Environmental Engineering Reference
In-Depth Information
renewables. Only three centuries ago, renewable energy sources provided
virtually the entire global energy supply and many studies show that this might
be achieved again in the future. However, other renewable energy sources such
as solar power and wind power will be crucial in the future. This section shows
the installed capacity and the growth rates of recent years for different
renewable energy sources, starting with the electricity supply where renewables
provided about 18 per cent of the global demand in 2001.
Use of renewable energy sources for electricity generation
The amount of
wind power
installed worldwide has grown rapidly since the
mid-1990s. Between 1994 and 2002 the installed capacity grew nearly ten
times. However, very few countries encourage this development. About 77 per
cent of the global capacity in 2002 was installed in five countries. Table 1.12
shows the development of the generating capacity of wind power in these
countries over recent years. Only in Denmark has wind power reached a
market share of more than 10 per cent of the electricity supply. However, the
potential in other countries is enormous. For instance, only 570 MW was
installed in the UK in 2002, but the potential for wind power exceeds 1000
GW. In 2002 wind-generated electricity worldwide was about 50 TWh, which
is 0.33 per cent of total global electricity generation. However, if the growth
rates of wind power are maintained over the next two decades, wind power
can become the most important renewable energy source for electricity
generation, with a market share of well above 10 per cent.
The installed capacity of
photovoltaic systems
is much smaller than wind
power. However, growth rates are of the same order of magnitude as wind
power and the cost of photovoltaics is decreasing much faster (see Chapter 6).
In 2002 about 1.6 TWh was generated by photovoltaic systems, which is
equal to 0.01 per cent of global electricity generation. Table 1.13 shows the
countries with the highest numbers of installed photovoltaic systems and their
generating capacity between 1992 and 2002. In 2003, the growth in Japan
was significantly higher than elsewhere with the result that nearly one third of
global capacity is installed in Japan alone. The second largest market,
Germany, contributes roughly half as much. However, the installed global
capacity is about one decade behind that of wind power.
Table 1.12
Worldwide Total Installed Wind Generator Power in GW
Year
1994
1995
1996
1997
1998
1999
2000
2001
2002
Germany
0.60
1.09
1.55
2.08
2.88
4.44
6.11
8.73
12.00
Spain
0.08
0.13
0.25
0.51
0.88
1.81
2.84
3.55
5.04
US
1.54
1.59
1.60
1.61
2.14
2.45
2.61
4.23
4.67
Denmark
0.54
0.64
0.84
1.11
1.42
1.74
2.34
2.46
2.88
India
0.20
0.58
0.82
0.94
0.99
1.04
1.22
1.46
1.70
Others
0.55
0.75
1.05
1.38
1.85
2.46
3.34
4.48
5.77
Total
3.51
4.78
6.10
7.64
10.15
13.94
18.46
24.92
32.07
