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Sustainable energy

 

 

 

It is hoped a carbon tax will make a variety of alternative energy sources and transport technologies economically viable.  Chief amongst these is the fission of uranium and its daughters (nuclear power).  It is already the principal source of electricity in over half a dozen countries including France, Belgium, Sweden and Finland and a very significant contributor in Japan, Korea, Canada and several States of the USA. There are presently over 400 commercial plants running and another 60 under construction worldwide.   After coal, nuclear power is the largest source of electricity in the world.  It is the only realistic contender, at current prices, as a replacement for fossil fuel. 

But fission power is not renewable energy.  Easily available uranium reserves are limited.  Although fissile material is very wide spread there are limited sources in sufficient concentrations to make extraction economic.   The lifespan of reserves can be extended considerably using fast-breeder technology but this is more dangerous and lends itself more easily to weapons making.

The principal sources of sustainable energy in Australia today are biomass /biogas and hydroelectric power.  For example, wood burning still provides over 25 times the energy supplied by wind, the next largest source.  The contribution wind and solar make is still insignificant (less than 0.2%).

But solar power shows great promise, particularly in warm temperate areas with low cloud cover such as can be found in Australia, the United States and Southern Europe.  Where these are distant from areas of high population density, solar power stations could be used to generate hydrogen, manufacture aluminium, titanium or other energy intensive materials.

Solar power is close to being economic in many situations, particularly for domestic electricity supply where it has the advantage of no grid losses and a relatively easy match of collector area (supply) to demand.  But in high latitudes and where cloud cover is typically high, sunlight hours can be very short.  In some northern cities a collector that covered the entire map would not receive as much energy as they use (as one wit observed, it would be very dark under the collector) and in many tropical areas almost continuous cloud reduces the practicality of solar even for domestic use. 

The ideal solar power station would be located where there is no cloud cover and there is 24 hours of daylight.  So solar power may be most effectively implemented, on the scale required, if collected in space and the energy sent to earth by microwave.  If this could be implemented it might satisfy our energy needs indefinitely.  But dangers include its potential use as a weapon (death ray), accidents and environmental damage that might result.  It would obviously be a very technology intensive solution.

Some states (California) and countries (Denmark) have embraced wind, geothermal (Iceland) or wave power as a solution.  But the available resources are at least two orders of magnitude too small to provide for world energy needs, particularly if we need to substitute electricity for oil as transport fuel.  They are interesting sideshow used to establish ‘green credentials’ but can go nowhere near satisfying the energy demands of the developing world. 

Of course corporations manufacturing and promoting the proliferation of wind turbines (eg in California and Denmark) like to talk about how many houses a wind farm will supply; failing to mention that domestic energy demand is little more than twelve percent of the total demand and at the present time wind can go nowhere near meeting even that demand without a substantial input from gas and or other forms of combustion.  If land transport is to be predominantly run on electricity in future, present electricity generation capacity will need to expand by three or four times.  This is completely beyond the availability, let alone capability, of wind energy.

Alternative energy (particularly wind power) is often accompanied by understated environmental and other costs that would become all too apparent if scaled up to anything like present oil or nuclear energy sources.  Although some may be economic as energy prices rise, particularly in isolated areas, they can contribute very little to our overall energy needs.  They can effectively be ignored as significant elements in a broader world energy strategy to sustain human civilisation and power its future economic growth and survival.

Most informed commentators since the 1970s have taken it as obvious that the use of fossil fuels is but an interim solution to humanity’s future energy needs.  They have pointed out that there is more than enough energy available for all our needs from the sun and from deuterium in the oceans. 

Deuterium (heavy hydrogen) provides the energy released by the hydrogen bomb (and the sun).  This was first demonstrated at Bikini atoll, rather spectacularly, in 1952.

 

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Deuterium is obtained from heavy water extracted from the sea.  The economic reserves are effectively limitless. 

But to harness this energy safely is very difficult and we still have not mastered it.  It will require a nuclear power stations that are much more sophisticated than those we possess today.  In order to accomplish this we will need a great need number of trained engineers and physicists.  We were on the way to achieving this with the advent of nuclear power using fission technology, but a series of early accidents, combined with its use by irresponsible politicians and generals to kill people and damage the environment, gave nuclear opponents the opportunity to block this direction of progress in several advanced economies. 

 

 

Bio-fuels

 

 

Of course solar is the source from which bio-fuels gain their energy.  But the contribution of bio-fuels is presently strictly limited by resource availability (suitable land and water).  Under present technologies they compete for resources with food production and are even leading to the further destruction of natural forest. As they are never likely to contribute more than a few percent of our transport energy requirements some critics are already questioning government market interference aimed at their expansion.  But biotechnology may offer solutions that could make bio-fuel a possible serious contender as replacement transport fuel.  Genetically modified algae are one promising area of research.

GM also offers potential solutions for the development of new food crops that would require less energy, convert solar energy more efficiently and potentially absorb carbon dioxide at a greater rate extending the possible use of coal.  But again at the opponents need to be reassured or quieted.

 

 

There is now a more extensive analysis of alternative energy sources on this website [Read here...]

 

 

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Travel

Argentina & Uruguay

 

 

In October 2011 our little group: Sonia, Craig, Wendy and Richard visited Argentina. We spent two periods of time in Buenos Aires; at the start and at the end of our trip; and we two nights at the Iguassu Falls.

Read more: Argentina & Uruguay

Fiction, Recollections & News

The Meaning of Death

 

 

 

 

 

 

'I was recently restored to life after being dead for several hours' 

The truth of this statement depends on the changing and surprisingly imprecise meaning of the word: 'dead'. 

Until the middle of last century a medical person may well have declared me dead.  I was definitely dead by the rules of the day.  I lacked most of the essential 'vital signs' of a living person and the technology that sustained me in their absence was not yet perfected. 

I was no longer breathing; I had no heartbeat; I was limp and unconscious; and I failed to respond to stimuli, like being cut open (as in a post mortem examination) and having my heart sliced into.  Until the middle of the 20th century the next course would have been to call an undertaker; say some comforting words then dispose of my corpse: perhaps at sea if I was travelling (that might be nice); or it in a box in the ground; or by feeding my low-ash coffin into a furnace then collect the dust to deposit or scatter somewhere.

But today we set little store by a pulse or breathing as arbiters of life.  No more listening for a heartbeat or holding a feather to the nose. Now we need to know about the state of the brain and central nervous system.  According to the BMA: '{death} is generally taken to mean the irreversible loss of capacity for consciousness combined with the irreversible loss of capacity to breathe'.  In other words, returning from death depends on the potential of our brain and central nervous system to recover from whatever trauma or disease assails us.

Read more: The Meaning of Death

Opinions and Philosophy

More Julian Assange

 

 

A friend forwarded me an article by Elizabeth Farrelly in the Sydney Morning Herald on April 12.  Read Here or click on the picture.



It appears that Assange's theories about petite and grand conspiracies are well founded; and illustrated by his own case.

Read more: More Julian Assange

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