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SILICON
SILIC
CHIP
www.siliconchip.com.au
Publisher & Editor-in-Chief
Leo Simpson, B.Bus., FAICD
Production Manager
Greg Swain, B.Sc. (Hons.)
Technical Editor
John Clarke, B.E.(Elec.)
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Ross Tester
Jim Rowe, B.A., B.Sc
Mauro Grassi, B.Sc. (Hons), Ph.D
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2 Silicon Chip
Publisher’s Letter
Let’s have no more of this
carbon pollution nonsense
As we approach the end of the first decade of this
century, there are two great concerns: the global economic situation and global warming. Presently, with
a view to improving their economic situation, most
nations are not doing much about global warming,
even if they have signed up to the Kyoto Accord. Ultimately, the economic situation in most nations will
improve in a year or so and then it will be interesting
to see if there is much action on global warming.
Maybe in a year or so, the seemingly universal panic about global warming
will abate somewhat. Maybe the “science on global warming” will not seem
so “settled”. Sure, there will always be a proportion of hard-core fanatics who
think we are headed for disaster and will always call for ever more drastic
action to reduce “carbon pollution”, the prime suspect for global warming.
Well, I sincerely hope that these sentiments will eventually come to be regarded as fanatic belief rather than sensible concern based on real science.
For a start, let’s consider this highly emotive term “carbon pollution” which
is constantly being bandied about. It only takes a moment’s thought to realise
that there is no “carbon pollution” problem. It did exist 50 years ago, when
we had steam trains and diesels with smoky exhausts and coal-burning power
stations which had less than complete combustion. It used to be called soot.
But it is not a problem now, in most countries. Now I know that some people
use “carbon” as shorthand for carbon dioxide but it is sloppy thinking and
generates worry in the unthinking masses that we are spewing all this carbon
into the air. We’re not.
We are burning tremendous amounts of fossil fuels and that is putting huge
amounts of carbon dioxide into the air. Carbon dioxide is a greenhouse gas
and that is a big worry, isn’t it? Well, maybe. But all these doom merchants
who worry about carbon dioxide never say anything at all about the other
greenhouse gas which is produced when fossil fuels are burnt. What is that?
It’s called water vapour – the same stuff as in clouds. Is water vapour a problem? Definitely not.
Just in case you don’t believe me, consider the combustion of petrol which
is mainly octane, C8H18. When this is burnt, the chemical reaction is:
2C8H18 + 25O2
16CO2 + 18H2O
octane + oxygen
carbon dioxide + water
If you calculate the molecular weights of the two combustion products,
carbon dioxide and water, you will find that there is more water produced than
carbon dioxide. But greenies never mention it. Why? Because they have either
forgotten their high-school chemistry or they are completely ignorant of it.
The point is that both water vapour and carbon dioxide are normal components of the air that we breathe. They are not pollution. They are both
necessary for life to exist on the planet. If there was no carbon dioxide, plants
would not grow (more high-school chemistry – it’s called photosynthesis).
Without plants, no animals, including us, can live. It’s a simple as that. If
there is more carbon dioxide in the air, plants grow more profusely. In fact,
it is common practice to increase the carbon dioxide in greenhouses and
aquariums to make the plants grow more vigorously.
Alright, let’s say for the moment that carbon dioxide is BAD and must
continued on page 45
siliconchip.com.au
Eventually, after speaking to her husband, she gave me the go-ahead for
option two.
Replacing the electros in the power
supply was fairly routine and I also
spent some time looking for dry joints,
especially to surface-mounted components. Unfortunately, I didn’t have
a circuit diagram, so I was unable to
identify the current-sensing circuit
components and concentrate on that
area. This circuit typically involves
using a low-value resistor in the main
B+ circuit and shuts the set down if
the current goes too high.
