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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

Hong Kong and Shenzhen China

 

 

 

 

 

Following our Japan trip in May 2017 we all returned to Hong Kong, after which Craig and Sonia headed home and Wendy and I headed to Shenzhen in China. 

I have mentioned both these locations as a result of previous travels.  They form what is effectively a single conurbation divided by the Hong Kong/Mainland border and this line also divides the population economically and in terms of population density.

These days there is a great deal of two way traffic between the two.  It's very easy if one has the appropriate passes; and just a little less so for foreign tourists like us.  Australians don't need a visa to Hong Kong but do need one to go into China unless flying through and stopping at certain locations for less than 72 hours.  Getting a visa requires a visit to the Chinese consulate at home or sitting around in a reception room on the Hong Kong side of the border, for about an hour in a ticket-queue, waiting for a (less expensive) temporary visa to be issued.

With documents in hand it's no more difficult than walking from one metro platform to the next, a five minute walk, interrupted in this case by queues at the immigration desks.  Both metros are world class and very similar, with the metro on the Chinese side a little more modern. It's also considerably less expensive. From here you can also take a very fast train to Guangzhou (see our recent visit there on this website) and from there to other major cities in China. 

Read more: Hong Kong and Shenzhen China

Fiction, Recollections & News

The First Man on the Moon

 

 

 

 

At 12.56 pm on 21 July 1969 Australian Eastern Standard Time (AEST) Neil Armstrong became the first man to step down onto the Moon.  I was at work that day but it was lunchtime.  Workplaces did not generally run to television sets and I initially saw it in 'real time' in a shop window in the city.  

Later that evening I would watch a full replay at my parents' home.  They had a 'big' 26" TV - black and white of course.  I had a new job in Sydney having just abandoned Canberra to get married later that year.  My future in-laws, being of a more academic bent, did not have TV that was still regarded by many as mindless.

Given the early failures, and a few deaths, the decision to televise the event in 'real time' to the international public was taking a risk.  But the whole space program was controversial in the US and sceptics needed to be persuaded.

Read more: The First Man on the Moon

Opinions and Philosophy

The Chemistry of Life

 

 

What everyone should know

Most of us already know that an atom is the smallest division of matter that can take part in a chemical reaction; that a molecule is a structure of two or more atoms; and that life on Earth is based on organic molecules: defined as those molecules that contain carbon, often in combination with hydrogen, oxygen and nitrogen as well as other elements like sodium, calcium, phosphorous and iron.  

Organic molecules can be very large indeed and come in all shapes and sizes. Like pieces in a jigsaw puzzle molecular shape is often important to an organic molecule's ability to bond to another to form elaborate and sometimes unique molecular structures.

All living things on Earth are comprised of cells and all cells are comprised of numerous molecular structures.

Read more: The Chemistry of Life

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