Coal Usage to Generate Electricity

Coal Usage - Sobering Facts

 We are the Future Eaters.

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This is a page about something that should be of passionate concern to everyone.  See updates further down the page.

Also check out the madness of humans on the oil usage page.

Think about this - What is the ONLY important job in the world?  
Answer: Creating the next generation.  If we don't do that then all the cities, ports, technology, art, music etc etc are meaningless.

Next thought - What are we leaving these coming generations?  
Answer:  Bugger all!

Makes you proud doesn't it?

What can we do about it?  Try to convince our leaders to be leaders.  Just for once.  Just for once say 'Oz is a developed country, we owe it to the developing nations to show leadership by solving these issues.  Or at least trying'.

Why aren't our farmers being encouraged / supported to farm what they have lots of, in many cases too much of - sunlight.  We should have big solar farms producing either electricity for the grid, or better still hydrogen or similar.

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Coal usage in the state of NSW, Australia

(see below for usage in the USA)

Q. How much coal is used to produce electricity in NSW?
A. We measure the rate of electricity production in Megawatt Hours, or sometimes its expressed as Gigawatt Hours.  1 Gigawatt = 1000 Megawatts = 1,000,000 Kilowatts.  So to get to the answer:  To produce 1000 Megawatts for 1 Hour (ie 1000 Mw/Hr's) it takes 500 tonnes of coal.

Q. On average, how much electricity is used by the state of N.S.W, Australia? (population 6.7 million, 2001)?
A. about 8,000 megawatt hours (8000 MW/Hr)

Q. Why do you say 'on average'?
A. The amount of electricity getting used varies all the time.  It goes up in the morning around 9 am, then reduces, then goes up again around 6 pm at night.  It also varies with summer / winter and the weather.  The 'peak' demand in summer and winter is > 10,000 Mw/Hrs.

Q. How much coal was burnt to produce the 2001 electricity?
A.  For the year - 35 million tonnes

Q. How much coal does a typical everyday 18-22 wheel highway semi-trailer hold?
A. 25 tonnes


Q. How often would those semi-trailers loads of coal get burnt?
A. To generate at 8000 Mw/Hrs it takes 1 semi-trailer of coal every 23 seconds.

Q. How much carbon dioxide is produced from that coal?
A. Burning 35 million tonnes of coal we make about 94 million tonnes of CO2.
How is it so? The following comes from good old Foundation A theory:
Application of Atomic Weights to Chemical Reaction. Knowledge of atomic weights enables the relative weights of each of the elements and compounds involved in a chemical reaction to be determined. For example, the weight of oxygen necessary for the complete combustion of a certain weight of carbon can be readily determined as follows:
C + O2 = CO2, Atomic weight C=12; Atomic weight O2=32; Molecular weight CO2=44.
By substituting the above atomic and molecular weights by weights expressed in kilos we can say: “12 kg of carbon will combine with 32 kg of oxygen to produce 44 kg of carbon dioxide”.
1 kg of carbon will combine with 32/12 = 2-2/3 kg of oxygen to produce 44/12=3-2/3 kg of carbon dioxide.
Now, we know that good coal (not the Victorian rubbish) has between 60% and 73% Carbon (ultimate analysis – includes volatiles), so one tonne of top coal produces: 1 tonne x 0.73 x 3.667 = 2.676 tonnes of CO2 (if there’s no unburnt carbon, and neglecting CO, SOX, etc.)
Thus at 35 million tonnes per year of coal, we make about 94 million tonnes of CO2!! For coals with lower carbon content, since the CV is almost linear with carbon content, the result is much the same!
We should all be ashamed of ourselves!
(The above answer and detail with many thanks to a mate from the China Trip - Terry Plunkett)

Q. How much coal does Australia export?
A. About 80 million tonnes a year, just from Newcastle NSW.  Other major exports are from Queensland.

Q. If we had to use 25 ton semi-trailers to deliver that coal to Newcastle, how many would it take?
A. Heaps.  They would be unloading at the rate of 1 every 10 seconds, 24 hours of the day, 365 days of the year.

