perhaps not everywhere – the photograph was taken in Donegal, Ireland earlier this year.  The size of tractors is driven by the economics of needing a driver in the cab. The labour costs are high in many places, so that the productivity per tractor driver has to be high too.  Hence, the tractors have to move fast and process a large amount of the field on each pass.  This leads to enormous tractors that weigh a lot and exert a large pressure on the soil, which in turn results in between 1 and 3% of the farm land becoming unproductive because crops won’t grow in the severely compressed soil. But what happens if we eliminate the need for the driver by using autonomous vehicles? Then, we can have smaller vehicles working 24/7 that do less damage and are cheaper, which means that a single machine breakdown doesn’t bring work to halt. We can also contemplate tailoring the farming of each field to the local environmental and soil conditions instead a mono-crop one-size fits all approach. These are not my ideas but were espoused by Peter Cooke of the Queensland University of Technology at a recent meeting at the Royal Society on ‘Robotics and Autonomous Systems’.

It is a similar argument for modular nuclear power stations. Most of the world is intent on building enormous reactors capable of generating several GigaWatts of power (that’s typically 3 with nine zeros after it) at a cost of around £8 billion (that’s 8 with nine zeros) so about 50 pence per Watt. Such a massive amount of power requires a massive infrastructure to deliver the power to where it is need and a shutdown for maintenance or a breakdown potentially cuts power to about a million people. The alternative is small modular reactors built, and later dismantled, in a factory that leave an uncontaminated site at a lower capital cost and which provide a more flexible power feed into the national grid. Some commentators (see for example Editor’s comment in Professsional Engineer, November 2015)believe that a factory could be established and rolling modular reactors off its production line on the same timescale as building a GigaWatt station.

Regular readers will recognise a familiar theme found in Small is beautiful and affordable in nuclear powerstations on January 14th, 2015, Enabling or disruptive technology for nuclear engineering on January 28th, 2015 and Small is beautiful on October 10th, 2012; as well as the agricultural theme in Knowledge-economy on January 1st, 2014.