Figure 2.6: (a) Development of the installed capacity (in GW) of several non-fossil electricity generation technologies
since 1980. (b) The same graph corrected by the capacity factor C F and extrapolated until 2020.
Of course, we have to justify why solar electricity can grow much faster than the
other technologies shown in Figure 2.6. First, solar radiation is available everywhere on
Earth and it is available in great abundance. The amount of solar energy incident on Earth
is about 10,000 times larger than the total energy
2
consumption of mankind. As
hydroelectricity is powered by water that is evaporated by the Sun and falls on the ground
as rain, it is a secondary form of solar energy. Also, wind arises from temperature and
pressure differences in the atmosphere and hence is a secondary form of solar energy. As a
consequence, solar energy is by far the largest available form of renewable energy.
Secondly, hydro- and nuclear electricity are centralized electricity generation
technologies. For hydropower plants, big dams are needed. Also nuclear power plants
have large power rates of about 1 GW. Building new hydro- and nuclear power plants
requires large public or private investments. While solar electricity can be generated in
large PV parks or solarthermal power plants (see Chapter 22), it also has a unique
advantage: PV systems can be installed decentralized on every roof. Electricity consumers
can generate at least a part of their required electricity on their own homes, which makes
them partially independent of the electricity market. In addition, the cost price of PV
since 1980. (b) The same graph corrected by the capacity factor C F and extrapolated until 2020.
Of course, we have to justify why solar electricity can grow much faster than the
other technologies shown in Figure 2.6. First, solar radiation is available everywhere on
Earth and it is available in great abundance. The amount of solar energy incident on Earth
is about 10,000 times larger than the total energy
2
consumption of mankind. As
hydroelectricity is powered by water that is evaporated by the Sun and falls on the ground
as rain, it is a secondary form of solar energy. Also, wind arises from temperature and
pressure differences in the atmosphere and hence is a secondary form of solar energy. As a
consequence, solar energy is by far the largest available form of renewable energy.
Secondly, hydro- and nuclear electricity are centralized electricity generation
technologies. For hydropower plants, big dams are needed. Also nuclear power plants
have large power rates of about 1 GW. Building new hydro- and nuclear power plants
requires large public or private investments. While solar electricity can be generated in
large PV parks or solarthermal power plants (see Chapter 22), it also has a unique
advantage: PV systems can be installed decentralized on every roof. Electricity consumers
can generate at least a part of their required electricity on their own homes, which makes
them partially independent of the electricity market. In addition, the cost price of PV