Environmental Engineering Reference
In-Depth Information
3.2 Energy Consumption by Sector
Energy supply involves the delivery of fuels, electricity, or heat from the point of
production to that of consumption. It encompasses the extraction, transformation,
generation, transmission, distribution, and storage of commodities (see Figure 3.2 ). Far
more energy is produced than consumed because losses occur in conversion and delivery
(see Figure 3.3 ) . 2 Total world energy production is roughly 530 exajoules (EJ) - one
million trillion joules (10 18 joules; see Table 3.7 ) - while global final consumption after
losses is 350 exajoules (BP 2011 ; IEA 2012a ).
Figure 3.2. The global system for energy production and consumption. Most of the
sources, processes, and methods of consumption involve greenhouse gas (GHG) emission.
Biomass also involves CO 2 removal. Source: Arvizu et al. ( 2011 b ).
Figure 3.3. Global energy flux describing the path from energy production to
consumption. The conversion and consumption pathways show that most coal goes to
power plants, natural gas is equally divided between direct consumption and the
residential sector, while most oil is consumed in transportation. This diagram also
illustrates the global loss of energy through conversion, which accounts for more than 30
per cent of primary production. Source: IEA website (modified).
Table 3.6.
Energy (in joules) released by some phenomena, devices, and power
plants
J
kWh
1
0.00000028
Search WWH ::




Custom Search