Introduction and Structure - Renewable Energy: Technology, Economics and Environment - page 6

124,9

117,3

in EJ/a

143,3

21,5

Hydro power

13,2

Nuclear power

21

Coal

Natural gas

Crude oil

Fig. 1.3 Worldwide consumption of fossil primary energy carriers and hydropower accord-
ing to regions and energy carriers in the year 2005 (data according to /1-3/)

Within the past 40 years, the composition of energy carriers applied worldwide
has changed tremendously (Fig. 1.4). This applies in particular to natural gas.
While this energy carrier only had a share of roughly 17 % in the overall con-
sumption of fossil energy carriers and hydropower in 1965, it contributed with
about 24 % to cover the overall primary energy demand in 2005. In 1965, nuclear
energy had still no importance on a global scale; in the year 2005; however, it
covered roughly 6 % of the global primary energy demand and still has a strong
tendency to increase. Although coal consumption significantly increased from
62 EJ (1965) to 123 EJ (2005) its consumption diminished from 40 % in the year
1965 to scarcely 28 % in 2005, when compared to the overall consumption of fos-
sil energy carriers and hydropower. Within the same period, the consumption of
crude oil increased from about 65 EJ (1965) to approximately 161 EJ (2005). The
crude oil consumption has thus more than doubled within scarcely four decades;
however, its share in the overall primary energy consumption has more or less
remained the same.
The above indications only include power generated by hydropower and nu-
clear energy as well as energy carriers traded on the commercial world energy
markets. All other kind of renewable and un-conventional energies, such as fire-
wood and other kinds of biomass (e.g. straw, dried manure) or wind have thus not
been considered. Currently, there are only very rough estimations available re-
garding the amount and regional distribution of the energetic use of for, instance,
biomass and wind. For biomass as the most important non-commercial renewable
energy carrier, for instance, these estimations cover a very wide range and reach
from 20 to scarcely 60 EJ/a. According to these estimations, biomass contributes 5
to 15 % of the world-wide primary energy utilisation of fossil energy carriers and
hydropower to satisfy the given energy demand.