Environmental Engineering Reference
In-Depth Information
power then were animals, wood, and waterwheels. Energy
intensity declined at an average rate of about
% per year,
right through the transition to commercial fossil fuels
(coal
first and then oil) in the late nineteenth century.
There is one notable exception, the period from about
. This was the time of the OPEC oil
embargo, and the Iranian revolution. The resulting huge
increase in oil prices drove a large-scale and successful
effort to improve the ef
to
ciency of energy use throughout
the United States and the world economies. In the mid-
s, oil prices dropped and the economies went back to
their old ways. The high prices of fossil fuels today are
once again driving a move toward more ef
cient use of
energy, which is good for the economy and for reducing
greenhouse gas emissions. In the industrialized world,
energy intensity is now declining at a rate of about
.
%
per year. China
-year plan had a goal of
reducing energy intensity by
'
s previous
% per year between
. The government says they succeeded,
although some question the accuracy of the analysis.
However, the Chinese economy has been growing so fast
that their emissions have risen by about
and
% per year over
the same period.
To predict future energy demand, I will use data from a
study by the International Institute of Applied Systems
Analysis (IIASA) and World Energy Council (WEC) [
].
The income and energy-intensity data are from
and
earlier. Although these are not the most recent data, their
report is available on the Web and the viewer can inter-
actively see what happens as assumptions are changed.
The projections are close enough to more recent ones
that trends and broad conclusions are unaffected.
