|
|
Oil Reserves:
A Public Radio Commentary
by Bill Hammack
Listen using RealAudio
Recently, I caught a shocking headline: The Shell Oil Company
"lost" one-fifth of their oil reserves overnight, about four
billion barrels. That is, they reduced their estimate of the
amount of oil in the ground. Alarmed by this news I decided to
find out exactly how long our oil will last.
As an engineer I prepared to decipher complex graphs, but what I
really needed was a linguist, a fortune teller, and a philosopher
of human nature.
Figuring out how much longer we'll have oil appears simple: Find
out how fast we use oil, find out the barrels of oil under the
ground, then combine the two. This method yields an answer of
twenty to forty years of oil reserves. But, of course, it isn't
that simple.
In the 1920s observers calculated that by 1930 we'd run out of
oil. They overestimated the rate we'd use oil, and they didn't
know about oil fields in the Middle East, South American, Africa,
Siberia, Alaska, or the North Sea.
So, can we just take the current rate of consumption and use the
reserves reported by the oil companies to calculate how long the
oil will last? - that's how I got the twenty to forty year
figure. At this point a linguist would come in handy. The oil
companies report "proven reserves," defined as "those quantities
of oil which are known to be in place and are economically
recoverable with present technologies." Note those phrases
"economically recoverable" and with "present technology." Right
now we recover oil from porous underground rock. A significant
fraction of the oil sticks to the rocks; we recover, at best,
about eighty percent, usually a lot less than that. So, when we
estimate how much oil reserves should we include this oil?
Perhaps a way will be found to cheaply recover this left-over
oil? The same question applies to other sources: The Canadian
province of Alberta contains the Athabasca Tar Sands, which have
an oil content close to current proven reserves. And in America,
Colorado's oil shale also contains vast oil reserves. Now
extracting the oil isn't easy, the harsh climate in Alberta
freezes the tar solid, and it takes 30 tons of shale to make 1
ton of oil.
So, the answer to when the oil really runs out comes down to a
question of faith about the limits of human inventiveness: Will
our technological wizards develop ways to cheaply tap other
sources; or, have we reached a technological limit? In the past,
bets against human ingenuity usually lost, the prophets of dome
have nearly always been wrong.
Perhaps, though, in this case, we should follow the old Russian
proverb: Pray to God, but keep rowing toward shore. In other
words, hope that those engineering wizards will come through, but
with the current oil reserves we should conserve, conserve,
conserve.
Copyright 2004 William S. Hammack Enterprises
|
|