Gods not smiling
A week later, after more extensive
tests, I reinstalled the set in the client’s
home and crossed my fingers. Unfortunately, the gods were not smiling on
me because she subsequently phoned
four days later to tell me, very coolly,
that she had stopped the cheque. She
wasn’t exactly rude but there was
plenty of “hoity-toity” snotty-nosed
attitude. There’s nothing like doing
business with someone who thinks so
highly of you!
Anyway, she told me that the set
lasted four hours before doing precisely the same thing as before. Just my
luck, I thought – I have the set for two
weeks and cannot fault it; she has it for
four hours and it fails. That’s Murphy
at his pernicious best.
I reminded her that I had emphasised that repairing the power supply
would be something of a gamble but it
didn’t cut much ice. And even if it had,
the fact was that the set was still faulty
and I was obliged to give it another go.
When I called to pick it up, her
husband was there and he was much
more relaxed and logical about things.
After some discussion, he decided
to go for option three (ie, replace the
power supply) and hang the expense.
And so that’s how this annoying
intermittent fault was finally fixed.
It’s the sort of repair that’s all part
of the “dumbing-down” trend in the
Publisher’s Letter
. . . continued from page 2
be reduced. There are two ways to do this. The first is to reduce or stop
burning fossil fuels, particularly in power stations. The second is so-called
geosequestration whereby the carbon dioxide produced in the power station
is separated from the other exhaust gases going up the stack (ie, nitrogen
and water vapour) and then pumped underground. It turns out that this
process is extraordinarily difficult.
One way to do it might be to cool the smokestack gases sufficiently (to
-78.5°C) so that the carbon dioxide solidifies (to dry ice). Or you could
cool the gases sufficiently to separate the water and then compress it sufficiently to liquefy the carbon dioxide and allow the gaseous nitrogen to
separate out. Or another scheme that has been suggested is for the power
stations to burn the coal with oxygen rather than air – so that we don’t
have the problem of removing the nitrogen.
Whatever scheme is used, geosequestration will use enormous amounts
of energy; perhaps 40% or more than is currently needed to generate electricity. Isn’t this insane? We want to get rid of carbon dioxide but we have
to mine heaps more coal and burn it to do so. On the other hand, Australians mustn’t use nuclear power (which generates very little greenhouse
gas) because that has all sorts of radioactive nasties. Never mind that a
large proportion of the electricity generated by western countries already
comes from nuclear power stations.
I should note that the term “geosequestration” now seems to have been
replaced by “carbon capture and storage (CCS) technologies” which seems
to imply that there are lots of ways of doing it. The Federal Government
proposes to spend lots of money promoting CCS – this is just more woolly
thinking. And to think that Australia might take a lead with CCS and then
sell it other countries that burn lots of coal just beggars the imagination.
Just how gullible do we think they are?
It is time that we called a halt on all this fear-mongering about global
warming and greenhouse gases. The fact is that no matter how many socalled experts forecast that the polar icecaps will melt completely (they
might) and sea levels will rise, we just don’t know if this will happen or
how rapidly it might happen. Nor do we really know if global warming
is wholly or partially caused by human activity.
By all means let us stop wasting fossil fuels, particularly oil. We need
to conserve oil for the future. And by all means let us accelerate moves to
use more solar power, nuclear power, geothermal power or whatever. But
let us not be panicked into enormously expensive moves to reduce carbon
dioxide when we don’t really know if it’s a problem or not.
Next time you see some politician or climate expert pontificating about
global warming, ask yourself, “Do they even understand basic chemistry?”
And remember, “carbon pollution” is not the problem!
Leo Simpson
Wanted: Electronics Technician
An experienced electronics technician is required to repair & overhaul
switchmode power supplies in our modern Hornsby workshop. Email
your application to:
ELECTRONICS SPECIALISTS
TO INDUSTRY AND DEFENCE
siliconchip.com.au
SWITCHMODE POWER SUPPLIES PTY LTD (ABN 54 003 958 030)
1/37 Leighton Place, Hornsby, NSW 2077.
Phone (02) 9476 0300
email: martin.griffith<at>switchmode.com.au
webpage: www.switchmode.com.au
June 2009 45
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