Environmental Engineering Reference
In-Depth Information
Coal, coal everywhere
Certainly there will not be any shortage of coal in the near future. It
is the most abundant of the fossil fuels. Estimates of total potential
resources some of them uncommercial and of the narrow category of
proven reserves (considered commercial) have gone up in recent years.
According to figures established in 2009 by the German Federal Institute
for Geosciences and Natural Resources, economically recoverable reserves
of hard coal are 729 billion tonnes and - on top of that - total potential
resources are around 16,000 billion tonnes.
Likewise, reserves of brown coal
or
lignite amount to 269 billion tonnes
and, in addition, total lignite resources amount to over 4,000 billion
tonnes. Reserves and resources on this scale would last the world at least
150 years at the current (2009) rate of production, even assuming China
maintains its present enormous output. In fact, burning even a small frac-
tion more of these reserves will put the climate in severe danger. As the
IEA says in its 2009
World Energy Outlook
, “limits to the use of coal come
not from any lack of reserves, but from logistical factors and - above all -
from the environmental effects of its use”.
Why is coal staging a comeback? Part of the answer lies in problems
with alternatives: in recent decades nuclear operations have seemed less
safe and gas supply less reliable. But the fundamental reason why coal is
regaining a share in the world energy mix is because it is cheaper to pro-
duce as a fuel than oil and gas. It is also as easily transportable as oil and
more so than gas, and is cheaper to use as a fuel than uranium, the fuel
source of nuclear power plants, because it does not need a complicated
reactor.
Today's coal mining is increasingly sophisticated - with longwall cut-
ting machines for mining underground seams and huge cranes for strip
mining, as well as some legacy Dickensian shovel-and-pick operations.
The capital costs of digging coal remain lower than the expense of extract-
ing oil and gas. World coal prices have kept pace with trends in oil and gas
prices sometimes because of contractual linkages and sometimes because
some power plants can switch back and forth between coal and gas. But
the peaks in coal prices have had less to do with capital costs and supply
issues and more to do with coal's popularity.
Coal also remains in use because of issues of national (and interna-
tional) energy security. The geographical concentration of coal is greater
than for oil or gas. The countries that are the top ten coal reserve-holders
