Environmental Engineering Reference
In-Depth Information
Crude oil production (million metric tonnes)
4000
3500
3000
2500
2000
1500
1000
500
0
1860
1880
1900
1920
1940
1960
1980
2000
Source:
BP, 2003; IEA, 2003a
Figure 1.4
Evolution of Annual Crude Oil Production
Figure 1.4 shows the annual oil production, illustrating the enormous
increase in world energy consumption. One million metric tonnes of crude oil
have an energy content of about 42 PJ or 42
•
10
15
J. Production rates
increased exponentially after World War II. Two oil crises, in 1973 and 1978,
slowed down this development, holding back the development of world
economic growth and the energy demand until 1982.
Table 1.4 shows the
world primary energy consumption
of different energy
sources over much of the last century. The estimation of primary energy
equivalents for nuclear electricity and hydro-electricity is inconsistent; the
majority of the newer statistics multiply the electricity output of nuclear power
stations by 2.6 or 3 to obtain the primary energy demand. This considers the
conversion efficiency of thermal power plants to be 38 per cent, or 33 per cent.
The efficiency of hydro-electric power plants is much higher and can even
reach values of 90 per cent or more. Since the real efficiency of hydro-electric
power plants is difficult to estimate during operation, some statistics define
the output as primary electricity and assume an efficiency of 100 per cent.
Thus, hydro-electric power plants need much less primary energy than nuclear
power plants to produce the same amount of electricity. However, statistics
comparing the world primary energy supply of nuclear power plants
(multiplied by 2.6 or 3) with that of hydro-electric power plants (multiplied by
1) give the impression that the hydro-electricity share is much less than that of
nuclear electricity, although the world electricity supply of both is similar.
Table 1.4 does not contain other renewable energy sources such as biomass
(e.g. firewood and vegetable waste), wind energy, solar energy and geothermal
energy. The section in this chapter (p19) on global use of renewable energy
resources will describe the contribution of renewable energy.
