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“as-mined” ore, which would be slightly lower in grade. The availability of reliable
data regarding iron grades and production trends dates back to 1907, although there
are single figures for some years as far back as 1850. Ore grades unfortunately are
missing for the following time periods or individual years: 1930 - 1934; 1936 - 1940;
1946 - 1951; 1966 and 1994. These absences are represented by a horizontal straight
line in Fig. 13.15 assuming the value of the last available record.
The Hubbert Peak Model satisfactorily applies to Australian iron reserves, as
can be seen in Fig. 13.16. The theoretical peak year is set to be reached in 2030,
considering that the economic demonstrated reserves are R
1907
= 15:8 Gtoe. The
regression factor is also very acceptable: RF = 0:94.
13.3.8 Coal
Australian coal was first discovered in 1791 in New South Wales with the first
coal mining settlement established there in 1801 (AusIMM, 1993). Since then, coal
mining has increased dramatically and now occurs in every state. Around 75% of
the coal extracted is exported, mostly to East Asia. Consequently, the country has
become the fourth largest coal producer in the world. Coal also provides for around
85% of the national electricity production with its relative abundance, reliability
and low cost having ensured that it remains the most commonly used fuel source
for Australian electricity generation (ISR, 2001).
The main types of coal extracted are bituminous and to a lesser extent, lignite.
Small amounts of subbituminous and traces of semi-anthracite are also produced.
250,000
B, ktoe
200,000
150,000
100,000
50,000
Subbituminous
Lignite
Bituminous
0
Year
Semi-anthracite
Bituminous
Subbituminous
Lignite
Fig. 13.17 The exergy loss of Australian coal reserves
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