Q. So how much coal does an average 2+2 Oz family use to create their years worth of electricity?
A. The coal consumption per man, woman and child is 35,000,0000 tonnes per year, divided by 6.1 million people, approx 6 tonnes of coal per year for each person. Or that could be equated to a semi trailer of coal per household for a 4 person family on average. (Many thanks to an old mate Blue Gould for this observation)


   UPDATE - Coal Usage for Electricity in the USA

Q. How much coal does the USA use to generate electricity?
A. Here is the US government report for coal consumption in 2008
In summary, coal provided 48.2% of the USA's electricity (ie 1,986 million megawatt hours).  To do this it consumed 1,042,335,000 tons of coal.
(http://www.eia.doe.gov/cneaf/electricity/epa/epaxlfile3_1.pdf gives you coal consumption figures for each of the years 1997 to 2008).

Q. So whats that in terms I can comprehend?
A. Yep, those big numbers are overwhelming, so lets get it down to something in everyday life we can comprehend - normal highway 25 ton semi-trailers.  To supply coal at that 2008 rate it would have taken 4,760 semitrailers / hour, or one 25 ton semitrailer every 0.8 of a second. 

Q. So how fast would the semi-trailers be going?
Assuming each semi is 20 meters long, and they travel nose to tail, to supply that coal rate they would travel at 90 kph (56 mph) in a continuous convoy and dumping as they moved.

I would like to see an explanation of how we can sustain this.

PS The USA produced 2,477 million metric tons of CO2 in 2008 from burning this coal.


Another Update - Why We Need To Change

Al Gore spoke about Inconvenient Truths and I agree with him.  However I think he could have gone further with the list of Inconvenient Truths about energy in general and reinforce why we need to change. 
Here's my quick list of 'Inconvenient Truths':

  1. The worlds resources are finite
  2. The worlds population is expanding
  3. Our use of those resources is expanding
  4. Our major energy source has always been carbon based - wood, oil, coal
  5. Those three energy sources all originate from solar energy.
  6. It has taken thousands of years for oil and coal to form and make a useful (to us) store of that former solar energy.
  7. We have consumed a large quantity of that stored energy in about two hundred years (ie the Industrial age).  And released their byproducts.
  8. Our rate of release is increasing
  9. There is (arguably) a 90% chance that our release of carbon so far is seriously starting to affect the atmosphere and climate that is essential for all life as we know it.
  10. There is limited scope in the world for further development of hydro power.  Dams require sterilizing arable valley land.  Australia in particular is affected by lack of height and overall low rainfall.
  11. There is nowhere on the earth that man has not been.  The old days of 'Go west and start again' are over.  And we do not have the technology to 'Go to the next planet and start again'
  12. Nuclear energy is a possibility however it is expensive, long lead times to build (let alone the politics involved), requires long time storage for its remains and can be catastrophic when things go wrong - just look at current events in Japan.  (And I would sure as hell start running if some of the existing electricity generators in Australia were put in charge of one.)
  13. Large scale solar derived energy (wind, solar, tidal etc) require largish areas of land.
  14. Solar derived energy is technically simple and really not that expensive.  Its just that fossil fuel energy (ie stored solar energy) is so much cheaper.
  15. To change the existing way of energy supply that we have all got used to and love will cost time and money.

So to some questions for any reader:

Q1. Do we accept that naturally formed carbon based fuels are finite?  (The answer has to be YES.)

Q2. At what point do we say we have to change to a different, hopefully more sustainable, energy source?  Do we just 'party on' and wait until crunch time?  Or do we start the change much earlier (now) while the world still has ample carbon fuels to effect that change.

Q3. Who should start the change?  Do we try to get everyone to start the change at once?  Or do some nations need to start leading by example? Or should we just adopt the much maligned ostrich approach and bury our heads?

Q4. If we decide on some nations leading by example then which nations are best positioned to do so?  Those who have most benefited from the consumption of carbon fuels, who are economically well off, technologically advanced and politically stable?  Or should it be those nations who are still developing?

Q5. If we decide that all nations need to move as one on the problem and many refuse, then do we just all sit back and nobody moves?

Q6. If you agree that solar is too dear, or the opposite that carbon based fuel is too cheap, then how do we make the playing field at least level?

Notice that none of the questions mentions climatechange or global warming.

I look foward to comments.


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